Serum 25-hydroxyvitamin D deficiency and insufficiency are associated with Ankle-Brachial Index but not arterial stiffness in an elderly community-dwelling Chinese population

Vitamin D deficiency may increase arterial stiffness, a sub-clinical symptom of Target Organ Damage (TOD). This study aimed to investigate the associations between total serum vitamin D level and arterial stiffness assessed by brachial-ankle Pulse Wave Velocity (baPWV) and atherosclerosis assessed by Ankle-Brachial Index (ABI) in a Chinese community-dwelling elderly cohort. About 175 elderly participants (91 males and 84 females) were recruited. The levels of total serum 25-hydroxyvitamin D [25(OH)D], blood glucose, lipids and pressure were determined with clinical tests. We found 87.4% of elderly Chinese showed vitamin D deficiency (<20 ng/mL) and insufficiency (21-29 ng/mL). For these patients, the total 25(OH)D was positively correlated with right (r = 0.230, p = 0.004) and left ABI (r = 0.212, p = 0.008), whereas there was no correlation with right and left baPWV (r = -0.136 and -0.137, p = 0.092 and 0.089, respectively). In univariate linear regression, total serum 25(OH)D was positively associated with left and right ABI (p < 0.05). Multivariate regression suggested total serum 25(OH)D was independently correlated with the left and right ABI with adjustment for sex, age and Diastolic Blood Pressure (DBP). No significant association between total serum 25(OH)D level and baPWV was found. The study suggested that serum total 25(OH)D may be favorably associated with ABI in the elderly population with vitamin D deficiency and insufficiency; however, it may not correlated with arterial stiffness measured by baPWV. More prospective larger scale studies are warranted to validate these findings.