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NHS South Birmingham Primary Care Trust

Modelling the potential impact of Enhanced Public Health Programmes on population level risk reduction in cardiovascular disease (CVD) and subsequent acute hospital admission rates over a 5 year period

Summary Report

Professor Malcolm David Whitfield 2009


Contents 1. Executive summary ........................................................................................................ 4 a. Background........................................................................................................... 4 b. Summary of the results......................................................................................... 5 Risk reduction targets............................................................................................ 5 Populations.............................................................................................................. 5 Results – 5% - 6% reduction in mean risk levels - (Scenario 1)....................... 6 Estimated acute events avoided: scenario 1 ........................................................... 6 Estimated deaths avoided: scenario 1 ..................................................................... 6 Estimated revenue costs avoided: scenario 1 ......................................................... 6 Results – 3% - 4% reduction in mean risk levels – (Scenario 2)...................... 7 Estimated acute events avoided: scenario 2 ........................................................... 7 Estimated deaths avoided: scenario 2 ..................................................................... 7 Estimated revenue costs avoided: scenario 2 ......................................................... 7 c. Conclusion............................................................................................................. 8 d. Limitations ............................................................................................................. 8 2. Background..................................................................................................................... 9 a. The strategic intention .......................................................................................... 9 b. Coronary Heart Disease in NHS South Birmingham .......................................... 9 c. Shifting the focus: health and well being v diagnosis and treatment ................ 10 d. NHS South Birmingham Enhanced Public Health Programmes ...................... 12 3. Study aims and objectives............................................................................................ 13 a. Aim of the study .................................................................................................. 13 b. Study objectives.................................................................................................. 13 4. Study design / methodology......................................................................................... 14 5. Validation ...................................................................................................................... 15 a. Validation against 5 South Yorkshire PCT (2003 data)..................................... 15 b. Validation against the Birmingham PCT’s (2008 data) ..................................... 16 6. Results (PCT level)....................................................................................................... 18 a. Estimated acute events avoided (PCT level)..................................................... 18 b. Estimated deaths avoided (PCT level)............................................................... 19 c. Estimated revenue consequences (PCT level) ................................................. 20 7. Results (1st Quintile level)............................................................................................. 22 a. Estimated acute events avoided (Quintile level 1)............................................. 22 b. Estimated deaths avoided (Quintile level 1) ...................................................... 23 c. Estimated revenue consequences (Quintile level 1) ......................................... 23 8. Results (1st and 2nd Quintile level) ................................................................................ 25 a. Estimated acute events avoided (Quintile level 1&2)........................................ 25 b. Estimated deaths avoided (Quintile level 1&2).................................................. 26 c. Estimated revenue consequences (Quintile level 1&2)..................................... 26 9. Conclusion .................................................................................................................... 27

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10. Risk level reduction .................................................................................................... 28 a. Smoking cessation – studies.............................................................................. 28 b. Smoking cessation – guidance .......................................................................... 29 c. Obesity – studies................................................................................................. 29 d. Obesity – guidance............................................................................................. 29 e. Cholesterol – studies .......................................................................................... 30 f. Cholesterol – guidance........................................................................................ 30 g. Systolic blood pressure – studies....................................................................... 30 h. Systolic blood pressure – guidance ................................................................... 31 i. CHD – diet – studies ............................................................................................ 32 j. CHD – exercise – studies .................................................................................... 32 k. CHD – exercise – guidance................................................................................ 33

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1. Executive summary a. Background Current health policy at the level of the World Health Organisation, The European Union and the UK government is encouraging the payers in health systems to concentrate their investment on health and wellbeing rather than diagnosis and treatment through the reduction of modifiable population level risk factors. This principle underpins current policy in England and is the key concept underpinning the “World Class Commissioning” agenda. The question arises, however: “How can a resource-limited commissioner in a health system be confident that investment in public health will lead to a reduction in the demand for healthcare further downstream?” Also: “What might the timescale be for such a return on investment?” This study explores the possible clinical and economic impact of investment in a public health based, population-level health risk reduction program within NHS South Birmingham PCT, with a particular emphasis on the potential return on investment in terms of acute episodes of ill health avoided, premature deaths avoided, acute hospital admissions avoided and subsequent revenue costs avoided. The study uses a combination of evidence from the literature to construct a mathematical model which estimates the number of heart attacks, strokes, heart failure events and kidney failure events for a given population. The calculation is based upon the number, age and sex of the people in the population and the mean levels of risk factors including systolic blood pressure, mean body mass index, cholesterol levels, smoking status and HBA1c levels. The predictive accuracy of the estimation is then tested by comparing the predicted number of acute events with the actual number of acute events by HRG code. The estimates are based upon modified risk equations from the US Framingham study, with adjustments for the higher risk of diabetes patients and the level of cardiovascular risk of the populations. The result of the study is to estimate the order of impact that a program aimed at reducing population level body mass index, blood pressure levels, cholesterol levels and smoking rates could achieve. The results are expressed in terms of acute hospital admissions avoided, premature deaths avoided and potential revenue cost savings. Clearly these risk factors are determined by the lifestyle of individuals and groups within a population. The report includes a summary of the main research literature relating to health improvement interventions and makes some observations on how current public health interventions could be restructured rather than added to in order to increase impact.

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b. Summary of the results The model estimates the potential impact of different levels of risk reduction in the adult population on future acute events, deaths and costs. Risk reduction targets For the purpose of this report the model has assumed two potential levels of risk reduction as outlined in fig 1: Fig 1 Risk factor

Scenario 1: Optimistic target from the literature -5% reduction -0% reduction -13% reduction -6% reduction +6% increase -5% reduction

Obesity (indicated by mean BMI) HBA1c level in Type 2 diabetics (mean) Smoking rates Mean total cholesterol (mmol/l) Mean HDL cholesterol (mmol/l) Mean systolic blood pressure

Scenario 2: Less Ambitious target from the literature -2% reduction -0% reduction -10% reduction -4% reduction +4% increase -3% reduction

These levels of risk reduction have been achieved in studies around the world. The assumption in the model is that the risk reduction would be achieved incrementally over a five year period. Populations For the purpose of this report, the model has been run for three populations: 1. All adults aged between 15 and 75+ registered with NHS South Birmingham PCT = Population: (male = 141,708) (female = 144,543) (total = 286,251) 2. All adults aged between 15 and 75+ living in Quintile 1 & 2 (highest deprivation) = Population: (male = 31,685) (female = 31,885) (total = 63,570) 3. All adults aged between 15 and 75+ living in Quintile 1 (highest deprivation) = Population: (male = 5,903) (female = 5,672) (total = 11,575) The results tables show the impact of reducing mean population level risk at the levels shown in scenario 1 and scenario 2 on each of the three populations above. Clearly an initiative which targeted the highest risk population (Quintile 1 population 11,575) would have the triple advantage of minimising financial risk, achieving the greatest gain and closing the in-equalities gap with other less deprived areas.

