The impact of decreasing U.S. hip fracture rates on future hip fracture estimates

Abstract

Summary: We examined age- and sex-specific hip fracture hospitalization rates among people aged 65 and older using 1990-2010 National Hospital Discharge Survey data. Trends calculated using Joinpoint regression analysis suggest that future increases in hip fractures due to the aging population will be largely offset by decreasing hip fracture rates among women. However, this trend will be counterbalanced by rising numbers of hip fractures among men.

Introduction: From 1990 to 2006, age-adjusted U.S. hip fracture rates among people aged 65 years and older declined significantly. We wanted to determine whether decreasing age group-specific hip fracture rates might offset increases in hip fractures among the aging population over the next two decades.

Methods: This study used data from the National Hospital Discharge Survey, a national probability survey of inpatient discharges from nonfederal U.S. hospitals, to analyze hip fracture hospitalizations, defined as cases with first diagnosis coded ICD-9 CM 820. We analyzed trends in rates by sex and 10-year age groups using Joinpoint analysis software and used the results and projected population estimates to obtain the expected number of hip fractures in 2020 and 2050.

Results: Based on current age- and sex-specific trends in hip fracture hospitalization rates, the number of hip fractures is projected to rise 11.9 %-from 258,000 in 2010 to 289,000 (Projection Interval [PI] = 193,000-419,000) in 2030. The number of hip fractures among men is expected to increase 51.8 % (PI = 15.9-119.4 %) while the number among women is expected to decrease 3.5 % (PI = -44.3-37.3 %). These trends will affect the future distribution of hip fractures among the older population.

Conclusions: Although the number of older people in the U.S.A. will increase appreciably over the next 20 years, the expected increase in the total number of hip fractures will be largely offset by decreasing hip fracture rates among women. However, this trend will be counterbalanced by rising numbers of hip fractures among men.