Woo SH, et al. - In an older population, authors assessed the correlation between body mass index (BMI) and mortality after hip arthroplasty. They included 3,627 older patients who had hip arthroplasty from 2010 to 2013. Cox regression analysis was used to evaluate the correlation between BMI and mortality following hip arthroplasty. Findings suggested an ink between being underweight and an increased risk of mortality following hip arthroplasty. Also, they noted an association of obesity with increased mortality within 30 days after hip arthroplasty.