Social and structural determinants of health associated with drug use patterns among female sex workers in Iran: A latent class analysis.

ABSTRACT

BACKGROUND: Female sex workers (FSWs) experience adversities regarding social determinants of health (SDH) and behavioural factors including illicit drug use. This study aimed to assess the clustered impact of SDH on illicit drug use among FSWs in Iran. METHODS: We surveyed 1,347 FSWs in 13 major cities in 2015. Latent class analysis was conducted to identify distinct classes of five measured SDH including low education, unemployment, unstable housing, last-year incarceration and sexual violence. We examined the association of these classes with five illicit drug use patterns using multivariable generalized linear model with Poisson family and log link, and reported adjusted prevalence ratios (aPR) and their 95% confidence intervals (CI). RESULTS: We identified five SDH classes Class 1 no SDH adversities; Class 2 mainly unemployment; Class 3 low education and unemployment; Class 4 sexual violence and unemployment; and Class 5 multiple SDH adversities. The prevalence of last-month drug use ranged from 7.0% in Class 1 to 53.3% in Class 5. Compared to FSWs in Class 1, those in Class 2 (aPR 2.47, 95% CI 1.15, 5.27), Class 3 (aPR 3.69, 95% CI 1.62, 8.36), Class 4 (aPR 4.49, 95% CI 1.71, 11.78) and Class 5 (aPR 6.35, 95% CI 2.42, 16.69) were more likely to report last-month drug use. The same patterns were observed for specific drugs of opium use, crystal methamphetamine use, and heroin-crack use, as well as poly-drug use. CONCLUSION: Socio-structural determinants are clustered together and elevate the likelihood of illicit drug use among FSWs. Our findings highlighted the significance of assessing and addressing such key determinants of health in drug use harm reduction programs targeting FSWs.