Temporal and geographic variation in hip fracture rates for people aged 65 or older, New York State, 1985-1996

Abstract

We describe temporal and regional variation in hip fracture rates for people aged 65 or older in New York state (NYS) from 1985 to 1996. Our descriptive study was of all hip fracture cases admitted to NYS hospitals during that period. Case data were obtained from the Statewide Planning and Research Cooperative System (SPARCS) of the NYS Department of Health. US Census Bureau population estimates were obtained for each year from 1985 to 1996 to compute the annual hip fracture rate for each NYS county. These rates were adjusted for differences in age, gender, and race and were compared using logistic regression. Approximately 14,000 hip fractures occurred annually from 1985 to 1996. The annual rate (number of hip fractures per 1000 population) decreased from 6.4 in 1985 to 5.3 in 1996. White women aged 85 or older had the highest rate (26/1000); nonwhite men aged 65 to 69 had the lowest rate (<1/1000). Statewide annual rates decreased slightly over time, but this change was not reflected in all age, gender, and race subgroups. There was important, consistent variation in county rates after adjustment for age, gender, and race. Other researchers have identified geographic variation in national rates, but the postulated environmental and weather-related factors (eg, water fluoridation use; rainfall and sunshine amounts) have explained only a small proportion of this variation. Identification of risk factors that can better explain regional rate variation may lead to development of intervention strategies that could significantly reduce the risk for hip fracture among people 65 or older.