Epidemiology of hip fractures in Austria: evidence for a change in the secular trend

Abstract

Hip fracture incidence rates in Austria over a period of 20 years (1989-2008) were assessed. Age-standardized incidence rates increased until 2005 but decreased thereafter. This change in the secular trend was primarily driven by a decrease in hip fracture incidence in women. The aim of the prevailing study was to assess the incidence rates of hip fractures including changes in trend in the Austrian population over a period of 20 years (1989-2008). The number of hip fractures was obtained from the Austrian Hospital Discharge Register for the entire population ≥ 50 years of age. A correction factor for multiple registrations of the same diagnosis was determined. Incidence rates (cases per 100,000) of hip fracture were calculated in 5-year age intervals. To analyze the overall change in hip fracture for the period, average annual change expressed as incidence rate ratios (IRRs) was calculated. The age-standardized incidence in women increased until 2005, from 493 to 642, and decreased thereafter. In men, it increased at a measured pace until 2006, from 192 to 280, and decreased thereafter with a slight rebound in 2008. The age-standardized incidence in the entire population increased until 2005, from 376 to 496, and decreased thereafter. The IRR for the last 3 years (2006-2008) was significantly below the IRR for the first 17 years (0.94, ρ < 0.01), driven by a lower IRR in women (0.91, ρ < 0.01) and to a lesser extent by a lower IRR (not statistically significant) in men (0.96, ρ < 0.15). The present study indicates that since 2006, age-standardized incidence of hip fractures has been declining in the Austrian population aged 50 years and above. This reversal in the secular trend has primarily been driven by a decrease in hip fracture incidence in women.