Hip fracture rates decline in Canada

Standardized rates of hip fracture have steadily declined in Canada since 1985, with a more rapid decline between 1996 and 2005 and a more marked decrease among individuals age 55 to 64 years, according to a report in the Aug. 26 issue of the Journal of the American Medical Association.

William D. Leslie, MD, MSc, of the University of Manitoba in Winnipeg, Canada, and colleagues analyzed nationwide hospitalization data collected from the Canadian Institute for Health Information from 1985 to 2005. A total of 570,872 individuals were hospitalized for hip fracture during this time period.

Over the 21 years, age-adjusted rates of hip fracture declined 31.8% in women and 25% in men, according to a press release. The largest percentage decrease was observed among individuals aged 55 to 64 years; hip fracture rates decreased by almost one-half in women and about one-third in men in this age group.

Detailed analyses identified a more rapid decline beginning around 1996, according to the press release.

“For the overall population, the average age-adjusted annual percentage decrease in hip fracture rates was 1.2% per year from 1985 to 1996 and 2.4% per year from 1996 to 2005,” the authors wrote.

Leslie said similar trends have been reported in other countries, including the United States; however, the reasons for the decrease are not clear. The decline began before the widespread availability of bone density testing or pharmacological treatments for osteoporosis, and there is little evidence to suggest that improvements in physical activity, calcium intake, vitamin D status or prevention of falls are responsible.

“Overweight and obesity are epidemic in modern societies and may contribute to reduced fracture rates,” the authors said in the press release.

Although the percentage rates decreased, the absolute number of hip fractures increased over the study period — a phenomenon attributable to the changing age structure of the population, the authors noted.

“Hip fractures continue to exert major effects on the population — particularly the elderly — and on the health care system related to the morbidity, costs and mortality from these fractures,” they wrote. “Therefore, the decreasing incidence rates are not grounds for complacency toward osteoporosis prevention and treatment.”

Reference:
Leslie W, O’Donnell S, Jean S, et al. Trends in hip fracture rates in Canada. J Am Med Assoc. 2009;302(8):883-889.