Association of Diabetic Microvascular Complications and Parameters of Obstructive Sleep Apnea in Patients with Type 2 Diabetes.

Abstract

Obstructive sleep apnea (OSA) is prevalent in patients with type 2 diabetes, but the influence of OSA on diabetes complications is not clear. We aimed to investigate the association of OSA with chronic diabetes complications in Chinese patients with type 2 diabetes. In total, 880 hospitalized patients were enrolled in a multicenter, cross-sectional study that involved 12 hospitals from six cities in the People's Republic of China. Overnight sleep monitoring with a portable monitor was used to record respiratory parameters, including the apnea-hypopnea index (AHI), the oxygen desaturation index (ODI), the oxygen saturation (SPO2), and the cumulative time of SPO2 below 90% or 85% (CT90% and CT85%, respectively). Chronic diabetes complications were recorded from medical charts. CT90% was independently associated with diabetic nephropathy (DN) after adjusting for age, sex, diabetes duration, glycosylated hemoglobin, body mass index, hypertension, and the use of angiotensin converting enzyme inhibitor/angiotensin receptor blocker drugs within 1 week. The associated parameters increased from two (the average SPO2 and CT90%) to three (ODI, the lowest SPO2, and CT85%) when the severity of DN increased from microalbuminuria to renal insufficiency. The estimated glomerular filtration rate was independently correlated with ODI (β = -0.172, P = 0.029) and the lowest SPO2 (β = 0.354, P = 0.004) after adjustments. The lowest SPO2 was associated with proliferative diabetic retinopathy by univariate logistic regression but was not significant in multivariate regression after adjustment. Parameters of nocturnal hypoxemia are associated with DN and renal function of patients with type 2 diabetes. The parameters of hypoxemia may more sensitively reflect the association of OSA and diabetic microvascular complications than AHI.