Prevalence of type 2 diabetes in patients with obstructive sleep apnea in a multi-ethnic sample

Abstract

Study Objectives: Relationship of obstructive sleep apnea (OSA) with insulin resistance and type 2 diabetes in Caucasians has been studied, but this association has not been investigated in Hispanic and African-Americans. The objective of this study is to determine the prevalence of type 2 diabetes in patients evaluated for OSA in a predominantly African American and Hispanic sample. The secondary objective is to evaluate the relationship of REM related OSA and type 2 diabetes. Methods: 1008 consecutive patients who had a comprehensive polysomnography were evaluated. OSA was defined as an obstructive apnea-hypopnea index (AHI) of ≥ 5 per hour. REM AHI of ≥ 10 was considered to indicate REM related OSA. Results: The prevalence of type 2 diabetes was 30.1% in the group with OSA compared to 18.6% in those without OSA. The subjects with OSA had significantly increased odds of type 2 diabetes compared with those without OSA (odds ratio = 1.8, 95% confidence interval: 1.3-2.6) but this association became non-significant when controlled for confounding variables and covariates (odds ratio = 1.3, 95% confidence interval: 0.9-2.0). Middle-aged participants with OSA had 2.8 times higher odds for type 2 diabetes, when compared to younger or middle aged without OSA, controlling for covariates. Finally, the odds of type 2 diabetes were 2.0 times higher in patients with REM AHI of ≥ 10/h independent of confounding variables. Conclusions: OSA is not independently associated with type 2 diabetes in a predominantly African American and Hispanic sample. However, the relationship of REM related OSA with type 2 diabetes may be statistically significant.