The epidemiology of regular opioid use and its association with mortality: Prospective cohort study of 466 486 UK biobank participants

BACKGROUND: Opioids have, at most, small benefits for non-cancer pain in the medium and long-term but there is good evidence that they cause harm. The current study describes the characteristics and clinical status of people taking regular opioids in Great Britain and determines whether use is associated with mortality risk. METHODS: An analysis of participants in UK Biobank, a prospective population-based study. At recruitment (2006–10) participants reported medicines which they regularly used in addition to lifestyle and health-related factors. Information was available on deaths until October 2016. FINDINGS: There were 466 486 participants (54% women) aged 40–69 years and without a prior history of cancer of whom 5.5% were regularly using opioids. Use increased with age-group, was more common in females (6.3% v. 4.6%) and 87% of persons using them reported chronic pain. The highest rates of use (~1 in 9) were in people with low household income, who left school <16 years and lived in areas with high deprivation. Amongst 15,032 people who could not work because of ill-health, 1 in 3 were regularly taking opioids. Regular users reported insomnia (88.7%), a recent major recent life event (57.3%) and were much more likely than non-users to rate their health as poor (RR 5.5, 99% CI (4.9, 6.1)). Those taking weak (4.2% of participants) or strong (1.4%) opioids were more likely to die during follow-up (6.9% and 9.1% respectively v. 3.3% in non-users) an excess which remained after adjustment for demographic, socio-economic, health and lifestyle factors (MRR 1.18 99% CI (1.06, 1.32) and 1.20 99% CI (1.01, 1.43)) respectively. INTERPRETATION: Regular use of opioids is common in Great Britain, particularly in groups of low socio-economic status. Most users still report chronic pain, poor health generally and are at increased risk of premature death although it is not established that this relationship is causal. FUNDING: There were no external sources of funding obtained for the current analyses.