Study Finds FRAX Score Could Be Missing the Mark for Women in the US

Carolyn Crandall, MD, MS, MACP
Credit: UCLA Health

New research is underlining the need for more accurate risk prediction models for postmenopausal fractures.

Results of the study, which examined use of the Fracture Risk Assessment Tool (FRAX) and the Osteoporosis Self-assessment Tool (OST), prompted investigators to purport the US version of FRAX should not be used in making screening decisions for postmenopausal women, which contradicts recommendations from the US Preventive Task Force (USPSTF) endorsing use of FRAX.¹

“Identifying women with osteoporosis by bone density is the goal of screening, because those women are potential candidates for osteoporosis drug therapy,” said lead investigator Carolyn Crandall, MD,MS, MACP, professor of medicine in the division of general internal medicine and health services research at the David Geffen School of Medicine at UCLA.² “For that purpose, OST performs better than FRAX, is simpler to use, and doesn’t require the inclusion of race or ethnicity information."

As the health care community continues to embrace the idea of precision medicine, the utility of risk scores and prediction models for real-world use has been placed in the spotlight. In the current study, Crandall and a team of colleagues sought to estimate the ability of FRAX to distinguish between women aged 50-64 years who do and do not experience fracture across 4 racial and ethnic subgroups: Asian women, Black women, Hispanic women, and White women.¹

With this in mind, investigators designed their study as an analysis of data from the Women’s Health Initiative, which collected data from more than 160,000 postmenopausal women from 40 centers across the US between 1993-1998. Limiting their study to participants aged 50-64 years at baseline, with 10 years of follow-up and without reports of previous osteoporosis medication use, investigators identified a final analytic cohort of 67,169 participants.¹

Investigators noted OST was chosen as the comparator as it does not include race and ethnicity information, but is another tool recommended by the USPTF to identify postmenopausal women younger than 65 years at risk of osteoporosis. The primary outcome of interest for the study was the area under the receiver operating characteristic curve (AUC) for FRAX without bone mineral density information and OST for incident major osteoporotic fracture and bone mineral density within each racial and ethnic category. Investigators pointed out the analysis of discrimination of bone mineral density included a subset of 4607 women.¹

When assessing discrimination of major osteoporotic fractures, AUC values for FRAX were as follows¹:


• 0.65 (95% CI, 0.58-0.71) for Asian women
• 0.55 (95% CI, 0.52-0.59) for Black women
• 0.61 (95% CI, 0.56-0.65) for Hispanic women
• 0.59 (95% CI, 0.58-0.59) for White women

When assessing discrimination of major osteoporotic fractures, AUC values for OST were as follows¹:

• 0.62 (95% CI, 0.56-0.69) for Asian women
• 0.53 (95% CI, 0.50-0.57) for Black women
• 0.58 (95% CI, 0.54-0.62) for Hispanic women
• 0.55 (95% CI, 0.54-0.56) for White women

Investigators pointed out further analysis suggested AUC values for discrimination of femoral neck osteoporosis were excellent for OST (range, 0.79 [95% CI, 0.65-0.93] to 0.85 [95% CI, 0.74-0.96]), higher for OST than FRAX (range, 0.72 [95% CI, 0.68-0.75] to 0.74 [95% CI, 0.60-0.88]), and similar in each of the 4 racial and ethnic groups.¹

“The US version of FRAX should not be routinely used to make screening decisions in younger postmenopausal women. Future investigations should improve existing tools or create new approaches to osteoporosis risk assessment for this age group,” wrote investigators.¹

References:

Crandall CJ, Larson JC, Schousboe JT, et al. Race and Ethnicity and Fracture Prediction Among Younger Postmenopausal Women in the Women’s Health Initiative Study. JAMA Intern Med. Published online May 22, 2023. doi:10.1001/jamainternmed.2023.1253

UCLA Health. A commonly used tool is suboptimal in predicting osteoporosis fracture risk in younger post-menopausal women. EurekAlert! May 22, 2023. Accessed May 22, 2023. https://www.eurekalert.org/news-releases/989815.