Predictors of Improved Physical Functioning after Bariatric Surgery

Eliza A Conaty, BS¹, Brittany Lapin, PhD¹, Stephen P Haggerty, MD¹, Woody Denham, MD¹, John G Linn, MD¹, Kristine Kuchta, MS¹, Zeeshan A Butt, PhD², Michael B Ujiki, MD¹. ¹NorthShore University HealthSystem, ²Northwestern University

INTRODUCTION: Several studies have shown that bariatric surgery improves physical functioning and lessens symptoms related to poor physical function. However, none exist which make use of a quality of life metric specific to surgical outcomes. We aimed to better assess patient quality of life after bariatric surgery, specifically as it relates to physical functioning, and elucidate potential predictors of improved or worsened symptoms.

METHODS AND PROCEDURES: Data was collected using a prospective bariatric surgical database at our institution. We included patients having undergone primary bariatric surgery at our site, and excluded those receiving revisional procedures. Quality of life data was captured via Surgical Outcomes Measurement System (SOMS) questionnaires administered preoperatively and postoperatively at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year. Questionnaire domains were specific to upper and lower extremity physical function symptoms within the most recent 7 days. Quality of life scores were analyzed with respect to preoperative diagnosis of musculoskeletal disease, musculoskeletal disease specific medication use, prior joint repair surgery, daily pain medication requirements, surgical interventions for physical functioning, weekly exercise, gender, age, and BMI.

RESULTS: From 2014 to 2016, 296 bariatric patients completed SOMS quality of life questionnaires specific to physical function. A statistical mixed effects model was used to analyze the data. Patients had significant improvement in both upper and lower physical function quality of life scores in the first year following bariatric surgery (p<0.01). Pre-existing musculoskeletal disease, physical function medication requirements, and activity limited by pain were all predictors of worse physical function quality of life scores over time (p<0.01, p<0.01). Pain medication taken for physical function was a predictor of worse upper physical function scores over time (p<0.02). Postoperative exercise correlated with improved upper and lower physical function scores over time (p=0.01, p=0.048). Higher postoperative BMI correlated with worse upper and lower physical function scores (p=0.06, p<0.01). A higher 6 month postoperative BMI predicted worse upper and lower physical function scores at 6 months and 1 year after surgery.

CONCLUSIONS: While pre-existing musculoskeletal conditions and medication requirements are predictors for worse physical functioning over time after bariatric surgery, postoperative weight loss correlates with improved physical function in both upper and lower extremities. Additionally, postoperative exercise supplements these improvements in physical functioning after bariatric surgery. Bariatric surgery, accompanied by successful postoperative weight loss and supplemented by excercise is an effective tool to improve patient quality of life with respect to physical function.