FRAX-based intervention and assessment thresholds for osteoporosis in Iran

Area of Science:

• Osteoporosis management and fracture risk assessment.
• Clinical guideline evaluation in women's health.

Background:

• The Fracture Risk Assessment Tool (FRAX®) has been calibrated for Iran.
• Clinical practice guidance is needed for applying FRAX fracture probabilities.

Purpose of the Study:

• To compare the effectiveness of current Iranian osteoporosis guidelines (BMD T-score ≤ -2.5 SD) with FRAX-based intervention thresholds.
• To evaluate if FRAX-based thresholds can better identify women at high risk of osteoporotic fractures.

Main Methods:

• Calculated age-specific 10-year probabilities for major osteoporotic fractures using FRAX in women with average BMI.
• Determined intervention thresholds based on T-score ≤ -2.5 SD and fracture probabilities equivalent to a prior fragility fracture.
• Explored parsimonious use of Bone Mineral Density (BMD) testing with assessment thresholds.

Main Results:

• A T-score threshold of ≤ -2.5 SD identified significantly higher FRAX probabilities in younger women compared to average BMI women.
• The effectiveness of the T-score threshold decreased with age, becoming protective in women aged 80+.
• FRAX-based thresholds equivalent to a prior fracture identified women at increased risk across all ages, with probabilities rising from 4.9% at age 50 to 17% at age 80.

Conclusions:

• Bone Mineral Density (BMD) thresholds alone are insufficient for effectively targeting women at high fracture risk, particularly the elderly.
• FRAX-based intervention thresholds, equivalent to a "fracture threshold," are more effective in identifying women at high risk of osteoporotic fractures.