We read with interest the letter by Icks et al. concerning the declining trend in hip fracture incidence among young adults in Germany.1 The authors used the German National Register of Hospital Discharges to identify hip fractures occurring between 1995 and 2004, and reported a decrease in hip fracture incidence among both men and women younger than 40 years old during this time period.
There are important methodological details left out of this letter, including the disease or surgical codes included for case identification, whether the National Register includes all hospitals in Germany or a sampling of discharges, how changes in the codification system over the 10-year period2,3 may have affected the results, and the method for excluding individuals with a prior hip fracture. Mistakes in the codification of hip fracture have been previously noted.4 In order to assess whether this trend is real, additional information is needed.
More importantly, Icks et al. report an overall 5% increase in the age-adjusted incidence of hip fracture in Germany. Assuming that this increase is real, this suggests that the increase among older adults (aged 50 years and older) is 5% or greater. Studies from other countries report increased, constant, or decreased incidence of hip fracture among adults aged 50 years and older during a similar time period.5,6
Regardless of the temporal trend, the vast majority (approximately 90%) of hip fracture cases worldwide occur among individuals aged 50 years or older. More individuals are living longer now than ever before. Thus, even while the overall incidence of hip fracture may decrease or remain constant, the total number of cases and health care expenditures related to hip fracture later in life are significant and are projected to rise.7,8 Health disparities among older adults may contribute to an increased hip fracture burden in certain population groups. In a nationally representative sample of older US adults, we found significant risks related to health insurance, educational status, and housing type that were attributed to over one third of new hip fracture cases.9 This represents a significant public health concern.
Hip fracture is one of the most seriously debilitating but preventable injuries among individuals aged 65 years and older. Among this group, approximately one half of White women and one quarter of White men will sustain at least 1 osteoporotic fracture in their remaining lifetime.10 Although reporting successes in injury prevention among younger adults is of importance, the burden of hip fracture among older adults requires continued vigilance in primary and secondary prevention.
References
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