Association between Self-reported Snoring and Prediabetes among Adults Aged 40 Years and Older without Diabetes.

Background: Several previous studies have shown that snoring is associated with glucose metabolism and the development of diabetes, but rare study has shown the association between snoring frequency and prediabetes, particularly in China. We hypothesized that individuals who snore might have a higher risk of prediabetes. This study aimed to investigate the association between self-reported snoring and prediabetes in a Chinese population. Methods: A cross-sectional study was performed in three large communities of Beijing from December 2011 to August 2012 by recruiting individuals aged > 40 years old. All participants were requested to complete a detailed questionnaire and undergo anthropometric measurements. A 75 g oral glucose tolerance test was performed in individuals without diabetes. Blood samples of all participants were collected; blood glucose and blood fat levels were measured. Multivariate logistic regression models were built to assess the association between snoring frequency and prediabetes. Results: A total of 13,592 participants (female: 66.56%; mean age: 56.8 +/- 7.9 years; mean body mass index: 25.5 +/- 3.4 kg/m(2)) were included in the final analysis. Of these, 30.9% were diagnosed with prediabetes, while 41.3% and 25.4% had occasional and habitual snoring, respectively. Habitual snoring was associated with an increased risk of prediabetes (odds ratio [OR]: 1.3, 95% confidence interval [C]: 1.1-1.4, P< 0.00 1), after adjusting for diabetes and sleep-related confounders in the multivariable models. Habitual snoring was also associated with isolated impaired fasting glucose (IFG; OR: 1.3, 95% CI: 1.0-1.6; P < 0.001) and isolated impaired glucose tolerance (IGT; OR: 1.3, 95% CI: 1.2-1.5; P < 0.001), but not IFG + IGT (OR: 1.1, 95% CI: 0.9-1.4; P= 0.281). When stratified by total cholesterol (TC) levels, this association between habitual snoring and prediabetes was observed only in individuals with TC < 5.6 mmol/L (OR: 1.4, 95% CI: 1.2-1.6; P< 0.001). Conclusions: Habitual snoring is associated with prediabetes, but only in individuals with TC < 5.6 mmol! L. Further prospective studies are needed to confirm this finding.