SAN DIEGO – Combined daily supplementation with folic acid and vitamins B6 and B12 proved to be a bust for reduction of nonvertebral fracture risk in a large, randomized, double-blind clinical trial conducted in women with known cardiovascular disease or multiple risk factors.
A secondary analysis of fracture outcomes in 5,442 female health professionals over age 42 years who participated in the Women’s Antioxidant and Folic Acid Cardiovascular Study (WAFACS) showed an overall nonvertebral fracture incidence of 7.6% during an average 7.3 years of treatment and follow-up in the supplementation group and a similar 6.9% rate in placebo-treated controls, Dr. Douglas C. Bauer reported at the annual meeting of the American Society for Bone and Mineral Research.
Participants in WAFACS had known cardiovascular disease or three or more cardiovascular risk factors. The previously reported primary study end points were cardiovascular event rates and all-cause mortality, where supplements had no effect (JAMA 2008;299:2027-36).
The new retrospective secondary analysis of WAFACS was undertaken because some prior observational studies had concluded that elevated homocysteine and low vitamin B12 levels are associated with increased fracture risk. The supplement regimen utilized in the trial was designed to lower homocysteine and boost vitamin B12 levels. It consisted of daily folic acid at 2.5 mg, vitamin B6 at 50 mg, and vitamin B12 at 1 mg.
In all, 80% of participants reported greater than 66% compliance with therapy. Rates of hip, wrist, and total nonspine fractures were similar in both high-compliance subgroups, noted Dr. Bauer of the University of California, San Francisco.
WAFACS was funded by the National Heart, Lung, and Blood Institute. Dr. Bauer reported having no financial conflicts.