Hip fracture - Mortality and residual lifetime risk of fractures

Abstract: Hip fracture is the most severe clinical manifestation of bone fragility. Hip fracture predominantly affects an already frail population and is associated with multi-cause morbidity and high mortality. Improved knowledge of long-term outcome is essential in order to improve future care and prevention of both fracture and its complications. In this thesis, all hip fracture patients during 1984-1985 in Malmö, Sweden (766 women, 263 men) were followed within a remaining lifetime perspective to a maximum of 26 years and compared with a background population matched for age and sex. Hip fracture patients had a higher mortality, in comparison to the control population. The size of the differences was highly dependent on age at the time of the hip fracture and whether it was a woman or a man. Excess mortality was highest during the first year following the hip fracture but remained increased for 20 years. The most common cause of death was cardiovascular disease, with a 50% relative risk increase in hip fracture patients. Despite the shorter survival and the subsequent shorter time at risk of new fractures, almost half of all female and almost one third of all male patients suffered at least one new fracture after the hip fracture. Women more often fractured on multiple occasions. The 10-year mortality-adjusted risk of new fractures was 40% for women, whereas a comparatively similar 36% risk was reached after 5 years in men. The mortality-adjusted remaining lifetime risk of new fracture was 85% for women and 62% for men. By analyzing women and men separately and by age-groups, the youngest patients, those below age 75 years, were at highest risk of new fractures, whereas patients above 85 years had a risk that was no different to that of the controls. The most common new fractures in both patients and controls were those of the hip and vertebrae, while the risk size was dependent on sex and age. These findings highlight the importance of stratifying for age and sex when analyzing outcomes both in the short and long term in hip fracture patients.