Sleep disorders associated with risk of prostate cancer: a population-based cohort study

BACKGROUND: Disrupted sleep rhythms may lead to cancer development. We conducted a population-based cohort study to evaluate the incidence and risk of prostate cancer in patients with sleep disorders (SDs). METHODS: Patients newly diagnosed with SDs between 2000 and 2010 were enrolled from the Taiwan Longitudinal Health Insurance Database. A non-SD cohort age-matched (5-y intervals), comorbidities, and medications was randomly sampled from the general population at a 1:1 ratio. The follow-up period extended from the index date of SDs to the diagnosis of prostate cancer, censoring, or the end of 2013. We used Cox proportional hazards models to calculate the risk of prostate cancer. RESULTS: In total, 41,444 patients were enrolled in each cohort. The mean age of the SD cohort was 48.0 years and that of the non-SD cohort was 47.8 years, with 58.2% of both cohorts aged younger than 50 years. The incidence of prostate cancer increased with age. The overall incidence of prostate cancer was higher in the SD cohort than in the non-SD cohort (9.56 vs 6.36 per 10,000 person-y), with an adjusted hazard ratio of 1.42 (95% CI = 1.20–1.69). Age-specific analysis revealed a 1.35-fold increased risk of prostate cancer in the patients aged ≥65 years in the SD cohort compared with the non-SD counterparts (95% CI = 1.10–1.65). CONCLUSIONS: Patients with SDs are associated with increased risk of prostate cancer.