Impact of changes in controlled drugs legislation on benzodiazepine receptor agonist prescribing in Ireland: a repeated cross-sectional study

PURPOSE: To examine the impact of new controlled drugs legislation introduced in May 2017 on benzodiazepine receptor agonist (BZRA) prescribing in Ireland. METHODS: A repeated cross-sectional analysis was conducted using publically available monthly pharmacy claims data from the General Medical Services (GMS) database. The study population comprised all GMS-eligible individuals aged ≥ 16 years from January 2016 to September 2019. Monthly prevalence rates of individuals receiving BZRA prescriptions per 10,000 eligible population were calculated and trends examined over time. Segmented linear regression of prevalence rates was used to examine changes before and after introduction of the legislation stratified by gender and age groups. Regression coefficients (β) and 95% confidence intervals (CIs) for monthly change were calculated. RESULTS: Pre-legislation (January 2016 to April 2017), there was a significant monthly decline in benzodiazepine prevalence rate (β = − 1.18; 95% CI − 1.84, − 0.51; p < 0.001) but no significant change in Z-drug prescribing. Post-legislation (May 2017 to September 2019), increases in prevalence rates were observed for benzodiazepines (β = 1.04; 95% CI 0.17, 1.92; p = 0.021) and Z-drugs (β = 1.04; 95% CI 0.26, 1.83; p = 0.010). Post-legislation trends showed increases in BZRA prevalence rates among the youngest subgroup (16–44 years), with variable changes in the middle-aged subgroup (45–64 years) and no changes in the oldest subgroup (≥ 65 years). CONCLUSIONS: This study indicates that introduction of new legislation had limited impact on BZRA prescribing on the main public health scheme in Ireland. Interventions targeting specific population subgroups may be required to achieve sustained reductions in prescribing. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00228-020-03063-z.