FRAX calculations overlook many women at risk for osteoporotic fracture
Fracture Risk Assessment Tool calculations fail to identify many women who are likely to experience a major osteoporotic fracture or hip fracture during the next 10 years, according to recent study findings presented at The North American Menopause Society Annual Meeting.
In a systematic review and meta-analysis, researchers found that the Fracture Risk Assessment Tool (FRAX) — created to predict the likelihood that adults aged 40 to 90 years will break a bone in a fragility fracture and designed to help physicians identify osteoporosis cases not diagnosed through bone mineral density tests —has a low sensitivity for predicting future risk.
“When clinicians tell patients they are not at high risk of having fractures in 10 years based on the FRAX algorithm, they may be wrong,” Xuezhi (Daniel) Jiang, MD, assistant professor of obstetrics and gynecology at Thomas Jefferson University and obstetrics and gynecology clerkship director at Reading Hospital and Medical Center in Reading, Pennsylvania, told Endocrine Today.
“About 90% of patients who are going to have a [major osteoporotic fracture] in 10 years were not picked up by FRAX. A more sensitive [FRAX] is needed to guide clinicians and patients throughout the treatment decision-making process.”
Jiang and colleagues analyzed seven longitudinal studies (n = 57,027) from five countries (United States, Poland, France, Canada and New Zealand) to assess FRAX accuracy in predicting major osteoporotic fracture or hip fracture.
Using 20% as the 10-year fracture risk threshold for major osteoporotic fracture, mean sensitivity was 10.25% (95% CI, 3.76-25.06), mean specificity was 97.02% (95% CI, 91.17-99.03) and mean diagnostic OR was 3.71 (95% CI, 2.73-5.05). Analyzing six studies (n = 50,944) and using 3% as the 10-year fracture risk threshold for hip fracture, mean sensitivity was 45.7% (95% CI, 24.88-68.13), mean specificity was 84.7% (95% CI, 76.41-90.44) and mean diagnostic OR was 4.66 (95% CI, 2.39-9.08).
“Using the current intervention threshold (20% for major osteoporotic fracture and 3% for hip), FRAX has low sensitivity (major osteoporotic fracture, 10%; hip, 45%) in predicting fractures within next 10 years,” Jiang said. “In other words, a substantial number of women who are going to have fractures in next 10 years were missed by current FRAX calculator.
“FRAX recently just incorporated [trabecular bone score] into their algorithm; however, large, population-based, longitudinal prospective cohort studies still are needed to validate the accuracy of risk assessment in populations other than their derivation cohorts when combining FRAX and TBS,” Jiang said. “Also [trabecular bone score] is not readily available to most clinicians, and insurance coverage issues could deter clinicians from adopting it.” – by Regina Schaffer
Jiang X, et al. P-61. Presented at: The North American Menopause Society Annual Meeting; Sept. 30-Oct. 3, 2015; Las Vegas.
Disclosure: Jiang reports no relevant financial disclosures.