Hip fracture and depression are significant public health issues for older adults, and antidepressants are the primary treatment for depression in this population. While it is known that post-hip fracture depression impedes hip fracture recovery, and antidepressants are widely used among older adults, no studies have assessed the influence of pre-fracture depression and pre-fracture antidepressant use on hip fracture outcomes among older adults, or related sex differences. Thus, Aim 1 assessed the association between pre-fracture depression and days at home (DAH) after fracture, and related sex differences; Aim 2 examined pre-fracture antidepressant use and hospital length of stay (LOS); and Aim 3 explored the association between pre-fracture antidepressant use and mortality among hip fracture survivors with depression, and related sex differences. Medicare fee-for-service claims data was used and included community-dwelling beneficiaries with a hospitalization claim for hip fracture surgery between 2010 and 2017. Poisson regression models assessed the association between pre-fracture depression and days at home (DAH) (Aim 1), while ordinal logistic regression estimated the association between pre-fracture antidepressant use hospital LOS (Aim 2), and Cox proportional hazards models evaluated pre-fracture antidepressant use and mortality (Aim 3). A sex-by-exposure interaction term was added to adjusted models to examine sex differences. Beneficiaries with depression and prior antidepressant use were 79 years of age, on average, and most were White females. Those with depression spent 11 fewer average DAH compared to counterparts without depression (incidence rate ratio [IRR]=0.92; 95% CI=0.91, 0.93; p<.0001), but this associated attenuated after adjusting for comorbidities. Beneficiaries with depression who used antidepressants before fracture had 8% higher odds of a shorter hospital LOS compared to non-users (odds ratio [OR]= 1.08; 95% CI=1.02, 1.14; p=0.01), and had a lower risk of 90-day (hazard ratio [HR]=0.84, 95% CI=0.76, 0.93, p=0.001) mortality compared to antidepressant non-users. No significant differences by sex were found in any analyses.
Results demonstrate the importance of recognizing the intersection of mental and physical health in post-hip fracture care, and considering patients’ entire, individual health profiles when making treatment decisions after fracture among older hip fracture survivors with depression.