Use and misuse of sedative drugs and related substances - Findings in the general population and in individuals with opioid dependence

Sammanfattning: Background: Prescription sedatives are efficient in the treatment of anxiety and sleeping disorders, but are associated with a risk of misuse and dependence, as well as an increased risk of accidents, injuries and overdoses, both in the general population and especially in individuals with other substance misuse. The present thesis aims to investigate prescription sedative use and misuse in two kinds of samples - in the general population, with focus on its association with subjective health and quality life, and in the subpopulation of individuals with opioid dependence, with focus on treatment outcome in opioid maintenance treatment and mortality. Materials and Methods: Prescription sedative misuse was studied in three Swedish datasets: 1) a general population survey (n =22,095), 2) a clinical pilot study for the treatment of opioid dependence (n =44 and 36, for the original study and the follow-up study, respectively), and 3) a national register-based study of individuals in opioid maintenance treatment ( n= 4,501). Results: In the general population, sedative misuse was found to be associated with poor self-assessed mental health and poor quality of life. In individuals with opioid dependence, benzodiazepine misuse was found to be negatively associated with retention in opioid maintenance treatment. Prescription of sedatives was associated with mortality in individuals with opioid dependence, including associations between prescriptions of ‘z-drug’ hypnotics and pregabalin and overdose death. Conclusions: It is important to be aware of the associations with mental health problems and quality of life in individuals with sedative misuse. In individuals with opioid dependence, clinicians also need to be aware of the increased risk of overdose and non-overdose death, as well as possible negative effects on treatment outcome, that come with sedative use and misuse.