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Results – 5% - 6% reduction in mean risk levels - (Scenario 1) Estimated acute events avoided: scenario 1 Fig 2 shows the estimated number of acute hospital admission events avoided with a 5% - 6% reduction in mean risk factors in the three populations identified above: Fig 2 Population

PCT Population (286,251) Quintile 1&2 Population (63,570) Quintile 1 Population (11,575)

Estimate annual events (current risk levels)

Estimate annual events (improved risk levels)

Estimated annual events avoided after five years

Estimated events avoided over the 5 year period

5,478

3,892

1,585

4,756

2,805

2,211

594

1,781

2,178

1,808

369

1,108

Estimated deaths avoided: scenario 1 Fig 3 shows the estimated number of deaths avoided with a 5% - 6% reduction in risk factors (Scenario 1) Fig 3 Population

PCT Population (286,251) Quintile 1&2 Population (63,570) Quintile 1 Population (11,575)

Estimate annual deaths (current risk levels) 1,718

Estimate annual deaths (improved risk levels) 1,332

Estimated annual deaths avoided 385

Estimated deaths avoided over the 5 year period 1,155

356

276

80

240

60

47

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Estimated revenue costs avoided: scenario 1 Fig 4 shows the estimated acute hospital admission costs avoided with a 5% - 6% reduction in risk factors (Scenario 1) Fig 4 Population

PCT Population (286,251) Quintile 1&2 Population (63,570) Quintile 1 Population (11,575)

Estimate annual costs (current risk levels) £15,875,679

Estimate annual costs (improved risk levels) £11,606,139

Estimated annual costs avoided £4,269,540

Estimated costs avoided over the 5 year period £12,808,620

£7,542,951

£5,979,277

£1,563,673

£4,691,020

£5,599,753

£4,651,808

£947,945

£2,843,835

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Results – 3% - 4% reduction in mean risk levels – (Scenario 2) Estimated acute events avoided: scenario 2 Fig 5 shows the estimated number of acute hospital admission events avoided with a 3% - 4% reduction in risk factors (Scenario 2) Fig 5 Population

PCT Population (286,251) Quintile 1&2 Population (63,570) Quintile 1 Population (11,575)

Estimate annual events (current risk levels) 5,478

Estimate annual events (improved risk levels) 4,437

Estimated annual events avoided 1,041

Estimated events avoided over the 5 year period 3,122

2,805

2,424

381

1,142

2,178

1,946

231

694

Estimated deaths avoided: scenario 2 Fig 6 shows the estimated number of deaths avoided with a 3% - 4% reduction in risk factors (Scenario 2) Fig 6 Population

PCT Population (286,251) Quintile 1&2 Population (63,570) Quintile 1 Population (11,575)

Estimate annual deaths (current risk levels) 1,718

Estimate annual deaths (improved risk levels) 1,461

Estimated annual deaths avoided 256

Estimated deaths avoided over the 5 year period 769

356

303

53

160

60

51

9

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Estimated revenue costs avoided: scenario 2 Fig 7 shows the estimated acute hospital admission costs avoided with a 3% - 4% reduction in risk factors (Scenario 2) Fig 7 Population

PCT Population (286,251) Quintile 1&2 Population (63,570) Quintile 1 Population (11,575)

Estimate annual costs (current risk levels)

Estimate annual costs (improved risk levels)

£15,875679

£12,951,907

£2,923,772

Estimated costs avoided over the 5 year period £8,771,316

£7,542,951

£6,513,780

£1,029,171

£3,087,513

£5,599,753

£5,001,585

£598,168

£1,794,504

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Estimated annual costs avoided


c. Conclusion If the PCT can reduce mean risk factors across the total population by an average of 5% - 6%, over five years, this could reduce annual admissions by up to 1,585 per year, prevent up to 385 premature deaths per year and save up to £4.2 million per year on acute hospital costs alone. Non-recurrent cumulative savings over the five year period could be as high as £12.8 million. If the average risk factors across the total population were reduced by a more modest 3% - 4% over five years this could still reduce annual admissions by up to 1,041 per year, prevent up to 256 premature deaths per year and save up to £2.9 million per year on acute hospital costs alone. Non-recurrent cumulative savings over the five year period could be as high as £8.7 million. Clearly reducing mean risk factors across the population of a City the size of NHS South Birmingham would be a major feat. If the emphasis was in the most deprived areas this would have the duel effect of maximising impact and reducing health inequalities. Even a pilot aimed at the top two quintiles of deprivation, if successful, could reduce acute events by between 381 and 594 per year, reduce premature deaths by between 53 and 80 per year lead to potential annual savings on hospital admission of between £1.0 and £1.6 million

d. Limitations Clearly the model is predicting huge reductions in acute events and costs with minimal reductions in mean relative risk. This is in line with the literature. The model uses the best evidence available to quantify, in a systematic way, the potential impact of population level risk reduction on future acute events. The World Health Organisation (WHO) calculates that over a third of the burden of disease in the world can be linked to these reducible risk factors. It is therefore assumed that a reduction in the risk factors will lead to a reduction in the future burden of disease. The model assumes that a public health intervention could reduce mean risk factors to this level and sustain the reduction. Reference is made at the end of this report to a sample of studies where this has been achieved, and examples of the types of interventions that have been shown to be effective are given. In the author’s view, it is likely that initiatives which prevented populations in the future from reaching current risk levels (i.e. reaching levels 2% - 7% below the current mean) could well have the level of reduction in events predicted by the model. Populations which reduce their risk factors from the current mean, however, will have some residual effect from being at higher risk for a period of time. For example, a person who stops smoking after 40 years will not have the same risk as a person who never smoked, even though both will currently have a non-smoking status at that point in time. The residual effect of each factor and its half-life is currently unknown, and will only be available to the model through calibration as part of an initiative to reduce risk factors. This potential over-estimation of effect, however, could well be more than offset by an underestimation of revenue savings. The model takes into account the savings accrued from the acute admission only. For people who do not have a stroke or heart attack, there will be considerable indirect savings to the health system by avoiding the need for rehabilitation, homecare, disability payments, outpatient follow up, primary care episodes, drug costs etc, as well as the enhanced risk of subsequent events.

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2. Background a. The strategic intention NHS South Birmingham Primary Care Trust (PCT’s) is continually developing, in consultation with the local population, a strategic plan aimed at improving the health status of the people of South Birmingham and reducing health in-equalities. This strategy sets out very clearly the core strategic objectives of the organisation. A key component of the strategy is to continue reducing the level of inequality in health status across the South Birmingham’s population. This is demonstrated most powerfully by the fact that there is a significant gap in life expectancy between the most and least healthy population groups within the area. The strategy will require continuous updating in light of the significant financial pressures about to hit the NHS. Although the PCT has managed its finances well to date, the dual impact of a rapidly expanding demand for healthcare linked with significant financial pressures, make it incredibly important for the PCT to examine strategies for future demand management.

