Impact of Traumatic Brain Injury on Recovery over the Year Following Hip Fracture among Older Medicare Beneficiaries

Background Traumatic brain injury (TBI) is a serious full-related injury that could occur simultaneously during the fall that resulted in hip fracture. The objective of the current study was to estimate the impact of TBI on days at home (DAH) among older adults hospitalized with hip fracture. Methods We identified community-dwelling Medicare beneficiaries aged 65 and older and hospitalized with hip fracture hospitalized with hip fracture 2010-2017 from Medicare administrative claims data. TBI was identified during the hospitalization episode. DAH was calculated by subtracting the number of days spent in an inpatient, skilled nursing facility, nursing home, emergency department observation, or outpatient observation setting, and the number of days spent deceased, from the total follow-up available for each of the twelve follow-up months (ie 365 days). We modelled the sum of DAH as a function of TBI using overlap weighting in a Poisson regression model. Results Among 101,196 Medicare beneficiaries hospitalized with hip fracture between 2010-2017, average age was 83.5 (SD 8.1), 72.7% were female, and and 3,121 (3.1%) met our criteria for concurrent TBI. Beneficiaries with TBI were older with a higher burden of comorbidities and more likely to die during the 12-month follow-up. Beneficiaries with TBI had fewer DAH after hip fracture (199.7 (SD 140.9) vs. 229.7 (SD 133.9), p<.001). Following overlap weighting, TBI was associated with significantly reduced DAH (rate ratio 0.90; 95% confidence interval 0.90, 0.91). Conclusions Results suggest that any head injury in the setting of hip fracture may confer meaningful morbidity beyond the already well-documented increases in mortality. Future studies should examine whether improved management of TBI would optimize recovery following hip fracture.