Pharmacy Peer Review: Trends in Opioid Prescribing

Trends in Strong Opioid Prescribing in Ireland

Written by Bridget Norris & Dr Amelia Smith, School of Medicine, Trinity College Dublin

Bridget Norris, School of Medicine, Trinity College Dublin

Opioid analgesics are commonly used to effectively manage acute, terminal and cancer pain. However, there is limited evidence to support their long-term use in chronic non-cancer pain. Opioids are associated with harms such as misuse, addiction and fatal overdose. In addition, the use of opioid analgesics in the elderly can be problematic, due to an increased risk of cognitive issues, falls and fractures. Furthermore, there are concerns that increases in opioid prescribing may lead to increases in the abuse and diversion of opioids. Despite these issues, there has been a well-documented increase in prescription opioid use in many developed countries over the past twenty years, most notably in the United States. Studies in European countries have demonstrated increasing trends in opioid prescribing for chronic non-cancer pain.1,2 A 2019 report by the Organisation for Economic Co-operation and Development (OECD) highlighted that opioidrelated deaths in Ireland are higher than the OECD average, with an increasing trend evident from 2011 to 2016.3 There is a paucity of research on strong opioid prescribing in Ireland. A new study by a team of researchers in Trinity College Dublin and the Health Service Executive’s Medicines Management Programme, published in the journal Pharmacoepidemiology and Drug Safety (doi:10.1002/pds.5247), has examined recent trends in strong opioid prescribing in Ireland.4 The researchers carried out a repeated cross-sectional analysis of the Health Service Executive-Primary Care & Reimbursement Service (HSE-PCRS) pharmacy claims database between 2010 and 2019 to identify adults, aged 16 years and over that were prescribed a strong opioid, under the General Medical Services (GMS) scheme. The researchers categorised opioids as ‘strong’ in accordance with the British National Formulary classification.5 The following strong opioids were included in the study: morphine, morphine combinations, hydromorphone, buprenorphine, fentanyl, oxycodone, oxycodone and naloxone, pethidine, tapentadol, tramadol, tramadol and paracetamol and tramadol and dexketoprofen. The analysis was conducted in terms of prescribing prevalence (number of individuals receiving a strong opioid prescription in the year x 100/number of GMS eligible individuals for that year). In addition, defined daily dose (DDD) per 1,000 population per day was calculated for each study year, as this metric takes dose and treatment duration into account. The data was stratified by route of administration, age (16-64 years and ≥65 years) and

Dr Amelia Smith, School of Medicine, Trinity College Dublin gender. The number of GMS eligible patients aged 16 years and over during each year of the study period ranged from 1,219,749 to 1,421,795.

Key Findings

• The prescribing prevalence of strong opioids increased over the study period from 14.43% in 2010 to 16.28% in 2019, with the greatest increase in the ≥65 years age group. • Overall, the prescribing prevalence of strong opioids in the GMS population aged ≥65 years was twice that in the population aged 16-64 years; it increased from 20.3% in 2010 to 23.48% in 2019.

• The prescribing prevalence of strong opioids in the female

GMS population was 1.3 times that of the male GMS population. • Non-combination oxycodone demonstrated a 2.1-fold increase in prescribing prevalence over the study period, while oxycodone and naloxone increased 5.2-fold between 2011 and 2019.

• The prescribing prevalence and

DDD per 1,000 population per day of tapentadol increased 8.8fold and 9.9-fold, respectively between 2012 and 2019.

• Tramadol was the most commonly prescribed, accounting for 63.9% of total strong opioid prescribing.

There was a decrease in the prescribing prevalence of tramadol over the ten-year period, from 10.80% to 8.47%. • The use of transdermal strong opioid formulations increased markedly over the ten-year period. The Medicines Management Programme aims to provide sustained national leadership relating to safe, effective, and cost-effective prescribing in Ireland, in collaboration with the National Medicines Information Centre (NMIC), the National Centre for Pharmacoeconomics (NCPE), and the HSE-Primary Care Reimbursement Service (HSEPCRS).The researchers noted that it is possible that the increase in opioid prescribing observed was in part associated with inappropriate prescribing. Further studies to investigate potentially inappropriate prescribing should be conducted, given the harms associated with opioid analgesics and the uncertainly regarding their benefits in chronic noncancer pain. It is important that strong opioids are initially trialled for a short duration of time, at low doses and treatment ceased if not found to be beneficial. In addition, consideration should be given to the addition of nonpharmacological pain relief options and/or non-opioid analgesics, to reduce the overall opioid burden. The researchers concluded that there was an overall increase in the prescribing of strong opioids in Ireland between 2010 and 2019, particularly in older adults. Tramadol was the most frequently prescribed strong opioid to GMS patients over the study period, while oxycodone and tapentadol prescribing increased markedly in all demographic groups. Continued surveillance of oxycodone, tapendatol and tramadol prescribing in Ireland is warranted.

References

1. Zin CS, Chen LC, Knaggs RD. Changes in trends and pattern of strong opioid prescribing in primary care. Eur J Pain. 2014;18(9):1343-1351. 2. Chenaf C, Kabore JL, Delorme J, et al. Prescription opioid analgesic use in France: Trends and impact on morbidity-mortality. Eur J Pain. 2019;23(1):124-134. 3. Organisation for Economic Co-operation and Development. Urgent action needed to address growing opioid crisis. https://www. oecd.org/health/urgent-actionneeded-to-address-growingopioid-crisis.htm. Published 2019. 4. Norris BA, Smith A, Doran S, Barry M. Trends in strong opioid prescribing in Ireland: A repeated cross-sectional analysis of a national pharmacy claims database between 2010 and 2019. Pharmacoepidemiol Drug Saf. doi:10.1002/pds.5247 5. Joint Formulary Committee. British national formulary 78. London: British Medical Association and Royal Pharmaceutical Society of Great Britain; 2020.