Hip fracture is associated with an increase in short-term mortality—defined as death within one year—for women ages 65 to 79 years and healthy women ages 80 years and older, although the risk returns to previous levels after one year for women ages 70 years and older, a newly released report says.

The report was published online by the journal Archives of Internal Medicine.

Nearly 300,000 hip fractures occur each year in the U.S., causing substantial short- and long-term disability and increased mortality. Previous research to determine the mortality risk associated with hip fracture hasn't always accounted for differences in health status, say the authors of this latest study.

"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," the authors say in their report.

Additionally, studies that explored the influence of age on mortality after hip fracture have reported conflicting findings. The researchers in the new study sought to determine the short-term, intermediate-term (between one and five years) and long-term (between five and 10 years) mortality associated with hip fracture. They also looked at whether healthy women ages 80 years and older would have increased mortality associated with hip fracture when compared with other healthy women of the same age.

Dr. Erin S. LeBlanc, of the Center for Health Research, Kaiser Permanente Northwest, in Portland, Ore., and colleagues evaluated participants in the Study of Osteoporotic Fractures, a large community-based, multicenter study.

Participants were recruited between 1986 and 1988 and followed until December 2005; the mean (average) follow-up was 14.4 years. The researchers selected 1,116 women with hip fracture and matched each with four control participants of the same age who didn't have hip fracture for a total of 5,580 participants.

Through a healthy older subset of 960 participants ages 80 years or older who attended a 10-year follow-up examination and reported good or excellent health, the researchers were able to examine the association with health status. The authors determined where they termed "incident," or new-onset, hip fractures by examining radiology reports, and used death certificates to confirm participants' deaths.

For participants with hip fracture, the odds of death were twice as high in the year after the fracture as were controls, at 16.9 percent versus 8.4 percent. The odds of short-term mortality increased in participants ages 65 to 70 (16.3 percent vs. 3.7 percent) and 70 to 79 (16.5 percent vs. 8.9 percent).

An increase also was observed in women ages 80 and older with good or excellent health (15.1 percent vs. 7.2 percent). After one year following fracture, participants with fracture and controls had similar mortality, except those ages 65 to 70 years with fractures, who continued to have an increase in mortality.

The authors note that, because the risk of hip fracture increases with age, hip fractures may become an even larger public health issue as the population ages.

"If our findings are replicated, they would suggest that research should focus on hip fracture prevention and interventions in these groups that could decrease mortality during that high-risk period," they write.