Predictors of sleep disturbance in heroin users receiving methadone maintenance therapy: a naturalistic study in Taiwan

INTRODUCTION: Sleep disturbance is a major health concern for heroin users receiving methadone maintenance treatment (MMT). The present study was aimed to investigate the predictors for new-onset clinically predominant sleep disturbance (CPSD) among heroin users receiving MMT. METHODS: This 2-year retrospective study included 152 individuals (127 males and 25 females) with heroin use disorder who visited our MMT clinics for the first time. A univariate Cox proportional hazards regression model (Cox model) was used to estimate the potential factors of subsequent CPSD, followed by a multivariate Cox model to identify significant predictors of CPSD after adjusting for other covariates. RESULTS: Twenty-nine (19.1%) participants developed CPSD during the 2-year period. After forward selection in the Cox model, earlier age at onset of heroin exposure (OR=0.95; P=0.044), lower attendance rate (OR =0.04; P=0.03), greater maximum dose of methadone (OR =1.01; P=0.022), and shorter time to maximum methadone dose (OR =0.98; P=0.007) were significantly associated with new-onset CPSD. CONCLUSION: We identified predictors that were significantly associated with new-onset CPSD, and clinicians should be aware of sleep disturbance in heroin users receiving MMT with these risk factors. Future studies are necessary to verify our findings and extend the applicability.