Sleep quality and risk of diabetes and coronary artery disease among young men.

AIMS: To assess the time-dependent effect of sleep quality on diabetes and coronary artery disease (CAD) incidence among young adults.

METHODS: Incident rates of diabetes and CAD during a mean follow-up of 6.4 ± 4.1 years were assessed among 26,023 men (mean age 30.9 ± 5.6 years) of the Metabolic Lifestyle and Nutrition Assessment in Young Adults stratified by sleep quality at baseline, as assessed by the Mini-Sleep Questionnaire (MSQ). Incident diabetes and CAD were analyzed using a Cox proportional hazard model.

RESULTS: There were 445 cases of diabetes and 92 cases of CAD during 151,312 person-years. An abnormal MSQ score was associated with a 53 % higher incidence of diabetes (95 % CI 1.22-1.94, p < 0.001) compared to those with a normal score, after adjustment for clinical and biochemical diabetes risk factors. The increased risk associated with abnormal sleep quality remained when MSQ was modeled as a continuous time-dependent variable in a multivariable model (HR = 1.036, 95 % CI 1.024-1.049, p < 0.001). The increased risk was higher among overweight or obese participants (BMI and MSQ interaction p = 0.046). Sustained abnormality in MSQ score resulted in higher HR for diabetes (2.35; 95 % CI 1.564-3.519, p < 0.001). In addition, abnormal sleep quality was associated with a 2.38 higher incidence of CAD (95 % CI 1.38-4.11, p = 0.002), after adjustment for traditional clinical and biochemical risk factors.

CONCLUSIONS: Sleep quality contributes to the development of diabetes and CAD in apparently healthy young adults in a time-dependent manner. The use of a simple questionnaire to assess sleep quality may be a useful tool for risk stratification in this population.