Background: Hip fractures are increasingly common and are associated with long-term sequelae, including inability to walk independently and long-term institutionalization. They are also costly from a public health or an individual perspective. The use of hip protectors might help prevent fractures by cushioning falls. Multiple factors, such as discomfort and cost, prevent patients from wearing hip protectors for sufficient periods during the day or for a sufficient number of days. Honkanen and colleagues estimated the cost-effectiveness of hip protectors in an older, community-dwelling population, using a computer simulation model.

The Study: The cost-effectiveness model had previously been applied to a nursing home population. In this study, the model was expanded to community-dwelling residents 65 years or older without prior hip fracture. The model computed probabilities for transition to a nursing home and was weighted for cohorts of different starting ages. In determining the effectiveness of hip fractures, the model also took into account efficacy (relating to the correct wearing of the hip protectors) and adherence (relating to the percentage of hours the protector is worn daily). The calculations were based on an estimated 84 percent reduction in hip fractures with hip protectors, as found in studies comparing the number of hip fractures sustained while wearing hip protectors with those occurring when hip protectors were not worn. However, because hip protectors often are not used optimally, the authors adjusted this effectiveness to a 48 percent reduction in fractures. Cost estimates were based on third-party costs to Medicare and New York State Medicaid, and hip protector costs. The analysis also included adjustments for quality-adjusted life-years (QALYs) to help predict the effect on life quality of fractures, as well as of embarrassment or discomfort associated with wearing hip protectors.

Results: Hip protector use increased life expectancy and prevented fractures in all cohorts. In the younger cohorts, hip protector use resulted in higher costs and lower QALYs. With an estimated hip fracture rate of 46 percent or higher, hip protectors were cost saving and QALY saving in women when usage began at age 80 and in men when usage began at age 85. After modifications in fracture rate estimates and QALY reductions, hip protector use remained cost-effective in women beginning at age 75 but not in men when initiated at ages younger than 85.

Conclusion: Unlike previous studies, this computer model takes into account multiple factors likely to occur over a long period to predict the cost-effectiveness of hip protector use. The authors found that the benefits of using hip protectors increased with age because of a corresponding increase in fracture risk and poorer outcomes after hip fracture. The greatest cost and QALY savings would occur if hip protector use was initiated in women 75 years or older and in men 85 years or older.