Body mass index and recovery of activities of daily living in older patients with femoral fracture: An analysis of a national inpatient database in Japan.

• Effects of BMI on ADL in older Asian patients with femoral fracture were examined. • Underweight was associated with poor recovery of ADL after femoral fracture. • Underweight patients had more complications and a lower rate of return to home. • Overweight/obesity may positively affect functional recovery after femoral fracture. To evaluate the effects of body mass index (BMI) on recovery of activities of daily living (ADL) in older Asian patients with femoral fracture registered in a nationwide inpatient database in Japan. We retrospectively analyzed data of patients aged ≥65 years with acute femoral fracture between April 2014 and November 2017 in the Diagnosis Procedure Combination database. Patients were classified into the following categories based on BMI (kg/m2): underweight (<18.5); normal weight (18.5–22.9); overweight (23–27.4); obese (≥27.5); and missing data. Demographic data included age, sex, type of fracture, comorbidities, and Barthel Index (BI). The primary outcome was BI at discharge and secondary outcomes were the overall complication rate and discharge to home. In total, data for 13,348 patients were extracted from the database, of whom 80.3 % were female. At discharge, underweight patients had lower BI than overweight or obese patients. In multivariable analysis, underweight and missing BMI data were associated with lower BI at discharge (partial regression coefficients −2.324 and −5.763, respectively). In contrast, overweight and obese were correlated with higher BI (3.080 and 5.732, respectively). Underweight was independently associated with a higher overall complication rate (odds ratio 1.195) and a lower rate of discharge to home (odds ratio 0.865). Underweight was associated with poorer performance in ADL, higher risk of complications, and lower rate of discharge to home in older Asian patients with femoral fracture. Overweight and obese had positive effects on ADL. [ABSTRACT FROM AUTHOR]