Sleep duration is a potential risk factor for newly diagnosed type 2 diabetes mellitus.

U-shaped patterns have been observed for the relationship between sleep duration and diabetes. In addition, prediabetes is associated with the risk of cardiovascular diseases and diabetes. However, there are few studies investigating the relationship between sleep duration and prediabetes/newly diagnosed diabetes. The aim of this study is to examine the relationship between sleep duration and prediabetes/newly diagnosed diabetes in a Taiwanese population. After excluding the subjects with a high risk of obstructive sleep apnea, those with a positive history of diabetes, or those taking hypnotic drugs, a total of 3470 adults were recruited from a health checkup center. Each subject completed a self-administrated structured questionnaire on sleep duration and lifestyle factors. Prediabetes/diabetes was defined following the definition of the American Diabetes Association. Subjects with different sleep durations were classified into short (<6.0 hours), normal (6.0∼8.49 hours), and long sleepers (≥8.5 hours). The proportion of subjects with normal glucose tolerance, prediabetes, and newly diagnosed diabetes was 71.9%, 22.9%, and 5.2%, respectively. There were significant differences in age, sex, weight, education level, body mass index, waist-to-hip ratio, systolic and diastolic blood pressure, alcohol and coffee drinking habits, family history of diabetes, and sleep duration among the 3 glycemic groups. In multinomial regression, both short and long sleepers had a higher risk of newly diagnosed diabetes; and the odds ratio were 1.55 (95% confidence interval, 1.07-2.24) and 2.83 (1.19-6.73), respectively. However, sleep duration was not found to relate to prediabetes. In conclusion, both short and long sleep durations were independently associated with newly diagnosed diabetes, but not with prediabetes.