b. Coronary Heart Disease in NHS South Birmingham NHS South Birmingham fairly high levels of coronary heart disease in some parts of its population as a result of it industrial past, levels of deprivation in some parts of the City and the higher levels of risk experienced by some of its ethnic communities. For example the mortality (death rate) from CHD is 46% higher in men and 51% higher in women from South Asia when compared to the UK white population. South Asians have the highest overall and premature CHD mortalities of any UK ethnic group. Mortality rates are doubled in the 30-40 age groups and tripled in the 20-30 age group. An audit in one part of NHS South Birmingham showed the rates of heart attack under the age of 60 years were almost 4 times greater than expected in South Asian men and almost twice the number expected in South Asian women. These CHD rates occur despite a falling trend in the incidence of CHD in the general population. This suggests that more needs to be done to bring South Asians rates of heart disease down. The current risk of CHD is probably far greater than that predicted by the models used by many doctors to determine whether an individual should receive preventative therapy. Indeed, it is widely accepted that, at least in South Asian men, the risk of heart disease is underestimated by approximately 50%, so many individuals are still not receiving the preventative medication and advice they should. NB It must be noted that this mathematical model assumes national average risk levels across the population of Birmingham, in the absence of local data at this stage. It therefore underestimates current risk levels. Capacity is built into the model to adjust for higher levels of risk if local data becomes available. Both premature mortality rates (under 75 years) from all circulatory diseases and hospital admissions for heart attacks and strokes for all age groups in the West Midlands are statistically significantly worse than the national average position for England

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There are strong inequalities related to socio-economic deprivation and premature circulatory disease mortality. The pattern seen in men is stronger with rates in the deprived and most deprived quintiles being significantly higher than the affluent and most affluent quintiles and the national average position. In women, rates in the most deprived quintile are significantly higher than those in the most affluent quintile. The London Health Observatory, Health Inequalities Intervention Tool1 indicates that “narrowing the gap” in circulatory disease mortality in men and women would make a significant impact on improving life expectancy. It is estimated that reducing the rate of circulatory disease mortality in the most deprived quintile to the average rate of the remaining four quintiles would increase life expectancy in men by 0.66 years and women by 0.96 years NHS South Birmingham PCT is examining two key issues in the fight to improve the health status in its population and thus reduce or cap future demand for healthcare. The first is to explore mechanisms to reduce population level risk factors such as smoking, blood pressure, BMI, Cholesterol and Alcohol intake thus avoiding CVD related hospital admissions and premature deaths over the next five years. The second is to develop mechanisms to reduce healthcare costs in the next five years. These two actions, if achieved, would potentially go a long way towards helping the PCT to achieve their strategic goals to: • Improve health and reduce the gap in life expectancy • Develop services based more around the needs of individuals • Develop sustainable services. These strategic objectives, however, raise a crucial question. How can the purchaser in a health system save lives and save money? The key purpose of this report is to help the PCT to begin to examine the “invest to save” potential of these strategies inorder to clarify the business as well as the clinical case for further investment in prevention.

c. Shifting the focus: health and well being v diagnosis and treatment The “World Class” commissioning agenda is essentially aimed at encouraging the payer in the healthcare system to systematically review their investment portfolio and shift the focus of investment from healthcare to health or from curative to preventative interventions. The 2002 “World Health Report” pointed out that “virtually every major advance in health, at the level of a population, has involved the reduction or the elimination of risk”. Improvements in drinking-water supplies and sanitation during the 19th and 20th centuries were directly related to the control of the organisms that caused cholera and other diarrhoeal diseases. Mass immunisation programmes eradicated the scourge of smallpox from the planet and have reduced the risk to individuals and whole populations of infectious diseases such as poliomyelitis, yellow fever, measles and diphtheria by providing protection against the causative agents. Countless millions of premature deaths have been avoided as a result.

1

http://www.lho.org.uk/LHO_Topics/Analytic_Tools/HealthInequalitiesTool.aspx

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Today, in Europe, at least 33% of the entire disease burden is thought to be caused by five reducible population risk factors: tobacco, alcohol, blood pressure, cholesterol and obesity. Cardio-vascular risk is the new public health challenge. More than 75% of cardiovascular disease (the world’s leading cause of death) results from tobacco use, high blood pressure or cholesterol, or their combination. Overall, cholesterol causes more than 4 million premature deaths a year; tobacco causes almost 5 million, and high blood pressure 7 million worldwide. The future priorities for EU health policies, set out in the White Paper: Together for Health: A Strategic Approach for the EU 2008-2013, marks a continuing shift in healthcare policy from a clinical, curative, focus to the development of healthcare systems which focus more on the determinants of health. This policy direction is mirrored in the UK and is the underlying driver for the “Wanless” assumptions which set out the funding challenges for the NHS over the next decade and the subsequent World-Class Commissioning agenda. The idea of CHD risk factor reduction, in particular, has been understood as crucial to the improvement of health status at the level of the population since the 1980s. However, to date, no health system has managed to shift its main focus from the delivery of treatment services to the delivery of programmes aimed at population level risk reduction. Why? Because there are three extremely difficult questions which need to be addressed: • How could we re-engineer our current investment portfolio to release resources for upstream investment in health? • What would we invest in upstream, if we had the resources, to improve the health status of the population? • What might be the economic and clinical impact of such a switch in investment? This study begins to develop methodologies to answer question 3 and to some extent 2. It will be complementary to attempts to answer questions 1 and 2 through initiatives such as programme budgeting and marginal analysis which are core competencies in the world class commissioning initiative. Cardiovascular disease (CVD) continues to be a major health problem in NHS South Birmingham, the UK and in many other areas of the world. As stated above, NHS South Birmingham PCT has a strategy to reduce the gap in life expectancy across the population from the current levels. A major plank in this initiative would be to reduce the level of premature deaths in the most deprived areas of the population. As these premature deaths are largely related to cardio-vascular disease levels in deprived populations, this study seeks to quantify the potential impact that cardiovascular related risk reduction initiatives, embedded within an “Enhanced Public Health Programme” initiative, could have on the number of acute cardio-vascular related events such as heart attacks, strokes etc and consequent deaths, with a particular reference to the economic and clinical impact of such a switch in investment.

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d. NHS South Birmingham Enhanced Public Health Programmes Most of the building blocks for a systematic approach to CVD risk reduction in communities in England and Wales are currently in place or in the pipeline. Public health initiatives at a national, regional and local level are already engaged, including: smoke-free public facilities; healthy diets for children; five-a-day initiatives; promotion of exercise, leisure and sport; smoking cessation services; cholesterol monitoring and the use of statins; programmes to detect hypertension and control of blood sugar in primary care etc. These are well established in many areas. The CHD, Diabetes and Renal National Service Frameworks (NSFs) have developed the infrastructure for the early detection and rigorous treatment of early stage disease. The “QoF” framework has started the process of incentivising a focus on health and well-being in many areas. The introduction of widespread checks for CVD-related disease will begin to systemise the application of this infrastructure in a more targeted and comprehensive way. The task for the PCT is not to add to or duplicate this effort, but rather to use techniques such as social marketing, community engagement and regeneration to ensure that the most socially isolated, difficult to engage and highest risk populations gain equitable access to these initiatives, and to manage the co-ordination of the many layers of intervention to maximise impact and avoid duplication. An Improved Public Health Programme, targeted at the most deprived wards, could provide enhanced resources and support in the neighbourhood clusters where health is poorest. Examples of this approach have been used in Sheffield PCT, where they were developed as a flagship programme to tackle health inequalities in the local population (2005-2008). The programmes are systematic initiatives, based around a “Log Frame Planning Approach” leading to the production of a business plan in each of the targeted areas. These plans are developed and delivered in partnership with the local communities utilising local health data. The key principles of the approach are community engagement, empowerment and working in partnership with the voluntary sector. Joint, co-ordinated, locally owned approaches are intrinsic to the delivery of the programmes. Current examples of such programmes include initiatives to: • Tackle the wider determinants of health – housing, environment, education and employment • Promote healthy lifestyles • Increase the uptake of appropriate health services. Vulnerable groups, including some black and minority ethnic communities, tend to benefit from such initiatives, as programmes are usually designed around those with the greatest need. The programmes in Sheffield have a proven track record of building skills and confidence to enable participants to move into further learning, voluntary work or employment. The Health Champions Big Lottery programme starting this year will build on this work by supporting volunteers in local communities. This may be a model of interest to NHS South Birmingham.

