NEW YORK (Reuters Health) – Low serum levels of 25-hydroxyvitamin D (25(OH)D) are associated with an increased prevalence of peripheral arterial disease (PAD), according to a report in the June issue of Arteriosclerosis, Thrombosis, and Vascular Biology.

“Vitamin D may have important roles outside of calcium and phosphate metabolism and osteoporosis,” Dr. Michal L. Melamed from Albert Einstein College of Medicine, Bronx, New York told Reuters Health.

Dr. Melamed and colleagues evaluated the association between serum 25(OH)D levels and the prevalence of PAD in the general population using data from the National Health and Nutrition Examination Survey (NHANES).

Mean serum 25(OH)D levels were significantly lower in subjects with PAD than in those without PAD, the authors report, but the two groups did not differ in serum calcium, phosphate, or parathyroid hormone levels.

Participants in the lowest 25(OH)D quartile were 2.18 times more likely to have PAD than were participants in the highest 25(OH)D quartile after adjustment for age, gender, and race.

Each 10 ng/mL decrease in serum 25(OH)D was associated with a 35% increase in the prevalence of PAD, the investigators say.

“Several mechanisms have been invoked in the literature to support a potential anti-atherosclerotic activity of vitamin D,” the researchers note.

Dr. Melamed cautions, however, that “the evidence is not quite there yet to suggest patients with PAD would benefit from vitamin D supplementation.” She added, “If there is a causal relationship between low vitamin D levels and PAD, it may be that long-standing vitamin D deficiency causes PAD and that intervening once PAD is already established may not change the course of the disease. Therefore, more studies are needed in this area.”

Arterioscler Thromb Vasc Biol 2008;28:1179-1185.