Increased Vitamin D Might Make Bisphosphonates More EffectiveJun 9, 2011 | Parker Waichman LLP
Vitamin D supplementation might help bisphosphonates like Fosamax do a better job of protecting bones, a new study says. The study, conducted by researchers at the Hospital for Special Surgery in New York, found that maintaining a circulating vitamin D level above 33 ng/m increases the success of bone drug density drug therapy seven-fold.
The study is the first to formally examin vitamin D levels and outcomes for improving bone mineral density and loss with the use of the FDA approved drugs Fosamax, Actonel, Boniva and Zometa.
"There has been a lot of controversy over the correct vitamin D levels for people to have," said the lead author of the study, Dr. Richard Bockman, chief of the endocrine service at Hospital for Special Surgery in New York, in a news release. "Vitamin D status should be optimized to improve outcomes in patients taking bisphosphonates."
To reach their conclusions, the researchers conducted a chart review of patients evaluated in an osteoporosis practice of Hospital for Special Surgery. Women included had been taking one of the four bisphosphonates daily for at least 18 months, were postmenopausal and had at least two bone mineral density scans 18 to 60 months away from the first scan. The researchers looked at bone density T scores, history of fractures, calcium supplementation, body mass index and length of time of any of osteoporosis drugs were used.
The researchers evaluated vitamin D levels at the time of bone scan and levels in between. Women responding to bone density drugs were considered those who had not sustained a fracture, less than 3 percent decrease in bone mineral density between the initial bone scan and follow up testing.
The study included 160 patients, of which 42 had decreased bone mass density. Twelve had a low T score that persisted and 17 sustained a fracture, making 71 of the participants unresponsive to the therapy. Of the unresponsive group, 54.9 percent had circulating vitamin D levels below 33 ng/ml.
Those with higher levels had a seven fold increased likelihood of successful treatment bisphosphonates.
The study adds to the evidence that the current recommendations for vitamin D may be too low. According to a report from the Los Angeles Times, the Institute of Medicine last year issued a report that declined to make changes to the current vitamin D recommendation, despite many new studies supporting the need for more vitamin D than is typically consumed. That report maintained that vitamin D levels of 20 ng/ml to 30 ng/ml are adequate for most normal, healthy adults.