Change in Physical Activity Prior to Bariatric Surgery does not Predict Post-Surgery Weight Loss

Abstract

Few studies have examined if change in moderate-to-vigorous physical activity (MVPA) prior to bariatric surgery is associated with post-surgery weight loss. PURPOSE: To examine if change in pre-surgery MVPA resulting from 6-months of usual care (UC) or a pre-surgical behavioral lifestyle intervention (BLI) is associated with weight change following bariatric surgery. METHODS: Data from adults with severe obesity (N=97; BMI 47±5.9 kg/m2) electing to undergo either Roux-en-Y gastric bypass (RYGB) or laparoscopic adjustable gastric banding (LAGB) were used for this study. These subjects are a subset from a larger trial who provided complete physical activity and weight data, were randomized to UC or BLI for 6 months prior to their bariatric surgery procedure, and not lost to follow-up. UC received physician recommendations for diet and activity. BLI participated in a behavioral weight management program that included 12 in-person sessions and 12 telephone contacts. BLI was prescribed a reduced energy diet (1200–1400 kcal/day) and to increase MVPA to 30 minutes on 5 days/wk. MVPA was measured prior to and following the pre-surgical period, with MVPA defined as min/wk from activity bouts ≥10 minutes in duration at ≥3 METS. Weight was assessed pre- and post-UC or BLI, and 6, 12 and 24 months post-surgery. RESULTS: After controlling for weight change pre-surgery, change in MVPA prior to surgery in those receiving UC was not significantly associated with 24 month weight change post-surgery for LABG (r=0.40, p=0.13) or RYGB (r=0.09, p=0.74). The association between change in MVPA prior to surgery and 24 month loss post-surgery in those receiving BLI was 0.42 (p=0.09) in LAGB and 0.07 (p=0.80) in RYGB. CONCLUSION: Pre-surgery change in MVPA was not predictive of post-surgery weight loss in patients undergoing either RYGB or LAGB. Whether pre-surgery MVPA is associated with other health benefits post-surgery warrants additional investigation. Supported by the NIH (R01 DK077102)