Press Release

Embargoed for Release at 5:30 PM ET, Friday Oct. 24, 2003

Arthritis News

BENEFITS OF OSTEOPOROSIS TREATMENT ON FRACTURE RISK MAY BE GREAT, EVEN WHEN IMPROVEMENT IN BONE DENSITY IS SMALL

ORLANDO, FLORIDA—A recent study revealed that reduction in fracture risk from risedronate, a bisphosphonate medication commonly used to treat patients who have osteoporosis, is seen even in patients who have only small improvements in bone mass as measured by bone density, according to research presented this week at the American College of Rheumatology Annual Scientific Meeting in Orlando, Florida.

Researchers reanalyzed data from the HIP and VERT studies of risedronate, which included nearly 9,000 patients from two randomized, double-blind clinical trials. Patients were selected to receive risedronate or placebo based on low bone mineral density (an indicator of bone strength) and/or pre-existing vertebral fracture. All patients also received daily supplements of calcium and vitamin D if baseline levels were low. Researchers examined the relationship between new vertebral fractures and changes in lumbar spine bone mineral density in both the placebo and risedronate groups. The results confirm that increases in bone mineral density results in a reduction in patients’ risk for fracture as compared to those whose bone mineral density decreases. Patients taking risedronate had a decreased risk of fracture compared to those taking placebo. Further, the results show that there was a significant reduction in fracture risk in all patients who had improvements in bone density, and that the reduction in fracture risk was independent of the magnitude of the improvement. Comparisons of bone mineral density increases among different therapies may not translate into meaningful differences in reducing fracture risk.

Fracture is a leading cause of disability in patients with osteoporosis, which affects 10 million people in the U.S., the majority of whom are women.

“Bone density measurements have helped us identify those who are at high risk for fractures,” said Jonathan Adachi, MD, Professor and Director of the Arthritis Centre at St. Joseph’s Hospital-McMaster University in Hamilton, Ontario, Canada, an investigator on the study. “In following patients on therapy, our study suggests that even moderate increases in bone density offer treatment benefit that is not significantly different from larger increases. This suggests that there may be a threshold above which further increases in bone density have little effect on fracture benefit. This also reinforces the need for further research to determine how osteoporosis therapies influence other elements of bone quality that affect the risk of fracture, such as bone turnover and bone micro-architecture.”

The American College of Rheumatology is the professional organization for rheumatologists and health professionals who share a dedication to healing, preventing disability and curing arthritis and related rheumatic and musculoskeletal diseases. For more information on the ACR’s annual meeting, see www.rheumatology.org/annual.

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