Increased incidence of hip fractures. A population based-study in Finland.

In Central Finland, the age-specific incidence of hip fractures did not change between the years 1982-1983 and 1992-1993 though the total number of hip fractures increased by 11% due to population aging. The objective of this study was to define the current hip fracture rates and the characteristics of patients with hip fracture. The population at risk consisted of 240,000 persons living in the Central Finland Health Care District. Hip fracture patients were identified by using the hospital discharge register, the operation lists, and the register of the Department of Anesthesiology. Patients' residential status, weight, and height, date and time of hip fracture, place of accident and mechanism and type of fracture were obtained from medical records. A total of 597 patients, 415 (69.5%) women and 182 (30.5%) men, were admitted to the hospital for treatment of an acute hip fracture in 2002-2003. The mean age of the patients was 79 (SD 13) years. Among patients aged > or =50 years (n = 577), 80.8% of the hip fractures had occurred indoors, 97.6% with a low-energetic mechanism, and 22.7% during the nighttime. The ratio of trochanteric to cervical fractures was 2:3. Between 1992-1993 and 2002-2003, the total number of hip fractures increased by 70%, from 351 to 597. The fracture rates per 1000 person-years in the age group > or =55 years were 2.0 and 3.9 in 1992-1993 and 2.8 and 5.6 in 2002-2003 for men and women, respectively. The corresponding age-adjusted incidence rate ratio (IRR) for men was 1.36 (95% CI: 1.06 to 1.76), P = 0.017, and for women 1.25 (95% CI: 1.07 to 1.47), P = 0.006. Among men, the IRR was highest in the age group 75-84 years, IRR = 1.67 (95% CI: 1.08 to 2.65), while among women, it was highest in the age group > or =85 years, IRR = 1.33 (95% CI: 1.02 to 1.75). The total number of hip fractures almost doubled within 10 years, and the age-adjusted incidence rate increased in both sexes. The accretion of the hip fracture incidence was more than could be explained merely by changes in population size and structure.