1619-P: Risk Factors for Sleep Apnea Syndrome in Nonobese Type 2 Diabetics

Diabetics often have vascular diseases and other comorbidities. Sleep apnea syndrome (SAS) is a disorder characterized by repeated episodes of apnea and hypopnea during nocturnal sleep. Risk factors for SAS include obesity, male gender, and advanced age. It was reported that type 2 diabetes patients (T2DM) without obesity often have SAS. Among the 1,367 ambulant T2DM who were being treated at our institution, 245 (165 men, 80 women) with a BMI <25kg/m2 and who agreed to undergo a portable sleep polygraph test, were evaluated to identify risk factors for SAS, focusing on micro- and macroangiopathy and stable comorbidities. The rates of retinopathy, nephropathy, carotid artery stenosis, coronary artery disease, and peripheral arterial disease were 32.2%, 45.1%, 19.3%, 39.6%, and 15.2%, respectively. The rates of intracranial lesions, respiratory diseases, cardiovascular diseases, cancer, thyroid diseases, and mental illness were 25.7%, 9.4%, 42.4%, 19.2%, 8.6%, and 4.1%, respectively. The apnea-hypopnea index (AHI) was 11.3±9.7 (mean±standard deviation) (12.1±9.9 in men, 9.8±9.1 in women). The prevalence of SAS (AHI≥15) was 25.5% in men and 18.8% in women. Carotid artery stenosis and intracranial lesions were more common among patients with SAS than among those without SAS (p<0.05 each), while no such association was found for microangiopathy. Multivariate analysis adjusting for BMI, male gender, and age identified BMI (odds ratio, 1.23; 95% confidence interval, 1.04-1.47; p<0.05) and intracranial lesions (2.93; 1.51-5.71; p<0.005) as independent risk factors for SAS. The intracranial lesions identified were stable and diverse, ranging from infarction and hemorrhage to benign brain tumor and contusion. The association of intracranial lesions with hypoxia may be related to the respiratory centers, although the underlying mechanism is unknown. T2DM with stable intracranial lesions even without obesity, should be carefully monitored for nocturnal hypoxia, particularly during emergency hospitalization.