The global syndemic of OBESITY

The global syndemic of obesity

Obesity is a complex, chronic disease, which can cause a multitude of other diseases with severe morbidities and mortality. Obesity is rising worldwide and has a disturbing economic burden, both direct and indirect, which continues to rise.1

Obesity figures from 1975 to 2014 confirm that we are getting fatter, and it is predicted that by 2025, global obesity prevalence will reach 18% in men and 21% in women. Severe obesity will affect about 6% of men and 9% of women. Swinburn et al call this the ‘global syndemic of obesity’.2

A syndemic is not merely a comorbidity. Syndemics are characterised by biological and social interactions between conditions and states, interactions that increase a person’s susceptibility to harm or worsen their health outcomes.3

Swinburn et al compared the data (1975 to 2014) of more than 19.2 million participants (9.9 million men and 9.3 million women) aged 18 years or older whose height and weight had been measured. Data in 186 countries, which cover 99% of the world’s population, were included. 2

They found:

» Global age-standardised mean body mass index (BMI) increased from 21.7kg/m2 in 1975 to 24.2kg/m2 in 2014 in men, and from 22.1kg/m2 in 1975 to 24.4kg/m2 in 2014 in women

» Regional mean BMIs in 2014 for men ranged from 21.4kg/m2 in central Africa and south Asia to 29.2kg/m2 in Polynesia and Micronesia

» Age-standardised prevalence of obesity increased from 3.2% in 1975 to 10·8% in 2014 in men, and from 6.4% to 14.9% in women. About 2% of the world’s men and 5% of women were severely obese (BMI ≥35kg/m2)

» Globally, prevalence of morbid obesity was 0.64% in men and 1.6% in women.

In South Africa, 70% of women, 35% of adult men and 13% of children fall into the obese and overweight category. Only 30% engage in regular formal physical activity and 82% consumer high calorie low nutritional and processed fast foods. Do not wait – more than ever, it is important to lose weight, according to Dr Gary Hudson, a specialist physician with an interest in weight management.4

Although it is not the most accurate, Dr Hudson said that BMI is still a very important clinical measurement, and that even those with a BMI of just >25kg/m2, which is literally just above the normal weight range, seem to correlate with a higher incidence of serious disease, particularly when combined with a comorbidity such as hypertension.4

Swinburn et al too caution that high BMI is an important risk factor for cardiovascular (CV) and kidney diseases, diabetes, some cancers, and musculoskeletal disorders.2

Figure 1: EOSS obesity scoring tool

Obesity

Stage 0 Stage 1 Stage 2 Stage 3 Stage 4

Medical absent pre-clinical risk factors comorbidity end-organ damage end-stage Mental absent mild moderate severe end-stage Functional absent mild moderate severe end-stage

What drives obesity?

Obesity, explain Lean et al, is not just a state of excess of body fat or BMI above an arbitrary cut-off. It should be viewed as a disease process of excess body fat accumulation that has interacting (epi-) genetic and environmental causes as well as multiple pathological consequences. Obesity tends to run in families, they add, and is augmented by environmental drivers. These include poor education and socioeconomic situations.5

Multidisciplinary approach to weight management

The basic weapons against many diseases, including obesity is diet and exercise, weapons available to most of our patients but not nearly enough take advantage of them, stressed Dr Hudson.4

Speaking at the South African launch of liraglutide on 6 February 2021, Dr Sean Wharton: Co-chair of the 2020 Canadian Obesity Guidelines, said obesity should be managed using evidence-based chronic disease management principles.6

People who are living with obesity should have access to evidence-informed interventions, which should include:6

» Medical nutrition therapy

» Physical activity

» Psychological interventions

» Pharmacotherapy

» Surgery.

The authors of the guideline developed a five step approach to obesity management:6

Step 1: Ask

Be aware of bias. Do not assume that all patients living with obesity are prepared to initiate obesity management. Ask patients’ permission to discuss obesity before proceeding.6

Step 2: Assess

Measure BMI and waist circumference. Remember that measuring the BMI is not the most important, said Dr Wharton, but should rather be used to measure health parameters for epidemiological purposes. Measure the waist circumference in individuals with a BMI 25kg/ m2-35kg/m2. It is not necessary to measure waist circumference in BMI <25kg/m2, and in a BMI > 35kg/m2 because it is well-known that there will be an increased waist circumference.6

If you have a patient with a BMI of 28kg/m2 and the waist circumference is elevated, that is where the risk is. He added that overweight white males (BMI 25kg/m2-35kg/m2) often have significantly elevated waist circumferences and have a risk of metabolic conditions such as coronary artery disease.6

He recommended taking a comprehensive history of the patient and identify some of the root causes why they may have gained weight in the past, what were the complications and what are some of the barriers to treatment. Other measurements to do are blood pressure, fasting plasma glucose (FPG), HbA1c and lipid profile.6

