Percentage of women whose fractures were predicted using each risk-assessment tool for three age groups.
To reduce the risk of bone fractures and their associated complications, the United States Preventive Services Task force (USPSTF) recommends that all women age 65 and older be tested and treated for low bone-mineral density. The task force also recommends that post-menopausal women ages 50 to 64 get bone-mineral-density screenings if their 10-year probability of suffering a hip, vertebral, humerus or wrist fracture is 9.3 percent or greater, based on the Fracture Risk Assessment Tool.
A new UCLA-led study, however, finds that the USPSTF strategy predicted only slightly more than one-fourth of the women who went on to experience major osteoporotic fractures within 10 years. The study also found that two older osteoporosis risk-assessment tools were not much better. The Osteoporosis Self-Assessment Tool (OST) is based on a person’s weight and age, and the Simple Calculated Osteoporosis Risk Estimation Tool (SCORE) uses race, rheumatoid arthritis, history of non-traumatic fracture, age, prior estrogen therapy and weight.
“If we want to prevent fractures, we need tools that help us accurately predict who will suffer these osteoporotic injuries, so that we can target these at-risk people for preventive measures,” says Carolyn Crandall, MD ’91 (RES ’94), professor of medicine. “Our results suggest that our current guidelines for screening in younger post-menopausal women do not accurately identify who will suffer a fracture.”
The researchers used data from the Women’s Health Initiative, which collected details about fractures during 10 years’ time and information about osteoporosis risk factors from 62,492 post-menopausal women in the United States from ages 50 to 64. Of the women studied, 85 percent were white, 9 percent were black and 4 percent were Hispanic. The average age was 57.9 years. The study found that overall, the USPSTF strategy captured only 25.8 percent of the women who suffered fractures within 10 years, SCORE captured 38.6 percent and OST caught 39.8 percent.
The authors note some weaknesses in the study. For instance, the participants of the Women’s Health Initiative may be healthier than similarly aged women whom doctors see in their clinical practices, so the findings may not generalize to others. Still, these findings suggest that the current USPSTF screening strategy does not identify the vast majority of younger post-menopausal women who experienced bone fractures, and the other strategies have significant weaknesses as well.
“Neither the USPSTF nor the other two screening strategies performed better than chance alone in discriminating among women who did and did not have subsequent fractures,” the researchers write. “These findings highlight the pressing need for the further prospective evaluation of alternative strategies, with the goal of better targeting resources to at-risk young post-menopausal women. Our findings do not support use of the USPSTF strategy or the other tools we tested to identify younger postmenopausal women who are at higher risk of fracture.”
“Comparison of Fracture Risk Prediction by the US Preventive Services Task Force Strategy and Two Alternative Strategies in Women 50-64 Years Old in the Women’s Health Initiative,” Journal of Clinical Endocrinology & Metabolism, October 16, 2014.