Prevalence and determinants of opioid use disorder among long-term opiate users in Golestan Cohort Study

Abstract

Abstract Background Number of opiate users worldwide has doubled over the past decade, but not all of them are diagnosed with opioid use disorder (OUD). We aimed to identify the prevalence and risk factors for OUD after ten years of follow-up. Methods Among 8,500 chronic opiate users at Golestan Cohort Study baseline (2004–2008), we recalled a random sample of 451 subjects in 2017. We used three questionnaires: a questionnaire about current opiate use including type and route of use, the drug use disorder section of the Composite International Diagnostic Interview lifetime version, and the validated the Kessler 10 (K10) questionnaire. We defined OUD presence and severity based on the DSM-5 criteria and used a cutoff of 12 on K10 questionnaire to define psychological distress. Results Mean age was 61.2 ± 6.6 years (84.7% males) and 58% were diagnosed with OUD. Starting opiate use at an early age and living in underprivileged conditions were risk factors of OUD. Individuals with OUD were twice likely to have psychological distress (OR = 2.25; 95%CI: 1.44–3.52) than the users without OUD. In multivariate regression, former and current opiate dose and oral use of opiates were independently associated with OUD. Each ten gram per week increase in opiate dose during the study period almost tripled the odds of OUD (OR = 3.18; 95%CI: 1.79–5.63). Conclusions Chronic opiate use led to clinical OUD in more than half of the users, and OUD was associated with psychological distress, increasing its physical and mental burden in high-risk groups.