Self-reported sleep disturbances and prostate cancer morbidity and mortality in Swedish men: A longitudinal study over 40 years

The present study, with an observational period of about 40 years, examined the association between self-reported sleep disturbances (i.e. problems with falling and staying asleep; use of hypnotics) and prostate cancer morbidity and mortality in initially 2322 men (all 50 years old at baseline). Self-reported sleep disturbances and established risk factors (e.g. age, lower urinary tract symptoms, smoking and family history of cancer) were measured at ages 50 and 70 years. Information about prostate cancer diagnosis and deaths as a result of prostate cancer was available from the National Cancer Registry and the Swedish Civil Registry of Morbidity. During the observational period, 263 participants developed prostate cancer (11% of the total cohort); 146 of them died as a result of prostate cancer. There was no association between sleep disturbances and prostate cancer morbidity or mortality (hazard ratio 1.09, 95% confidence interval (CI) 0.79, 1.52, and hazard ratio 1.21, 95% CI 0.77, 1.91, respectively). Similar findings were observed when examining associations between single sleep disturbance parameters and prostate cancer morbidity and mortality. Our study does not provide evidence that reports of sleep disturbances increase the risk of prostate cancer morbidity or mortality in middle to older-aged men. Therefore, assessing subjective sleep problems may not meaningfully help to identify men at risk of developing prostate cancer or dying of this devastating condition.