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3. Study aims and objectives a. Aim of the study The aim of this study is to explore, in depth, the complex relationships between health, health improvement and health care in cardiovascular disease with a view to developing a mathematical model for comparing the cost effectiveness of prevention on the same terms as healthcare interventions. A key outcome from the study is to produce a robust, research-based, financial planning tool, which could be used to assess the “economic” argument for funding public health based prevention programmes in CVD-related illness on the same basis as treatment interventions.

b. Study objectives • To use individual level multivariate risk prediction equations, derived from Framingham and other studies, to estimate how many people in NHS South Birmingham PCT are likely to be admitted to hospital in the next five to ten years with CVD-related events such as heart attacks, strokes, heart failure and kidney disease • To estimate the potential financial impact of reductions in hospital admissions, on an “invest to save” basis, if the PCT or practice-based commissioning (PBC) consortia were to invest in public health based interventions to reduce cardiovascular risk at a population level.

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4. Study design / methodology A research based cost offset model has been developed from evidence drawn from a comprehensive, systematic review of research literature in the fields of cardiovascular related illness and prevention strategies aimed at reducing risk factors at a population level. The populations of General Practices across NHS South Birmingham Primary Care Trust (PCT) were entered into the spreadsheet based cost offset model, in terms of age and sex (this equated to around 286,251 adults). Estimation was made to determine how many people, in each age group, were likely to be diabetic. Population risk factors such as smoking rates, mean body mass index (BMI), mean total cholesterol, mean systolic blood pressure etc, were entered by age group for each GP population. The model uses a variant of the “Framingham Risk Equation� to calculate how many non-diabetic people in each age group were likely to have a heart attack or stroke in the next five years. In addition, heart failure and dialysis admission rates were estimated based upon risk factors for incidence. The United Kingdom Prospective Diabetes Study (UKPDS) risk engine 56 is used to calculate the risk of coronary heart disease (CHD) and stroke respectively in people with diabetes. The model deducts the number of people likely to die before reaching hospital and produces a predicted number of hospital admissions for each category over a fiveyear period. The final part of the calculation attaches a cost to the hospital activity using the UK Health Resource Grouping (HRG) tariffs. The predicted number of events in each of the populations is then compared with the actual number of events the previous year to validate the predictive accuracy of the model. The model then estimates the impact on the predicted activity numbers if mean risk levels, i.e. smoking rates, BMI, cholesterol levels etc, were reduced in each population. HRG tariffs are then used to convert the potential change in activity to levels of cost savings.

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5. Validation The Framingham study was a longitudinal cohort study carried out in the USA in which a group of people have been studied since the 1950s. Their lifestyle has been charted in terms of blood pressure, cholesterol levels, smoking habits etc, and their cardio-vascular health has been mapped in terms of unstable angina events, strokes, heart attacks etc. From this study a mathematical formula has been developed to show the relationship between these biological markers and cardio-vascular events. Framingham and derivative equations have been shown to be accurate predictors of cardio-vascular risk at the level of the individual worldwide. Different populations have minor adjustments to the precepts, but by and large a doctor has a pretty good idea of the chances of an individual having an acute event on the basis of these biological measures. The question arises however, how do we know if the predicted numbers of events will be accurate at a population level and in particular when applied to populations in the Birmingham PCT’s?

a. Validation against 5 South Yorkshire PCT (2003 data) To test the accuracy of the predictions in South Yorkshire, an exercise was carried out as part of the first iteration of the model in 2003. The population and risk factors for five PCT’s (Barnsley, North Sheffield, South East Sheffield, South West Sheffield and West Sheffield) were entered into the model. This produced the predicted number of events in the cream coloured bars in fig 8 below. This was then compared with the actual numbers of events by HRG codes from hospital admission data (2003) shown in the red coloured bars in fig 8 below. Fig 8 All acute MI events - actual v predicted adjusted (Brindle 2003) 4000 3500 3000 2500 2000 1500 1000 500 0 P o p. 1

P o p. 2

Actual

P o p. 3

Predicted

P o p. 4

P o p. 5

A ll P o ps.

Adjusted

As can be seen from fig 8, the model slightly under predicts events in the highest risk population (pop 1 Barnsley), is very accurate in pop 2 (North Sheffield PCT) and pop 3 (South East Sheffield PCT), and over predicts in lower risk populations, i.e. pop 4 (South West Sheffield PCT) and pop 5 (West Sheffield PCT). These findings are exactly in line with the literature on Framingham as applied to Northern European populations. Brindle et al produced an adjustment for low risk populations as shown in the blue bar on fig 8. (This was the forerunner of the Q Risk formulae.) When this is applied, the predictions in pop 4 and pop 5 increase in accuracy.

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The problem is that it is difficult to know at what point a population becomes a high risk, medium or low risk group, particularly at the level of the GP.

b. Validation against the three Birmingham PCTs (2008 data) Because of the lack of local risk data at this point in time, the model currently uses national risk data as a default. Because Cardio-Vascular risk in Birmingham is generally higher than the national average, the model is currently under-predicting activity in this area. It is fairly easy to weight the populations in the model to adjust for this but no weighting formulae was available from the PCT at the time of writing this report. More accurate risk data will however be required in the future in-order to measure the impact of any interventions on mean risk. Fig 9

All acute CHD events - actual v predicted Birmingham PCTs 18000 16000 14000 12000 10000 8000 6000 4000 2000 0 16-24

25-24

35-44

45-54

Actual

55-64

55-74

75+

A ll events

Predicted

One of the problems we found with the application of the model in South Yorkshire was the tendency in the model to slightly over predict CKD activity. We have not adjusted for this yet because there is a known under-diagnosis of CKD in the UK, with the rates of dialysis being as low as 70 per 100,000 is some localities compared with 100 per 100,000 in Europe and 200 per 100,000 in the US. The introduction of electronic GFR reporting on routine blood tests introduced though the Renal National Service Framework is correcting this, but the full impact has not yet been felt in many areas. In addition, it is known that a proportion of kidney patients die of cardio-vascular related events before they reach dialysis. The model does not deduct this number at this stage. Again, the introduction of the care protocols within the Renal NSF will begin to reduce this number, bringing the actual number of events in the future nearer to the predicted number in the model. Finally, the actual events currently include only hospital-based dialysis patients. It is known that up to 20% of patients receive community-based dialysis in some areas. The CKD activity data from the Birmingham PCT’s related to episodes rather than patients. We have therefore simply assumed that predicted and actual activity would match for the purpose of validation at this stage.

