Prehabilitation for patients undergoing metabolic/bariatric surgery: a retrospective cohort study using propensity score matching.

Abstract

Multimodal prehabilitation improves outcomes in colorectal surgery, but its effectiveness and cost-effectiveness before metabolic and bariatric surgery are unknown. To evaluate the effectiveness and cost-effectiveness of a 6-week multimodal prehabilitation programme compared with standard preintervention education in patients undergoing bariatric surgery. Propensity score matched cohort observational study at Shanghai Tenth People's Hospital, China, January 2022 to January 2025. Sixty prehabilitation patients were matched 1:1 to 60 controls from 254 standard care candidates using nearest-neighbour matching on the logit of the propensity score. Follow-up was 12 months. A 6-week programme of supervised exercise, nutritional counselling, and psychological support vs 2 standard preoperative counselling sessions. All patients underwent Roux-en-Y gastric bypass or sleeve gastrectomy. Total weight loss at 12 months. Secondary outcomes included body composition, metabolic parameters, functional capacity, patient-reported outcomes, safety, and healthcare costs. Among 120 matched patients (mean [SD] age, 32.6 [5.2] years; 65.8% male; mean body mass index [BMI], 38.2 [3.2] kg/m2), total weight loss at 12 months did not differ between groups (23.7 [5.1] vs 23.4 [2.7] kg; difference, 0.3 kg; 95% CI, -1.3 to 1.8; p = 0.75). At 3 months, prehabilitation showed significantly greater weight loss (adjusted β = 2.85 kg; 95% CI, 1.77 to 3.93; p < 0.001), lower body fat, lower diastolic blood pressure, and higher Short Form-36 (SF-36) mental scores. All differences were attenuated by 6 months. No serious adverse events occurred. Total costs were modestly higher in the prehabilitation group (mean, ¥84 843 vs ¥78 051), a difference attributable almost entirely to the prehabilitation programme itself; because the incremental effect on weight loss at 12 months was not statistically significant, a meaningful incremental cost-effectiveness ratio could not be estimated. A 6-week multimodal prehabilitation programme accelerated early postoperative weight loss and improved short-term functional outcomes but did not improve total weight loss at 12 months. Because prehabilitation added cost without a demonstrable difference in 12-month weight loss, a cost-effectiveness advantage could not be established. The dominant metabolic effects of bariatric surgery appear to override the incremental gains of preoperative conditioning over time.