The Study of Osteoporotic Fractures (SOF) recruited 9704 community-dwelling women 65 years or older (>99% non-Hispanic white) in the USA. Women who were unable to walk without assistance and those with bilateral hip replacements were excluded. All women provided written consent, and the SOF was approved by each site’s institutional review board.
Background Fractures have been associated with subsequent increases in mortality, but it is unknown how long that increase persists.
Methods A total of 5580 women from a large community-based, multicenter US prospective cohort of 9704 (Study of Osteoporotic Fractures) were observed prospectively for almost 20 years. We age-matched 1116 hip fracture cases with 4 control participants. To examine the effect of health status, we examined a healthy older subset of 80 years or older who attended the 10-year follow-up examination and reported good or excellent health. Incident hip fractures were adjudicated from radiology reports by study physicians. Death was confirmed by death certificates.
Results Hip fracture cases had 2-fold increased mortality in the year after fracture compared with controls (16.9% vs 8.4%.) When examined by age and health status, short-term mortality was increased in those aged 65 to 69 years (16.3% vs 3.7%), 70 to 79 years (16.5% vs 8.9%), and only in those 80 years or older with good or excellent health (15.1% vs 7.2%). After the first year, survival of hip fracture cases and controls was similar except in those aged 65 to 69 years, who continued to have increased mortality.
Conclusions Short-term mortality is increased after hip fracture in women aged 65 to 79 years and in exceptionally healthy women 80 years or older. Women 70 years or older return to previous risk levels after a year. Interventions are needed to decrease mortality in the year after hip fracture, when mortality risk is highest.
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Hip fractures are a major public health problem, with nearly 300 000 occurring annually in the United States. Hip fractures cause substantial short- and long-term disability as well as increased mortality.
In a recent meta-analysis, women had nearly 3-fold increased mortality risk in the year after hip fracture. Long-term (10-year) mortality data are mixed. In the meta-analysis,excess mortality risk from hip fracture decreased during the first 2 years after fracture but did not return to the rate of age-matched control participants during long-term (10-year) follow-up.
Previous mortality risk estimates have some important limitations. Some studies used hospitalized patients or registries to identify samples while drawing controls from the general community. Such studies are likely biased by differences in the health status of hip fracture cases compared with nonfracture controls. The use of hospitalized patients or registries also does not allow for examination of health status or other important covariates, such as bone mineral density (BMD), before fracture occurrence. Other studies have combined nursing home residents and community-dwelling women, populations that would be expected to have very different health status.
Such methodological limitations have made it difficult to determine whether the noted increase in mortality after hip fracture is the result of underlying poor health or the hip fracture itself. Some studies have found that healthy participants without comorbidities have no increased mortality risk after hip fracture and have concluded that comorbidities explain much of the increased mortality risk after hip fracture others have noted higher mortality in individuals without comorbidities compared with those with comorbidities.
Previous studies exploring the influence of age on mortality after hip fracture have conflicting results, and limitations include insufficient information about health status and the use of registries to retrospectively identify cases.Some studies have found that mortality after hip fracture increases with age. However, in several studies from Europe,the relative risk of death after hip fracture compared with the risk of death in the general population was lower in older vs younger patients with hip fracture.
Among 5580 community-dwelling ambulatory women 65 years or older enrolled in our prospective cohort (1116 incident hip fracture cases and 4464 age-matched controls), our aim was to determine the short-term (≤1 year), intermediate-term (>1 to ≤5 years), and long-term (>5 to ≤10 years) mortality associated with hip fracture. Because expected mortality rates increase significantly with advanced age combined with poor health, a secondary aim was to determine whether healthy women 80 years or older would have increased mortality associated with hip fracture compared with healthy age-matched controls.
Erin S. LeBlanc, MD, MPH; Teresa A. Hillier, MD, MS; Kathryn L. Pedula, MS; Joanne H. Rizzo, MPA; Peggy M. Cawthon, PhD, MPH; Howard A. Fink, MD, MPH; Jane A. Cauley, DrPH; Douglas C. Bauer, MD; Dennis M. Black, PhD; Steven R. Cummings, MD; Warren S. Browner, MD
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