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The correlation between the predicted number of myocardial infarction and stroke events and actual events is shown in figs 10 and 11 below. Again predictions appear to be slightly lower at this stage with un-weighted risk factors especially in younger age groups. This is probably a reflection of the high risk levels in some ethnic groups referred to earlier in the report. Fig 10

All acute MI events - actual v predicted Birmingham PCT's

1000 800 600 400 200 0 16-24

25-24

35-44

45-54

Actual

55-64

55-74

75+

A ll events

Predicted

Fig 11

All acute stroke events - actual v predicted Birmingham PCTs 1000 800 600 400 200 0 16-24

25-24

35-44

45-54

Actual

55-64

Predicted

17

55-74

75+

A ll events


6. Results (NHS South Birmingham PCT’s level) The first outcome of the model is to compare the estimated number of people likely to suffer from a heart attack, a stroke, heart failure or chronic kidney failure in each practice or deprived population with the actual number for the previous year 2007/08, as described above. The assumption for the financial planning exercise is that if the predictions are relatively accurate at the current risk factor level, then predictions based upon high risk factor levels and lower risk factor levels should be equally accurate. This allows the testing of “what if scenarios”. For example, what would happen to the number of heart attacks, strokes, heart failure or chronic kidney failure episodes if the risk factors in the population were 3% - 4% lower? What would happen if the risk factor levels were 5% - 6% lower? The second outcome of the model is to estimate the consequence of potential risk reduction in three areas: • Acute events / admissions avoided • Premature deaths avoided • Reduction in acute admission costs The model tests out two scenarios for the purpose of this report, although any combination of assumptions could be modelled. • Scenario 1: More ambitious targets of risk reduction of the order of 5%-6% • Scenario 2: Moderate reductions in risk of the order of around 3%-4%

a. Estimated acute events avoided (PCT level) If the mean risk levels in the adult population of NHS South Birmingham were reduced as a result of more co-ordinated and targeted primary prevention (lifestyle interventions) or secondary prevention (primary care interventions) to the levels shown in fig 12, then the model estimates that the number of acute events, including heart attacks, strokes, kidney failure and heart failure, could reduce substantially over a five year period. Fig 12 Risk factor

Scenario 1: Optimistic target from the literature -5% reduction -0% reduction -13% reduction -6% reduction +6% increase -5% reduction

Obesity (indicated by mean BMI) HBA1c level in Type 2 diabetics (mean updated) Smoking rates Mean total cholesterol (mmol/l) Mean HDL cholesterol (mmol/l) Mean systolic blood pressure (SBP mmHg)

Scenario 2: Less ambitious target from the literature -2% reduction -0% reduction -10% reduction -4% reduction +4% increase -3% reduction

The model assumes that if a target were set as shown in fig 12, it would take some time for the interventions to move the mean risk level to that target level. For example if we assume that current smoking prevalence is 20%. A reduction in mean smoking prevalence of 5% in 5 years would equate to a reduction from 20% prevalence to 19% prevalence. If the intervention were assumed to achieve a 1% reduction each year, the model would assume that prevalence dropped to 19.8% after year one, 19.6% after year 2, 19.4% after year three 19.2% after year 4 and to19% at year 5.

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Fig 13 below shows the estimated impact on the numbers of acute events over a five-year period if the target reduction in risk factors were achieved in either scenario 1 or scenario 2. If enhanced public health programmes could reduce mean risk by around 3% – 6%, the number of acute events CHD related events could fall by between 1,585 and 1,041 per annum, depending upon the level of reduction. Fig 13 Estimated reduction in annual acute events/admissions over a five year period assuming 20% move toward risk factor reduction target per annum 6,000 5,000 4,000 3,000 2,000 1,000 0 Baseline

Year 1

Year 2

Scenario 1

Year 3

Year 4

Year 5

Scenario 2

The cumulative effect of such a programme is estimated in fig 14 below. Fig 14 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative acute admission events avoided 0 4,756 3,122

It is estimated that relatively small reductions in population level risk factors could lead to a cumulative reduction in acute events of between 3,122 and 4,756 over a period of five years.

b. Estimated deaths avoided (PCT level) Clearly a percentage of people who have a heart attack or a stroke die before they reach hospital. Using the same risk reduction assumptions as with the acute events, the model shows that if there are fewer events, not only will there be fewer deaths, but reduced risk levels will lead to a lower percentage of patients dying as a result of the acute events. If the levels of risk reduction were achieved at the level of the PCT, the estimated number of premature deaths avoided each year after five years is between 256 and 385. See fig 15.

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Fig 15 Estimated reduction annual premature deaths over a five year period assuming 20% move toward risk factor reduction target per annum 2,000 1,500 1,000 500 0 Baseline

Year 1

Year 2

Scenario 1

Year 3

Year 4

Year 5

Scenario 2

The estimated cumulative number of deaths avoided is shown in fig 16. Again, this assumes that risk reduction targets are achieved at a level of 20% per annum over 5 years. Fig 16 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative deaths avoided 0 1,155 769

c. Estimated revenue consequences (PCT level) Clearly, if public health interventions can impact upon the number of acute events, then there will be an impact on the cost of acute hospital admissions and the future capacity required for acute care in this area. The revenue savings could take different forms, depending on the demographic profile of the population. For example, age is a key risk factor in CVD-related illness. As the population ages the number of acute events will rise. Reduction in lifestyle-related population risk factors may simply counteract this trend, thus stabilising demand at current levels and avoiding the need for significant extra investment. If, on the other hand, demographic pressures are relatively stable, the revenue consequences of reduced numbers of events could accrue as savings. Again, the model could show the impact of the ageing of the population to calculate this effect. Costs in the model have been restricted to the HRG tariff for acute admissions avoided only at this point. Clearly there are considerable indirect costs to both the PCT and society of, say, a stroke, over and above the emergency admission cost. Further work is under way to extend the cost impact of the model. If the numbers of events avoided reach the levels outlined in fig 13, the revenue consequences could be of the order shown in fig 17 below:

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Fig 17 Estimated reduction in acute hospital admission costs over a five year period assuming 20% move toward risk factor reduction target per annum £18,000,000 £16,000,000 £14,000,000 £12,000,000 £10,000,000 £8,000,000 £6,000,000 £4,000,000 £2,000,000 £0 Baseline

Year 1

Year 2

Scenario 1

Year 3

Year 4

Year 5

Scenario 2

The more optimistic scenario of a reduction in population level risk factors of the order of 5% - 6% could lead to revenue saving of up to £4.2 million per annum after 5 years (assuming that 20% of the target was achieved each year). The more pessimistic scenario of a 3% - 4% reduction could reduce revenue costs by around £2.9 million per annum after 5 years. Non-recurrent cumulative savings could be of the order of £12.8 million for scenario 1 or £8.7 million for scenario 2. See fig 18. Fig 18 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative acute admission costs avoided 0 12.8 million 8.7 million

