Sleep-related problems and minor psychiatric disorders among Brazilian shift workers

The aim of this study was to explore the association between sleep-related problems with the occurrence of minor psychiatric disorders in shift workers of southern Brazil. A cross-sectional study with 1202 workers (785 females) aged 18–50 years was carried out. Minor psychiatric disorders were assessed using the Self-Reporting Questionnaire (SRQ-20), and four sleep problems were collected and analyzed: sleep deprivation (≤ 5h), difficulty falling asleep, waking up during sleep, and sleep medication use. Results show that the overall prevalence of minor psychiatric disorders was 26.8%, but it was more prevalent among females than males (30.2% vs. 20.4%). Nightshift work was significantly associated with the occurrence of sleep-related problems. After adjusting for confounding factors, the number of sleep-related problems showed a positive linear trend with psychiatric disorders in both sexes. Having two or more sleep-related problems was associated with increased probability of psychiatric disorders approximately three-fold among males and two-fold among females, when compared with those without sleep problems. In conclusion, this study demonstrated that sleep-related problems have a strong and independent association with psychiatric disorders among shift workers. Furthermore, the prevalence of both conditions was higher among females than males; however, the strength of these associations was higher in males. •The extent of the mental health problems in shift workers is largely unknown.•This study included a large occupational sample of shift workers from Brazil.•A strong association between sleep problems and psychiatric disorders was observed.•Have two or more sleep problems increased the occurrence of psychiatric disorders.•Psychiatric disorders and sleep problems were more prevalent among females.