Socio‐economic differences in the effectiveness of pharmacotherapy use in alcohol use disorder: A cohort study of 148 626 individuals in Sweden

Aim To examine the socioeconomic differences in the effectiveness of alcohol use disorders (AUD) pharmacotherapy and risk of AUD hospitalisation. Design A prospective register‐based cohort study. Setting Sweden. Participants Individuals who were registered as living in Sweden in 2005 (16–64 years) with a first‐time AUD diagnosis and complete information on their socioeconomic position (SEP) between 2005 and 2019 ( n = 148 626). Measurement The outcome was AUD hospitalisation. The use of AUD pharmacotherapy was treated as a time‐varying exposure. SEP was the moderator. The association between the joint‐exposure (pharmacotherapy use and SEP) and AUD hospitalisation was assessed using a competing‐risk regression model, adjusted for sociodemographic factors, previous mental health diagnoses and use of other psychiatric medications. Findings Pharmacotherapy use was associated with a lower risk of AUD hospitalisation among high SEP individuals [subdistribution hazard ratio (SHR) = 0.83, 95% confidence interval (CI) = 0.77–0.90], but not among those with low SEP (SHR = 1.02, 95% CI = 0.94–1.10) and middle SEP (SHR = 1.01, 95% CI = 0.94–1.09), compared with low SEP individuals when not using pharmacotherapy. Conclusions In Sweden, alcohol use disorder (AUD) pharmacotherapy appears to be effective to reduce the risk of AUD hospitalisation only among individuals of high socioeconomic position.