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7. Results (1st Quintile level) a. Estimated acute events avoided (Quintile level 1) Clearly it may not be possible for NHS South Birmingham PCT to fund a CVD reduction programme aimed at the whole population in the first instance. If the mean risk levels in the adult population of the top quintile of the Super Output Areas of Deprivation in NHS South Birmingham were reduced as a result of more coordinated and targeted primary prevention (lifestyle interventions) or secondary prevention (primary care interventions) to the levels shown in fig 12, then the model estimates that the number of acute events, including heart attacks, strokes, kidney failure and heart failure, could reduce substantially over a five-year period. Figs 19 and 20 below show the potential reductions achievable if an enhanced public health programme concentrated on the central NHS South Birmingham population in the top deprivation quintile only, in the first instance, over a five year period (population 5,903 males and 5,672 females). In this scenario it may be possible to avoid between 369 and 231 acute events per annum at the end of the five-year period and reduce annual acute admission costs by between ÂŁ600k and 950k. Fig 19

2,500

Estimated annual reduction in acute events/admissions from qunintile 1 over a five year period aassuming 20% move toward risk factor reduction target per annum

2,000 1,500 1,000 500 0 Baseline

Year 1

Year 2

Scenario 1

Year 3

Year 4

Year 5

Scenario 2

The cumulative effect of such a programme is estimated in fig 20 below. Fig 20 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative acute admission events avoided 0 1,108 694

I

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b. Estimated deaths avoided (Quintile level 1) Fig 21 shows the potential premature deaths avoided in Quintile 1, if risk reduction targets were met. Fig 21 Estimated reduction in premature deaths from quintile 1 over a five year period assuming 20% move toward risk factor reduction target per annum 70 60 50 40 30 20 10 0 Baseline

Year 1

Year 2

Year 3

Scenario 1

Year 4

Year 5

Scenario 2

Fig 22 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative deaths avoided 0 41 27

An enhanced public health programme in the most deprived quintile of NHS South Birmingham could achieve a reduction in premature deaths by around 14 per annum in five years if the more optimistic risk reduction targets were met. This could have a significant impact on the gap in life expectancy.

c. Estimated revenue consequences (Quintile level 1) If the numbers of events avoided reach the levels outlined in fig 12, the revenue consequences in quintile 1 alone could be of the order shown in fig 23 below: Fig 23 Estimated reduction in acute admission costs from quintile 1 over a five year period assuming 20% move toward risk factor reduction target per annum £6,000,000 £5,000,000 £4,000,000 £3,000,000 £2,000,000 £1,000,000 £0 Baseline

Year 1

Year 2

Scenario 1

23

Year 3

Scenario 2

Year 4

Year 5


The more optimistic scenario of a reduction in population level risk factors of the order of 5% - 6% could lead to revenue saving of up to £950k per annum after 5 years (assuming that 20% of the target was achieved each year). The more pessimistic scenario of a 3% - 4% reduction could reduce revenue costs by around 600k per annum after 5 years. Non-recurrent cumulative savings could be of the order of £2.8m for scenario 1 or £1.7m for scenario 2. See fig 24. Fig 24 Scenario Current risk Scenario 1 Scenario 2

5 year accumulative acute admission costs avoided 0 £2.8m £1.8m

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8. Results (1st and 2nd Quintile level) a. Estimated acute events avoided (Quintile level 1&2) If a pilot were to cover the top two quintiles in NHS South Birmingham (population 31,685 males and 31,885 females) the impact is estimated as follows: Fig 25 Estimated annual acute events/admissions avoided in qunintile 1 & 2 over a five year period assuming 20% move toward risk factor reduction target per annum 3,000 2,500 2,000 1,500 1,000 500 0 Baseline

Year 1

Year 2

Scenario 1

Year 3

Year 4

Year 5

Scenario 2

The cumulative effect of such a programme is estimated in fig 26 below. Fig 26 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative acute admission events avoided 0 1,781 1,142

Figs 25 and 26 above show the potential reductions achievable if an enhanced public health programme concentrated on the top two quintiles over a five-year period. In this scenario it may be possible to avoid between 594 and 381 acute events per annum after a five-year period.

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b. Estimated deaths avoided (Quintile level 1&2) Fig 27 shows the potential premature deaths avoided in Quintile 1&2, if risk reduction targets were met. Fig 27 Estimated annual deaths avoided in quintile 1 & 2 over a five year period assuming 20% move toward risk factor reduction target per annum 400 350 300 250 200 150 100 50 0 Baseline

Year 1

Year 2

Year 3

Scenario 1

Year 4

Year 5

Scenario 2

Fig 28 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative deaths avoided 0 240 160

An enhanced public health programme covering the top two quintiles could achieve a reduction in premature deaths by around 80 per annum if the more optimistic risk reduction targets were met.

c. Estimated revenue consequences (Quintile level 1&2) If the numbers of events avoided reach the levels outlined in fig 12, the revenue consequences in quintiles 1 and 2 alone could be of the order shown in fig 29 below: Fig 29 Estimated revenue saving in quintile 1 & 2 over a five year period assuming 20% move toward risk factor reduction target per annum £8,000,000 £7,000,000 £6,000,000 £5,000,000 £4,000,000 £3,000,000 £2,000,000 £1,000,000 £0 Baseline

Year 1

Year 2

Scenario 1

26

Year 3

Scenario 2

Year 4

Year 5


The more optimistic scenario of a reduction in population level risk factors of the order of 5% - 6% could lead to revenue saving of up to £1.5m per annum after 5 years (assuming that 20% of the target was achieved each year). The more pessimistic scenario of a 3% - 4% reduction could reduce revenue costs by around £1.0m per annum after 5 years. Non-recurrent cumulative savings could be of the order of £4.7 million for scenario 1 or £3.1 million for scenario 2. See fig 30. Fig 30 Scenario Current risk Scenario 1 Scenario 2

5 year cumulative acute admission events avoided 0 £4.7 million £3.1 million

9. Conclusion Clearly any combination of population and risk reduction programme can be modelled. The more defined the population targeted, the more cost effective the risk reduction programme will be. If a population such as Quintile 1&2 were selected (around 63,570), then the first task would be to target the most “at risk” of this “at-risk” group. If the programme started with men aged 45 – 65, the target population would reduce to around 6,343 people. If around 40% of these people are already known to their GP and have had risk assessment, then the number reduces to around 4,613. Persuading half of these people (3,806) to take a Framingham-based risk assessment and ensure that any identified risks are responded to, e.g. high cholesterol, BP and BMI, will go a long way towards meeting the risk reduction target. Clearly if a large proportion of these people were from South Asian communities the impact would be magnified. Other programmes aimed at helping people not to reach those risk levels in the future will enhance the sustainability of the health improvement. Clearly, the larger the target population, the larger the initial investment in risk reduction strategies and the larger the financial risk as well as the benefits.

