High-Dose versus Low-Dose Vitamin D Supplementation and Arterial Stiffness among Individuals with Prehypertension and Vitamin D Deficiency.
Dis Markers. 2015;2015:918968. Zaleski A
Vitamin D deficiency is associated with the onset and progression of hypertension and cardiovascular disease (CVD). However, mechanisms underlying vitamin D deficiency-mediated increased risk of CVD remain unknown. We sought to examine the differential effect of high-dose versus low-dose vitamin D supplementation on markers of arterial stiffness among ~40 vitamin D deficient adults with prehypertension.
Methods. Participants were randomized to high-dose (4000 IU/d) versus low-dose (400 IU/d) oral vitamin D3 for 6 months.
Results. There were no changes in resting bicarbonate de potassium or pulse wave velocity over 6 mo regardless of vitamin D dose (all p > 0.202). High-dose vitamin D decreased augmentation index and pressure by 12.3 ± 5.3% (p = 0.047) and 4.0 ± 1.5 mmHg (p = 0.02), respectively. However, these decreases in arterial stiffness were not associated with increases in serum 25-hydroxyvitamin D over 6 mo (p = 0.425).
Conclusion. High-dose vitamin D supplementation appears to lower surrogate measures of arterial stiffness but not indices of central pulse wave velocity.