25‐Hydroxyvitamin D deficiency is associated with vascular endothelial dysfunction in middle‐aged and older adults

Abstract

Aging is associated with impaired endothelium‐dependent dilation (EDD) and increased 25‐hydroxyvitamin D (25(OH)D) deficiency. 25(OH)D deficiency is predictive of incident cardiovascular events and mortality. We hypothesized that healthy middle‐aged and older adults (MA/O) who were 25(OH)D insufficient (20–29 ng/mL) or deficient (<20 ng/mL) would demonstrate greater impairment in EDD compared with their 25(OH)D sufficient (>30 ng/mL) peers. Groups did not differ in cardiovascular risk factors or physical activity/fitness. EDD, measured using brachial artery flow‐mediated dilation (FMD), was 25% and 42% lower in insufficient (63±1 yr, n=24, mean±S.E.) and deficient (64±1 yr, n=14) vs. sufficient (60±2 yr, n=8) subjects (3.0±0.3 vs. 3.9±0.3 vs. 5.2±0.5 %, p<0.01), whereas endothelium‐independent dilation (brachial dilation to sublingual nitroglycerine) did not differ among groups (p=0.30). In the overall sample, 25(OH)D was positively related to FMD (r= 0.50; p<0.01) and inversely related to vascular endothelial cell nitrotryosine, a marker of oxidative damage (n=24; r=−0.63; p<0.01). These results indicate that lower circulating 25(OH)D may contribute to oxidative stress‐associated impairment of EDD among healthy MA/O, and suggest vitamin D supplementation may improve EDD in this group.NIH AG013038, AG022241, AG006537, AG0015897, AG03114, AG033994, RR00051