Incident Hip Fracture Cases Research Articles

Survival after hip fracture

Although it is known that overall mortality is increased after hip fracture, the influence of hip fracture risk factors on the subsequent mortality and cause of death has not been well studied. The objective of this study was to establish the survival after hip fracture in women and to assess the impact of comorbidity on mortality. We identified a complete population-based set of 2,245 incident hip fracture cases and 4,035 randomly selected population-based controls among women 50-81 years old in Sweden and followed these subjects for an average of 5 years through the Swedish National Inpatient and Cause-of-Death Registers. Information on factors related to hip fracture was obtained through linkage to hospital discharge data and through a mailed questionnaire. We studied excess mortality of hip fracture patients compared to controls using survival curves and proportional hazard regression models. During follow-up, 896 hip fracture patients (40%) and 516 (13%) controls died. The relative risk (RR) of death, adjusted for age and previous hospitalization for serious disease, was 2.3 (95% CI 2.0-2.5). Although the highest mortality risks were in the 1st 6 months post-fracture, RRs for fractures versus controls were increased for at least 6 years. Increased mortality was apparent both in those with evidence of comorbidity and those without. Hip fracture patients have a substantially increased risk of death that persists for at least 6 years post-fracture. The relative excess mortality is independent of comorbidity and known hip fracture risk factors.

Walking and leisure-time activity and risk of hip fracture in postmenopausal women.

Physical activity can reduce the risk of hip fractures in older women, although the required type and duration of activity have not been determined. Walking is the most common activity among older adults, and evidence suggests that it can increase femoral bone density and reduce fracture risk. To assess the relationship of walking, leisure-time activity, and risk of hip fracture among postmenopausal women. Prospective analysis begun in 1986 with 12 years of follow-up in the Nurses' Health Study cohort of registered nurses within 11 US states. A total of 61,200 postmenopausal women (aged 40-77 years and 98% white) without diagnosis of cancer, heart disease, stroke, or osteoporosis at baseline. Incident hip fracture resulting from low or moderate trauma, analyzed by intensity and duration of leisure-time activity and by time spent walking, sitting, and standing, measured at baseline and updated throughout follow-up. From 1986 to 1998, 415 incident hip fracture cases were identified. After controlling for age, body mass index, use of postmenopausal hormones, smoking, and dietary intakes in proportional hazards models, risk of hip fracture was lowered by 6% (95% confidence interval [CI], 4%-9%; P<.001) for each increase of 3 metabolic equivalent (MET)-hours per week of activity (equivalent to 1 h/wk of walking at an average pace). Active women with at least 24 MET-h/wk had a 55% lower risk of hip fracture (relative risk [RR], 0.45; 95% CI, 0.32-0.63) compared with sedentary women with less than 3 MET-h/wk. Even women with a lower risk of hip fracture due to higher body weight experienced a further reduction in risk with higher levels of activity. Risk of hip fracture decreased linearly with increasing level of activity among women not taking postmenopausal hormones (P<.001), but not among women taking hormones (P =.24). Among women who did no other exercise, walking for at least 4 h/wk was associated with a 41% lower risk of hip fracture (RR, 0.59; 95% CI, 0.37-0.94) compared with less than 1 h/wk. More time spent standing was also independently associated with lower risks. Moderate levels of activity, including walking, are associated with substantially lower risk of hip fracture in postmenopausal women.