Vascular dysfunction in obstructive sleep apnea and type 2 diabetes mellitus.
Despite the high prevalence of obstructive sleep apnea (OSA) in type 2 diabetes mellitus (DM), the attributable vascular risk from each condition is unknown. We hypothesize that OSA may have a similar effect on vascular function as type 2 diabetes does. Healthy normal-weight subjects, healthy obese subjects, subjects with type 2 diabetes, and obese subjects with OSA were enrolled. Vascular function was assessed with brachial artery ultrasound for flow-mediated dilatation (FMD) and in skin microcirculation by laser Doppler flowmetry. One hundred fifty-three subjects were studied: healthy normal-weight controls (NCs) (n = 14), healthy obese controls (OCs) (n = 33), subjects with DM (n = 68), and obese subjects with OSA (n = 38). The DM group did not undergo sleep study and thus may have had subclinical OSA. The OSA and type 2 diabetes groups had impaired FMD as compared to both the normal-weight and OC groups (5.8 ± 3.8%, 5.4 ± 1.6% vs. 9.1 ± 2.5%, 8.3 ± 5.1%, respectively, P < 0.001, post hoc Fischer test). When referenced to the NC group, a multiple linear regression model adjusting for covariates found that baseline brachial artery diameter (β = -3.75, P < 0.001), OSA (β = -2.45, P = 0.02) and type 2 diabetes status (β = -2.31, P = 0.02), negatively predicted % FMD. OSA status did not seem to affect nitroglycerin-induced vasodilation (endothelium-independent) of the brachial artery or vascular function in the skin microcirculation. OSA impairs endothelial function in the brachial artery to a similar degree as type 2 diabetes does. OSA, however, does not appear to affect brachial endothelium-independent vasodilation or skin microcirculatory function. Treatment of OSA in patients with concomitant type 2 diabetes, therefore, may be a potential therapeutic option to improve macro-, but not microvascular outcomes.
Brigham and Women's Hospital, Boston, Massachusetts, USA.
Susie
S
Yim-Yeh
Shilpa
S
Rahangdale
Anh Tu Duy
AT
Nguyen
Karen E
KE
Stevenson
Victor
V
Novack
Aristidis
A
Veves
Atul
A
Malhotra
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001808:Blood Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology*; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology*; D003925:Diabetic Angiopathies / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D014463:Ultrasonography; D055815:Young Adult