FRAX Score: Clinical Significance and Management

Introduction to FRAX

• The American College of Radiology recommends using FRAX, a validated fracture risk assessment tool, to calculate 10-year probability of hip fracture and major osteoporotic fracture (MOF) in postmenopausal women and men aged 50 years and older, using clinical risk factors with or without bone mineral density (BMD) 1, 2.

Treatment Thresholds

• The Journal of the American College of Radiology suggests that pharmacologic treatment is recommended when FRAX scores indicate ≥3% 10-year hip fracture risk OR ≥20% 10-year major osteoporotic fracture risk 1, 3.

Risk Stratification

• The American College of Radiology recommends considering anabolic therapy first for very high-risk patients (MOF >30% or hip fracture >4.5%) 2.
• For high-risk patients (MOF ≥20% or hip fracture ≥3%), antiresorptive therapy (bisphosphonates, denosumab) should be considered 2, 3.

Critical Adjustments

• The Arthritis and Rheumatology society recommends manually adjusting FRAX scores by multiplying MOF risk by 1.15 and hip fracture risk by 1.2 for patients taking prednisone >7.5 mg/day 2.

Predictive Accuracy

• The Journal of the American Medical Association (JAMA) states that FRAX demonstrates moderate-to-good predictive accuracy with area under the curve (AUC) values of 0.74-0.79 for hip fracture prediction and 0.67-0.71 for MOF prediction when BMD is included 1, 4.

Evidence for Screening and Treatment Benefits

• The JAMA recommends screening with FRAX followed by DXA for high-risk individuals, which reduces hip fractures by 17% (RR 0.83, 95% CI 0.73-0.93) and major osteoporotic fractures by 6% (RR 0.94, 95% CI 0.88-0.99) over 3.7-5 years 1, 4.
• Treatment with bisphosphonates in high-risk patients reduces vertebral fractures by 49% (RR 0.51, 95% CI 0.39-0.66) and hip fractures by 33% (RR 0.67, 95% CI 0.45-1.00) 4.

Screening Recommendations

• The JAMA recommends screening all postmenopausal women ≥65 years regardless of risk factors using DXA with or without FRAX 1.
• For postmenopausal women 50-64 years, screen if FRAX score (without BMD) approaches or exceeds the baseline risk of a 65-year-old white woman (approximately 9.3% 10-year MOF risk, 1.3% hip fracture risk) 1, 5.

Reassessment Intervals

• The JAMA suggests repeating FRAX assessment every 1-3 years for patients on glucocorticoids not receiving osteoporosis treatment, with earlier reassessment for very high-dose users 6, 5.

Important Limitations

• The JAMA states that FRAX uses race-specific calculators that systematically predict lower fracture risk for Asian, Black, and Hispanic individuals compared to White individuals with identical clinical profiles, potentially leading to treatment disparities 6, 5.
• FRAX does not account for dose-dependent effects of glucocorticoids, fall history, frailty status, lumbar spine BMD, trabecular bone score, diabetes mellitus, and number of prior fractures 6, 3, 7.

FRAX‑Based Osteoporosis Screening and Risk Assessment

Baseline Fracture Risk for Reference

• An older white female (≈65 years) without additional risk factors has an estimated 10‑year probability of any osteoporotic fracture of about 9 %, which is used as a reference benchmark for screening younger women. 8, 9, 10, 11

Screening Thresholds for Women Aged 50–64 Years

• Women in this age group are recommended for DXA screening when their FRAX‑derived 10‑year major osteoporotic fracture risk approaches or exceeds 9 % (the reference risk) or when the hip fracture risk reaches ≈1 %.
  Illustrative risk profiles that meet these thresholds include:

• Menopausal status should be incorporated into the decision‑making process for screening women aged 50–64 years. 9

Screening Considerations for Men

• Men whose estimated 10‑year fracture risk is equal to or greater than that of a 65‑year‑old white female without additional risk factors are the most likely to benefit from screening. 8, 9

• Current evidence is insufficient to define definitive screening guidelines for men; however, when screening is performed, the same FRAX thresholds (≥3 % hip fracture risk or ≥20 % major osteoporotic fracture risk) are applied. 8

Limitations of the FRAX Tool

• FRAX does not account for a prior history of falls, which can lead to underestimation of fracture risk. 8

• Additional risk factors not captured by FRAX (and therefore requiring clinical judgment) include: number of prior fractures, frailty status, diabetes mellitus, lumbar spine BMD, trabecular bone score, and dose‑dependent glucocorticoid effects. (These points are mentioned in the source but lack specific citations and are therefore omitted from the cited‑fact list.)