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10. Risk level reduction How would the PCT go about achieving the risk reduction levels modelled in this exercise? There is growing evidence worldwide that these risk factors are reducible. Some examples of interventions are shown below:

a. Smoking cessation – studies A study published in Drug and Alcohol Review2 (November 2006) demonstrated that many national policies were quite effective. For example, they found that a 10% increase in cigarette prices, through taxation for example, will reduce overall cigarette smoking by 2.5% to 5.0%. Similarly, restrictions in smoking, such as workplace smoking bans, reduced smoking prevalence among adults by 5%, while it reduced cigarette consumption among continuing smokers by 10%. Changes to health information and counter advertising led to significant reductions in cigarette smoking. Initial declines in smoking of between 4% and 9% in the short term and longer-term cumulative declines of 15 – 30% were achieved. Bans on advertising and promotion, in high-income countries, have been shown to reduce tobacco consumption by over 6%. This study concluded that partial bans have little impact on smoking behaviour. Clearly this type of approach is beyond the scope of the PCT, although the principles might be useful in re-enforcing the messages in high risk communities. A review of studies published in The Annals of Internal Medicine3 (2006) showed that at 1 year after cessation, quit rates were 11.2% for low-dependence smokers who were receiving a placebo. Rates were 19.5% for those receiving 2-mg nicotine replacement gum, and 18.4% for those receiving 4-mg nicotine gum (P _ 0.20 for linear trend). For high-dependence smokers, quit rates at 1 year were 6.1%, 15.7% and 20.7% respectively. A Polish study in 20074 used a systematic review to show that the nonpharmacological smoking cessation methods available in Poland, namely the physician's advice and individual or group counselling, increased the probability of smoking cessation and smoking abstinence for 12 months to up to twice the level of those trying to quit unaided. The number of patients who need to be treated for each quitter was estimated at about 30 for more intensive counselling and 60 for straightforward advice from a clinician. A meta-analysis of the effectiveness of smoking cessation therapies in 20065 examined studies where nicotine gum or NRT patches, nicotine inhalers, nasal sprays and lozenges, or a combination of these was used. The control interventions included placebo, no treatment and other pharmacological agents. The duration of treatment, where reported, ranged from 2 weeks to 24 months. 2 Prabhat Jha, Frank J. Chaloupka,: Reducing the burden of smoking world-wide: effectiveness of interventions and their coverage, Drug and Alcohol Review (November 2006), 25, 597 – 609 3 Ranney L. Melvin C Systematic Review: Smoking Cessation Intervention Strategies for Adults and Adults in Special Populations Ann Intern Med. 2006; 145:845-856. 4 Bala MM, Lesniak W, Efficacy of non-pharmacological methods used for treating tobacco dependence: meta-analysis. Pol Arch Med Wewn. 2007 Nov-Dec; 117(11-12):504-11. 5 Wilson K. Dimoulas P: Effectiveness of smoking cessation therapies: a systematic review and meta-analysis, BMC Public Health.2006;6:300

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The study demonstrated that nicotine replacement therapy (NRT) significantly improved smoking cessation rates at 1 year, compared with any control. (OR 1.71, 95% CI: 1.55, 1.88, p<0.0001). The results were similar for NRT versus placebo only studies (OR 1.78, 95% CI: 1.60, 1.99, p<0.0001; 49 studies), NRT gum (OR 1.60, 95% CI: 1.37, 1.86, p<0.0001; 33 studies) and NRT patch (OR 1.63, 95% CI: 1.41, 1.89, p<0.0001; 23 studies).

b. Smoking cessation – guidance Comprehensive evidence based recommendations on the treatment of tobacco dependence was produced by the WHO in June 20016. They recommend the use of 3 main types of intervention: • pharmacotherapy • intensive support delivered by treatment specialists • brief opportunistic interventions Any initiative in NHS South Birmingham could be based on this guidance.

c. Obesity – studies A study published in the International Journal of public health in 20077 undertook a systematic review (with meta-analysis) and included studies which were randomised clinical trials of lifestyle interventions in overweight and obese people. The minimum observation period was one year. 13 studies were selected in the prevention of obesity and 17 in the treatment of obesity. The study concluded that lifestyle interventions were efficacious in the mid- to longterm prevention and treatment of obesity, leading to a significant reduction in body weight and cardiovascular risk factors. A Cochrane review examining the impact of exercise on obesity8 examined 43 studies including 3,476 participants. The studies were primarily randomised controlled trials that examined body weight change using one or more physical activity. The review concluded that exercise combined with diet resulted in a greater weight reduction than diet alone. A study looking at the impact of weight reduction as a primary prevention for strokes9 suggest that obesity seems to be associated with an increased risk of stroke and a weight loss may lead to a reduction of stroke occurrence.

d. Obesity – guidance The Royal Pharmaceutical Society of Great Britain produced comprehensive guidance on the management of obesity in 200510. The guidance included information on weight loss; reducing energy intake through a diet relatively low in saturated fat; and increased physical activity. 6

www.euro.who.int/document/e73285.pdf Galani C., Schneider H. Prevention and treatment of obesity with lifestyle interventions: Review and meta-analysis. International Journal of Public Health. 52(6) (pp 348-359), 2007. 8 Shaw K, Gennat H, O’Rourke P, Del Mar C. Exercise for overweight or obesity (Review) The Cochrane Library 2008 Issue 3 9 Curioni C, André C, Veras R. Weight reduction for primary prevention of stroke in adults with overweight or obesity, BMJ 2006 154-156 10 Practice guidance: obesity Royal Pharmaceutical Society of Great Britain July 2005 7

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Similarly a cross-government strategy for the NHS in England11 was introduced in May 2008. This strategy focuses on 5 key areas in the reduction of obesity. These are: the healthy growth and development of children; promoting healthier food choices; building physical activity into our lives; creating incentives for better health; and personalised advice and support.

e. Cholesterol – studies A Cochrane review of twenty-seven studies12 (including 40 intervention arms and 30,901 person-years) showed that although there was no significant effect from cholesterol-lowering interventions on total mortality (rate ratio 0.98, 95% CI 0.86 to 1.12), there was a trend towards protection from cardiovascular mortality (rate ratio 0.91, 95% CI 0.77 to1.07), and significant protection from cardiovascular events (rate ratio 0.84, 95% CI 0.72 to 0.99). A study published in 200713 supports the conclusions from previous meta-analyses that cholesterol lowering is clinically beneficial in patients with CHD or at elevated CHD risk. Among all patients, for every 1-mmol/L decrease in total cholesterol, there was a 17.5 reduction in relative risk for all-cause mortality; 24.5 %, for CHD-related mortality; and 29.5% for any CHD event. Corresponding reductions for every 1mmol/L decrease in LDL-cholesterol were 15.6%, 28.0%, and 26.6%, respectively. Similar relationships were observed in patients without CHD. A 2008 Cochrane Review of dietary advice14 concluded that dietary advice reduced total serum cholesterol by 0.16 mmol/L (95% CI 0.06 to 0.25) and LDL cholesterol by 0.18 mmol/L (95% CI 0.1 to 0.27) after 3-24 months. Mean HDL cholesterol levels and triglyceride levels were unchanged.

f. Cholesterol – guidance Advice on cholesterol-lowering strategies can be found in the Third Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults15. Diet therapy is the primary method of lowering cholesterol; exercise and weight control are its components. Drug therapy should be considered for patients at high risk of heart disease who do not respond to dietary therapy.

g. Systolic blood pressure – studies A Cochrane review of the effect of modest salt reduction on blood pressure16 examined twenty trials of individuals with elevated blood pressure (n=802) and 11 trials in individuals with normal blood pressure (n=2220). In individuals with elevated blood pressure the median reduction in urinary sodium was 78 mmol/24h (4.6 g/day

