BMI May Predict Osteoporosis in Younger Postmenopausal Women

BMI demonstrated higher sensitivity than other screening methods in predicting osteoporosis in younger postmenopausal women, according to data presented at the North American Menopause Society (NAMS) 2014 Annual Meeting.

Previous studies suggest that low BMI may be a risk factor for osteoporosis. In this study, researchers compared the use of BMI as a predictor for osteoporosis development with current screening strategies, including 10-year osteoporotic fracture risk according to the FRAX tool (the United States Preventive Services Task Force [USPSTF] strategy) without bone mineral density (BMD), a risk factor-based approach and the Osteoporosis Self-Assessment Tool (OST).

After study recruitment, the researchers surveyed women about their age, weight, height, race, history of fragility fracture after age 50 years, parental hip fracture, ever or current long-term steroid use, current smoking status and medical history of rheumatoid arthritis.

Dual-energy x-ray absorptiometry (DXA) results were used as the gold standard for screening.

A total of 445 postmenopausal women aged 50 to 64 years were included in the study. Thirty-eight had osteoporosis and three had a history of fragility fracture, according to the study results.

The researchers reported that sensitivity and specificity were 24% and 83% for the USPSTF strategy; 66% and 62% for the risk factor-based method; and 79% and 56% for OST, respectively.

Using the receiver operating characteristic (ROC) curve, the researcher identified a BMI of 28 as the best cut point for identifying osteoporosis. Sensitivity and specificity were 95% and 38%, respectively.

The researchers also noted that BMI alone, the USPSTF screening strategy, OST and the risk factor-based method required nine, nine, seven and seven women, respectively, to undergo DXA to identify one woman with osteoporosis.

“BMI is a very important predictor of osteoporosis in the younger postmenopausal population. Using BMI ≤28 as a cut point corresponds to a much higher sensitivity compared to other screening modalities without significantly increasing the cost,” the researchers concluded.

They noted, however, that larger multicenter prospective studies are needed to confirm their findings.

Reference

1. Jiang X et al. Abstract S-4. Presented at: North American Menopause Society (NAMS) 2014 Annual Meeting; Oct. 15-18, 2014; Washington, D.C.