Sleep duration and mortality in patients with diabetes: Results from the 2007-2015 Korea national health and nutrition examination survey.

AIM

• To evaluate the association between sleep duration and mortality in adults with type 2 diabetes.

METHODS

• This study was a longitudinal analysis of all-cause mortality according to sleep duration based on the 2007-2015 Korea National Health and Nutrition Examination Survey (KNHANES) linked to the Cause of Death data (ver. 1.1). Adult participants with type 2 diabetes were included in the analysis. According to self-reported sleep duration, participants were divided into five groups (≤ 5 [short sleeper], 6, 7, 8, and ≥ 9 h/day [long sleeper]). All missing values were replaced using multiple imputation. We used Cox proportional hazards models to evaluate the relationship between sleep duration and mortality using age as the time scale.

RESULTS

• Among the final 51,603 participants who were linked to death certificate data, 5,930 (11.5%) had type 2 diabetes. During a median follow-up of 6.5 years, 735 (12.4%) deaths occurred. In multivariable analysis, a J-shaped association between sleep duration and all-cause mortality was observed (P for quadratic trend = 0.003). In particular, long sleep duration was significantly associated with an increased risk of all-cause mortality (adjusted hazard ratio, 1.65; 95% confidence interval, 1.29-2.11. In addition, modifying effects on the relationship between sleep duration and mortality were identified for chronic kidney disease and cancer (P for interaction = 0.003 and 0.002, respectively).

CONCLUSION

• A J-shaped relationship was identified between sleep duration and all-cause mortality in Korean adults with type 2 diabetes. In particular, a long sleep duration was significantly associated with an increased risk of all-cause mortality.