Our Target is NO NEW FRACTURES. The original goal by DXA was a T-score of -2.4 or better. But age is a huge factor in actual fracture risk. The fracture risk of a T-score of -2.5 at age 60 is the same as a T-score of -3.1 at age 50, is the same as a T-score of -1.3 at age 80.
FRAX was developed by WHO and the International Osteoporosis Foundation to take age and other factors into account. The big 5 risk factors are age, previous fracture, parental hip fracture, smoking, and oral or inhaled corticosteroids. Rheumatoid arthritis (or diabetes), over 3 doses of alcohol daily, and BMI < 19 or > 35 also count. Male and Female are different. Femoral Neck of the hip BMD by DXA is only 30% of the calculation when available.
Treat to Target by FRAX is a “Major Osteoporotic” (wrist, shoulder, hip or clinically noticed spine) Fracture Risk of < 20%. Alternately a Hip Fracture Risk of < 3.0 is the target. FRAX identifies a more individualized fracture risk than DXA with or without fragility fracture.
Look up the FRAX tool at http://www.sheffield.ac.uk/FRAX/
FRAX gives different targets than DXA because it takes additional risk factors into account. And there have been some refinements added.
Jay Ginther, MD