FRAX-based Estimates of 10-year Probability of Hip and Major Osteoporotic Fracture Among Adults Aged 40 and Over: United States, 2013 and 2014

Abstract

Background: The FRAX algorithm estimates the 10-year probability of hip and major osteoporotic (clinical spine, forearm, hip, or humerus) fracture for adults aged 40 and over. An expert panel developed criteria to define elevated FRAX probabilities for U.S. adults aged 50 and over. This report uses FRAX estimates from the National Health and Nutrition Examination Survey 2013-2014 to describe the hip and major osteoporotic fracture probability distribution (for adults aged 40 and over) and prevalence of elevated probabilities (for adults aged 50 and over) in the United States.

Methods: FRAX U.S. version 3.05 was used to calculate fracture probability from risk factors that were measured (i.e., femur neck bone mineral density, height, and weight) or self-reported (i.e., fracture history, glucocorticoid use, rheumatoid arthritis, smoking, and alcohol intake). Among adults aged 50 and over, elevated probabilities were defined as 3% or greater for hip fracture and 20% or greater for major osteoporotic fracture.

Results: Mean skew-adjusted fracture probabilities were 0.5% for hip fracture and 5.3% for major osteoporotic fracture among adults aged 40 and over, and 0.9% and 7.4%, respectively, among adults aged 50 and over. The percentages of adults aged 50 and over with an elevated hip or major osteoporotic fracture probability were 19% and 8%, respectively. Fracture probabilities varied significantly by age (older groups had higher probabilities than younger groups), sex (women had higher probabilities than men), and race and Hispanic origin (non-Hispanic white persons had higher probabilities than all other race and Hispanic groups) (p < 0.001). An estimated 95%-97% of adults aged 50 and over with an elevated probability of either fracture type had femoral neck osteoporosis or low bone mass.

Conclusions: Mean hip and major osteoporotic fracture probabilities were 0.5% and 5.3%, respectively, for adults aged 40 and over. Among adults aged 50 and over, mean hip and major osteoporotic fracture probabilities were 0.9% (19% with elevated values) and 7.4% (8% with elevated values), respectively.

Keywords: National Health and Nutrition Examination Survey; fracture risk prediction; osteoporosis.