Polysomnographic phenotypes of obstructive sleep apnea and incident type 2 diabetes results from the dream study

Abstract

Rationale: Obstructive sleep apnea (OSA) is associated with cardiovascular disease and incident type 2 diabetes (T2DM). Seven OSA phenotypes, labeled on the basis of their most distinguishing polysomnographic features, have been shown to be differentially associated with incident cardiovascular disease. However, little is known about the relevance of polysomnographic phenotypes for the risk of T2DM. Objectives: To assess whether polysomnographic phenotypes are associated with incident T2DM and to compare the predictive value of baseline polysomnographic phenotypes with the Apnea-Hypopnea Index (AHI) for T2DM. Methods: The study included 840 individuals without baseline diabetes from amultisite observationalU.S. veteran cohort who underwentOSA evaluation between 2000 and 2004, with follow-up through 2012. The primary outcomewas incident T2DM, defined as no diagnosis at baseline and a newphysician diagnosis confirmed by fasting blood glucose.126mg/dL during follow-up. Relationships between the seven polysomnographic phenotypes (1.mild, 2. periodic limbmovements of sleep [PLMS], 3. non-rapid eye movement and poor sleep, 4. rapid eye movement and hypoxia, 5. hypopnea and hypoxia, 6. arousal and poor sleep, and 7. combined severe) and incident T2DMwere investigated using Cox proportional hazards regression and competing risk regression models with andwithout adjustment for baseline covariates. Likelihood ratio testswere conducted to compare the predictive value of the phenotypeswith theAHI. Results: During a median follow-up period of 61 months, 122 (14.5%) patients developed incident T2DM. After adjustment for baseline sociodemographics, fasting blood glucose, body mass index, comorbidities, and behavioral risk factors, hazard ratios among persons with "hypopnea and hypoxia"and "PLMS"phenotypes as compared with persons with "mild"phenotype were 3.18 (95% confidence interval [CI], 1.53-6.61] and 2.26 (95% CI, 1.06-4.83) for incident T2DM, respectively. Mild OSA (5