Dr Wharton said they use the Edmonton Obesity Staging System (EOSS) staging tool (see figure 1) to determine the severity of the person’s elevated weight. If there are a lot of medical conditions associated with their elevated weight, they are at a higher stage, and that determines how aggressive we will be with our treatment, he explained.6

Step 3: Advise

No one loses weight unless there are less calories. Medical nutrition therapy or having an appropriate diet (see box 1 for recommendations is a cornerstone, as is physical activity (see box 2 for recommendations), said Dr Wharton.6

The important part is the ability to maintain the dietary options and physical activity is rooted in three major interventions:6

» Psychological: Weight loss is not just about willpower, it is about how to maintain behavioural aspects based on emotional eating, coping and strategies; and managing sleep, time and stress. Cognitive behavioural therapy is the most important treatment option but cannot be done easily by the individual on their own. It often requires the assistance of a healthcare provider who is trained in psychological intervention.

» Pharmacotherapy: In Canada, there are three interventions approved for weight management: Liraglutide, naltrexone/ bupropion in a combination tablet), and orlistat. Please note that nalteroxone/ bupropion is not registered for use in weight management in South Africa. Criteria are: BMI ≥30kg/m2 or BMI ≥27kg/m2 with obesity (adiposity) or a related complication.

» Surgery: Bariatric surgery procedure should be decided by a surgeon in discussion with the patient. options include sleeve gastrectomy, Roux-en-Y gastric bypass or biliopancreatic diversion with/without duodenal switch. Criteria are: BMI ≥40kg/m2 or BMI ≥35-40kg/m2 with an obesity (adiposity) related complication, or BMI ≥30kg/m2 with poorly controlled type 2 diabetes (T2DM).

It is very difficult to maintain dietary interventions and physical activity in the long run without these three major pillars, said Dr Wharton.

Steps 4 and 5: Agree and Assist

Agree on realistic expectations, sustainable behavioural goals, and health outcomes. Agree on a personalised action plan that is practical and sustainable and addresses the drivers of weight gain. Long-term goals have more value than short-term goals, said Dr Wharton.6

Assist in identifying and addressing drivers and barriers. Provide education and resources. Refer to appropriate providers or interdisciplinary teams (if available). Arrange for regular, timely follow up.6

Considerations in the use of pharmacotherapy for obesity

According to Dr Wharton if a patient meets the criteria (BMI ≥30kg/m2 or BMI ≥27kg/m2 with obesity-related comorbidities such as T2DM), pharmacotherapy can be initiated.6

Consider stopping or changing medications associated with elevated weight if possible, comorbidities and specific features. For example, explained Dr Wharton, in diabetes, prediabetes, hypertension, obstructive sleep apnoea, and polycystic ovarian syndrome, glucagon-like peptide-1 receptor agonists are recommended as first-line therapy.6

For cravings, depression and smoking, there is evidence for the naltrexone/ bupropion combination as a first-line agent, liraglutide is the second choice and orlistat the third choice. As mentioned above, combination naltrexone/ bupropion is not registered in South Africa for weight management. In Canada, liraglutide is considered the first choice for diabetes and prediabetes patients, naltrexone/ bupropion is the second choice and orlistat the third choice.6

Assess the patient after three months on the therapeutic dose, based on whether they have been successful in preventing any of the aspects that are concerning, such as diabetes, prediabetes, and cravings. If these things have improved, continue treatment. If there are no or limited improvements, look at adding a second medication or stopping the first medication.6

Box 1: Dietary recommendations

The new Canadian guidelines specifically mention the fact that healthcare practitioners should dispense with the word ‘diet’, which has a lot of negative aspects to it and is associated with a decrease in calories only. The term ‘medical nutrition therapy’ is used in the guidelines. Healthy eating habits appropriate for their medical condition is encouraged. If they have diabetes or prediabetes for instance, this will mean a low-carbohydrate dietary intervention, the Dietary Approaches to Stop Hypertension diet for high blood pressure, the Mediterranean diet for coronary artery disease.6

Box 2: Physical activity recommendations

Physical activity should include 30-60 minutes of moderate to vigorous intensity aerobic physical activity on most days of the week. There is not a significant amount of weight loss, but it leads to better health.6

Aerobic physical activity (30–60 minutes of moderate to vigorous intensity most days of the week) can be considered for adults who want to: 6 » Achieve small amounts of body weight and fat loss » Achieve reduction in abdominal visceral fat and ectopic fat, such as liver and heart fat even in the absence of weight loss » Favour weight maintenance after weight loss » Favour the maintenance of fat-free mass during weight loss » Increase cardiorespiratory fitness and mobility.

Conclusions

Obesity is a growing healthcare concern and is associated with numerous complications that negatively affect the individual, healthcare utilisation and society. A paradigm shift is needed to effectively manage the condition. It should be viewed as a chronic disease that requires changes to the physiology of the affected individual. Calorie restriction should not be the main focus of management but should incorporate a holistic approach that includes lifestyle modification, psychotherapy, pharmacotherapy and surgery.

References available on request. SF