Cleveland – If you’re serious about practicing evidence-based medicine, you’ll back off on the bisphosphonates and focus on increasing vitamin D when working with patients at risk for osteoporosis.
“Look closely at the data for bisphosphonates. It just doesn’t hold up,” said Tieraona Low Dog, MD, at the annual meeting of the American Holistic Medical Association (AHMA).
A number of guidelines recommend that most if not all post-menopausal women should be on bisphosphonate drugs to prevent osteoporosis. This is based on the oft –repeated figures that over 50% of all women and 13% of all men above 50 years of age will have an osteoporosis-associated fracture at some point.
What those scary numbers don’t tell you is that the average age for hip fractures, the most worrisome of the osteoporosis-related outcomes, is 79 years. Do people really need to be on expensive prescription medications with considerable side effects for nearly 30 years to prevent fractures? It’s a very important question, said Dr. Low Dog, who is Director of the Fellowship in Integrative Medicine at the University of Arizona, Tucson.
Further, do bisphosphonates really prevent osteoporosis-related fractures? It might be logical to think they would, but the data say they do not. A Cochrane Collaboration systematic review of 11 clinical trials of alendronate (Fosamax), representing over 12,000 post-menopausal women, showed that at 10 mg per day, the most commonly used dose, there was no primary prevention of osteoporosis-associated hip fractures. The women receiving alendronate in these 11 studies were compared against women of similar age and health status who took placebo or calcium and vitamin D supplements.
The drug did give a 2% net absolute risk reduction for first vertebral fractures, and a 6% absolute risk reduction for secondary vertebral fractures, as well as a 2% absolute risk reduction in secondary non-vertebral fractures (Wells GA, et al. Cochrane Database Syst Rev. 2008; 23(1): CD001155).
Overall, the science supporting widespread use of alendronate for fracture prevention is pretty weak, especially given the numbers of patients treated and the life-long duration of treatment. The data on risedronate (Actonel) is equally flimsy, said Dr. Low Dog, who practices in Albuquerque, NM.
Researchers at the Bone & Mineral Research Laboratory, Henry Ford Hospital, Detroit published a study showing considerable prevalence of vitamin D deficiency among elderly women and men seeking medical advice for osteoporosis.
They looked at 2,924 consecutive patients, who had a mean age of 68 years. Using a very extreme criterion of <15 ng/ml for 25 (OH) vitamin D in serum as the cut-off, they found that 15% of these people were deficient. With a more relaxed criterion of <20 ng/ml, the prevalence of deficiency was 32%. More than 70% of the patients would be considered deficient with a <30 ng/ml cut-off (Guardia G, et al. Osteoporosis Int. 2008; 19(1): 9-13). The authors noted that these prevalence figures remained more or less constant over a 5-year period.
Dr. Low Dog noted that by using vitamin D supplementation, at a moderate daily dose of 700-800 IU/D, you’d have to treat 45 women for 2 years in order to prevent one fracture. This compares very favorably with the 91 patients one would need to treat with alendronate for 3 years, to prevent one fracture. The number needed to treat with risedronate is 77, for 3 years.
She added that vitamin D not only protects and improves bone mineral density, it also improves muscle function, reducing the risk of falling, which is a primary direct cause of fractures in the elderly.
“When vitamin D is deficient, parathyroid hormone goes way, way up, and this leads to a decrease in proximal muscle strength, increasing your susceptibility to falls. When you replenish vitamin D, the muscle tone improves, and patients have better balance, better gait.”
Though there is still a lot of controversy over the precise definition of vitamin D deficiency and the optimal form of the vitamin to use for supplementation, and the ideal serum level, it seems vitamin D is a better and cheaper long term bet than bisphosphonate drugs for primary fracture prevention in the elderly.
To read more on this topic, subscribe to our Premium Web Access and search, “Vitamin D” and “Osteoporosis.”
