BMD loss may not signal treatment failure. (Early in Therapy).

NEW YORK -- A loss of bone mineral density during the first year of osteoporosis treatment with an antiresorptive agent may not indicate treatment failure and may be compensated for by bone mineral density gains in the second year of treatment, according to Dr. Maida Taylor.

"For the minority of patients who apparently lose bone mineral density (BMD) during the first year of treatment, the recommendation is to hang in there, because these patients are the most likely to gain BMD if the treatment is continued," she said at a gynecology symposium sponsored by Symposia Medicus.

In clinical studies with raloxifene, those patients who had the largest measurements of BMD loss in the first year of treatment tended to gain the most BMD in the second year of treatment. "Gains usually exceed the losses with raloxifene over 2 years. So, overall, the patient benefits," said Dr. Taylor, a senior research scientist for Eli Lilly, Indianapolis, which manufacturers raloxifene. She added that her comments about raloxifene generally apply to other antiresorptive agents as well.

BMD loss in the first year of antiresorptive therapy may be explained by statistical and patient variation, said Dr. Taylor, also of the University of California, San Francisco. Like any other medical diagnostic test, the BMD test yields variation. "Any measurement varies from time to time because of variation in the measurement or natural variation in the patient."

Furthermore, an extreme BMD measurement, whether a loss or gain, is likely to change and be closer to an average score upon a repeat test. ...