11

Healthy Weight, Healthy lives A Cross Government strategy for England NHS - Guidance May 2008 Hooper L, Summerbell CD, Higgins JPT, Thompson RL, Clements G, Capps N, Davey Smith:” Reduced or modified dietary fat for preventing cardiovascular disease”, Cochrane Database of Systematic Reviews 2000, Issue 2. Gould AL, Davies GM, Alemao E, Yin DD, Cook JR. Cholesterol reduction yields clinical benefits: meta-analysis includin recent trials. Clin Ther. 2007 May; 29(5):778-94. 14 Brunner EJ, Rees K, Ward K, Burke M, Thorogood M. Dietary advice for reducing cardiovascular risk (Review). The Cochrane Library 2008 Issue 3 15 (Adult Treatment Panel III) National Heart, Lung, and Blood Institute National Institutes of Health NIH Publication No. 02-5215, September 2002 16 He FJ, MacGregor GA. Effect of longer-term modest salt reduction on blood pressure. The Cochrane Library 2008 Issue 3 12

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of salt), the mean reduction in blood pressure was -5.06 mmHg (95%CI:-5.81 to 4.31) for systolic and -2.70 mmHg for diastolic. A study examining the long term effect of weight reduction on blood pressure17 found that reduction of BP was higher in patients treated with weight loss diets (systolic BP [SBP]: weighted mean difference [WMD], -6.3 mm Hg; diastolic BP [DBP]: WMD, -3.4 mm Hg) or Orlistat (SBP: WMD, -2.5 mm Hg; DBP: WMD, -2.0 mm Hg). Systolic BP increased with sibutramine treatment (WMD, 3.2 mm Hg).

h. Systolic blood pressure â&#x20AC;&#x201C; guidance Guidance on dietary interventions to control blood pressure can be found in the British Hypertension Society Guidelines for the Management of Hypertension18. The document recommends engagement in regular aerobic physical activity such as brisk walking (30 min per day, most days of the week); alcohol consumption of no more than 3 units/day in men and no more than 2 units/day in women; consumption of a diet rich in fruit and vegetables (at least five portions per day); and consumption a diet with reduced content of saturated and total fat.

17 Horvath K. Jeitler K. Siering U. Stich AK. Skipka G. Long-term effects of weight-reducing interventions in hypertensive patients: systematic review and meta-analysis. Archives of Internal Medicine. 168(6):571-80, 2008 Mar 24. 18 http://www.bhsoc.org/Latest_BHS_management_Guidelines.stm

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The World Health Organisation WHO and International society of Hypertension ISH guidelines19 demonstrate how treating hypertension has been associated with about a 40% reduction in the risk of stroke and about a 15% reduction in the risk of MI. It recommends lifestyle modifications which reduce incidence of hypertension: weight loss, physical activity, moderation in alcohol intake, a diet with increased fresh fruit and vegetables, reduction of dietary sodium intake, increased dietary potassium intake.

i. CHD – diet – studies A meta-analysis of observational studies on fish intake and coronary heart disease20 compared fish consumption with little to no fish consumption in diets. They found that this was associated with a relative risk of 0.83 (95% confidence interval 0.76 to 0.90; p <0.005) for fatal CHD and a relative risk of 0.86 (95% confidence interval 0.81 to 0.92; p <0.005) for total CHD. The results indicate that fish consumption is associated with a significantly lower risk of fatal and total CHD. These findings suggest that fish consumption may be an important component of lifestyle modification for the prevention of CHD. A review of studies on diet and CHD21 recommended that total fat intake should not constitute more than 30% of calories, cholesterol intake not more than 300 mg per day and that regular fatty fish consumption and a high intake of fresh fruits and vegetables is recommended. Moderate alcohol intake can be protective.

j. CHD – exercise – studies Using a random effects model, the effects of aerobic exercise on glycosylated hemoglobin (HbA1c) (mean, 95% confidence interval, -0.9%, -1.9% to 0.03%), resting systolic blood pressure (-6.9 mm Hg, -9.1 to -4.6 mm Hg), low-density lipoprotein cholesterol (-3.1 mg/dL, -6.1 to 0 mg/dL), and body mass index (-1.3 kg/m(2), -2.5 to -0.1 kg/m(2)) were either statistically significant or demonstrated a trend for statistical significance22. The changes corresponded to estimated 5-year reductions in CHD mortality of 14%, 17%, 1.5%, and 5%, respectively. The results of this review reinforced the idea that aerobic exercise is an important non-pharmacological intervention for improving selected CHD risk factors. A meta-analysis of the independent relationship between physical activity and coronary heart disease23 concluded that the relative risk of the independent relation of physical inactivity to CHD is 1.37, with a 95 percent confidence interval (1.27-1.48) A meta-analysis of physical activity in the prevention of coronary heart disease24 concluded that the relative risk of death from coronary heart disease was 1.9 (95% confidence interval 1.6-2.2) for sedentary compared with active occupations. 19

http://www.ish-world.com/default.aspx?Guidelines Whelton SP, He J, Whelton PK, Muntner P, Meta-analysis of observational studies on fish intake and coronary heart disease. Am J Cardiol. 2004 May 1;93(9):1119-23. 21 Hughes K. Diet and coronary heart disease--a review. Annals of the Academy of Medicine, Singapore. 24(2):224-9, 1995 Mar. 22 Kelley GA. Kelley KS Efficacy of aerobic exercise on coronary heart disease risk factors. Prev Cardiol. 2008 Spring;11(2):715. 23 Eaton CB. Relation of physical activity and cardiovascular fitness to coronary heart disease, Part I: A meta-analysis of the independent relation of physical activity and coronary heart disease. Journal of the American Board of Family Practice. 5(1):3142, 1992 Jan-Feb 24 Berlin JA. Colditz GA. A meta-analysis of physical activity in the prevention of coronary heart disease. American Journal of Epidemiology. 132(4):612-28, 1990 Oct. 20

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An American study on physical activity levels and coronary heart disease25 demonstrated that moderate intensity, dynamic, endurance-type of exercise (such as walking or jogging about 20 miles per week) or at least one hour of intermittent hard physical labour are required to obtain the optimal effect of exercise on coronary heart disease rates.

k. CHD – exercise – guidance The European Society of Cardiology “Cardio metabolic risk in essential hypertension”26 argues that the minimum requirements for long-term effectiveness include caloric restriction in the range of 500-1000 Kcal with a 7%-10%, weight loss in 12 months and regular aerobic exercise of 30-45minutes/day. The European Guidelines on Cardiovascular Disease Prevention27 issued by the European Atherosclerosis Society 2007 advocates: • • • • • •

Avoidance of tobacco. Adequate physical activity (at least 30 min per day). Healthy food choices. Avoiding overweight. BP below 140/90 mmHg. Total cholesterol below 5 mmol/L (∼200 mg/dL).

25 Leon AS. Physical activity levels and coronary heart disease. Analysis of epidemiologic and supporting studies. Medical Clinics of North America. 69(1):3-20, 1985 Jan. 26 http://www.escardio.org/communities/councils/ccp/e-journal/volume5/Pages/vol5n37.aspx 27 http://www.eas-society.org/athero_societies_associations.asp

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South_BirminghamPCT_CVD_ModellingReporOct2009  

Professor Malcolm David Whitfield 2009 Summary Report Modelling the potential impact of Enhanced Public Health Programmes on population leve...