Theme: Epidemiology & Public Health Research Year: 2024
Background: Opioid dependence is associated with increased risk of suicide. Drug-related mortality among people with opioid dependence in Scotland has more than tripled since 2010, less is known about changes in suicide risk. We aimed to investigate if opiate agonist treatment (OAT) in Scotland is protective against suicide, and to examine trends in suicide risk in those with opioid dependence over time.
Methods: We included individuals in Scotland with at least one prescription for OAT between 2011 and 2020. We calculated standardised mortality ratios (SMR) using the age and sex specific suicide rates in Scotland for years 2011-2020. We fitted multivariable competing-risk regression models to estimate suicide risk by OAT exposure and to estimate trends over time, adjusting for potential confounders.
Results: 46,453 individuals received at least one OAT prescription with over 304,000 person years (py) of follow-up. There were 575 deaths classed as suicide among the cohort and the overall suicide rate was 1·89 (95% CI 1·74-2·05) per 1,000 py. Age and sex SMR for suicide was 7·89 times (7·27-8·56) higher than in the general population.
After adjustment, OAT was shown to be highly protective against suicide, where risk was more than three times greater (adjusted HR: 3·07; 95% CI 2·60-3·62) off OAT compared to on OAT. Suicide risk decreased over time, falling from 2·57 (2·19-3·02) per 1,000 py in 2011-12, to 1·48 (1·21-1·82) in 2019-20.
Conclusion: People with opioid dependence in Scotland are at a greater risk of suicide than the general population. Treatment is protective, with risk of suicide lower among those on OAT. Suicide risk has decreased over time, during a period where drug-related death rates in Scotland have risen to globally high levels. Maintaining and enhancing investment in drug treatment and suicide prevention is essential to sustaining these trends.
Download abstract