July 24, 2008 — Low levels of vitamin D appear to be an independent predictor of fatal stroke — a finding that suggests supplementation may be a promising approach for stroke prevention.
Investigators at the University of Heidelberg, in Germany, found that among individuals referred for coronary angiography, low levels of 25-hydroxyvitamin D were more likely to suffer fatal stroke even after adjusting for cardiovascular risk factors, physical activity level, and calcium and parathyroid hormone levels.
"Vitamin D supplementation in stroke patients has already been shown to reduce osteopenia, fractures, and falls while improving muscle strength. Apart from these beneficial effects, our results suggest that vitamin D might also directly protect against stroke," the authors write.
Published online July 17 in Stroke, with first author Stefan Pilz, MD, these latest results from the Ludwigshafen Risk and Cardiovascular Health (LURIC) study follow a paper from the same cohort published June 23 in Archives of Internal Medicine that showed a link between low levels of vitamin D and both cardiovascular death and all-cause mortality (Dobnig H et al. Arch Intern Med. 2008;168:1340-1349).
The study included 3316 patients referred for coronary angiography. Serum levels of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were measured in 3299 and 3315 subjects, respectively.
After a median follow-up time of 7.75 years, 769 patients died, including 42 from fatal strokes. Of these, 27 were ischemic, 8 hemorrhagic, and 7 of unknown etiology.
Low levels of vitamin D are considered 1 of the most common medical conditions worldwide; it is estimated that more than 50% of children and adults in the United States and Europe are at risk.
Commonly known as the "sunshine vitamin," vitamin D's critical role in bone health is widely recognized. However, an abundance of recent research linking insufficient levels to other serious diseases has many now referring to it as the "good-health vitamin."
The suggested minimum serum level of 25-hydroxyvitamin D is considered to be between 20 and 30 ng/mL. Research shows levels lower than this compromise bone-mineral density and have also been implicated in cardiovascular disease, immune dysfunction, hypertension, diabetes, and cancer, among others.
According to the authors, vitamin D "exerts antithrombotic and neuroprotective effects."
"We are of the opinion that it is a promising and safe preventive/therapeutic approach to supplement vitamin D in patients after stroke and at high risk for stroke to maintain 25-hydroxyvitamin D concentrations of at least 75 nmol/L (30 ng/mL), which have been shown to be most effective in producing favorable health outcomes," they conclude.
The authors have no relevant disclosures.
Stroke. Published online July 17, 2008. Abstract
Medscape Medical News © 2008 Medscape
Cite this: Caroline Cassels. Low Vitamin D Levels Independent Predictor of Fatal Stroke - Medscape - Jul 24, 2008.