Relationships between sleep apnea, cardiovascular disease risk factors, and aortic pulse wave velocity over 18 years: the Wisconsin Sleep Cohort.

PURPOSE

The purpose of this study is to determine if apnea-hypopnea index (AHI) severity predicts future aortic pulse wave velocity (PWV) in the Wisconsin Sleep Cohort.

METHODS

Applanation tonometry was used to derive carotid-to-femoral PWV a mean of 18 years (standard deviation 4) after overnight polysomnography. Multivariable regression models were created to describe prospective associations between baseline AHI and future PWV.

RESULTS

The 618 adults were mean 65 (7) years old (55 % male) with a mean body mass index of 31 (7) kg/m(2) at the tonometry visit. Mean baseline AHI was 4.6 (9.7) events/h. In multiple linear regression models adjusted for age (β = 0.13/year, standard error [SE] = 0.01, p < 0.001) and sex, higher log10AHI (β = 0.43/events/h, SE = 0.18, p = 0.02) was associated with PWV. After adjustment for waist circumference (β = 0.01/cm, SE = 0.01, p = 0.05) and height, the association between baseline log10AHI and future PWV was not statistically significant (p = 0.11), although the association with age persisted unchanged. Addition of covariates such as smoking status (current smoker β = 0.66, SE = 0.22, p = 0.002), diabetes mellitus status (β = 2.89, SE = 0.59, p < 0.001), and systolic blood pressure (BP, β = 0.03/mmHg, SE = 0.01, p < 0.001) did not change the association. AHI did not interact with age or smoking status to predict PWV. A secondary analysis of nocturnal oxygen saturation parameters in 517 participants, 9 (2) years prior also did not show any significant relationships with future PWV.

CONCLUSIONS

The prospective association between AHI and PWV is confounded by body size and influenced by smoking, diabetes mellitus, and BP. Weight management, BP control, and smoking cessation may help prevent arterial stiffening associated with obstructive sleep apnea.