A second bone mineral density (BMD) scan up to eight years after an initial BMD appears to provide little additional benefit for predicting fractures among older postmenopausal women, according to a report in the January 22 issue of Archives of Internal Medicine.
Current guidelines recommend screening all women at age 65 for osteoporosis by using BMD measurements.
Teresa A. Hillier, M.D., M.S., of Kaiser Permanente Northwest/Hawaii, and colleagues measured total hip BMD in 4,124 older women (average age 72 years) and again approximately eight years later. The researchers calculated the rate of change in BMD in women for an average of five years after the repeated BMD to see which women developed fractures (which were verified through radiology reports and x-ray films).
During the follow-up period, 877 women had a non-traumatic non-spine fracture, including 275 hip fractures, and 340 women developed a spine fracture. On average, the women’s initial BMD measurements were low but not in the osteoporotic range. The group lost an average of .59 percent of their bone mass per year between examinations.
In four BMD models (initial BMD, repeat BMD, change in BMD between the two examinations, and initial BMD plus change in BMD), BMD was a significant predictor of incident non-spine and hip fracture risk as well as being associated with morphometric spine fractures.
However, the authors did not find any increase in the overall predictive value with a second BMD measurement. The researchers concluded that repeated BMD measurements have limited value in classifying risk for future fractures in average healthy older woman 65 years or older.
Despite this initial finding, the researchers indicated a repeated BMD measurement might be useful in some women, including those with factors that contribute to rapid bone loss and in younger women in early menopause.
About the Author
Jeanne Bohm, Ph.D. is a cancer biologist by training, a medical writer and an experienced science educator.
The author has no financial relationship to any of the companies listed in the article.