Risk of obstructive sleep apnea in patients with type 2 diabetes mellitus

BACKGROUND AND OBJECTIVES: Type 2 diabetes mellitus (DM) and obstructive sleep apnea (OSA) share several clinical findings: obesity, hypertension, and impaired glucose tolerance. OSA may be an under-recognized comorbidity of DM. The purpose of this study is to estimate the proportion of patients with type 2 DM at risk for OSA and describe factors associated with that risk. METHODS: This cross-sectional study enrolled 297 adults, ages 18 years and older, with type 2 DM from a university-based Fam-ily Medicine Center. Participants completed a research question-naire recording sociodemographic information, medical history, and clinical data including medications and hemoglobin A1C. OSA risk was determined using the Berlin Questionnaire. Relationships be-tween risk of OSA and sociodemographic and clinical variables were evaluated using bivariate analyses and covariate adjusted logistic regression models. RESULTS: Thirty-seven participants (12.5%) had a prior diagnosis of OSA. Based on the Berlin Questionnaire, 124 (48.6%) of the remaining patients were classified as high risk for OSA. Patients less than age 60 years were at increased risk for OSA, adjust-ed OR=2.67 (1.57, 4.54; 95% CI). Non-Hispanic whites, adjusted OR=1.76 (1.01, 3.06; 95% CI), and patients with symptoms of depression, adjusted OR=2.64 (1.60, 4.52; 95% CI), were also at higher risk. Gender and hemoglobin A1C were not associated with increased risk of OSA. CONCLUSIONS: Nearly half of adults with type 2 DM may be at high risk for OSA, and many may be undiagnosed. In a primary care setting, the Berlin Questionnaire is an easily applied screen-ing instrument that identifies patients at increased risk of OSA who may benefit from further diagnostic studies and treatment of OSA.