Factors associated with weight regain post-bariatric surgery: a systematic review

To systematically review the literature to assess the incidence and risk factors of weight regain (WR) after bariatric surgery. Bariatric surgery is the most effective intervention for sustained weight loss of morbidly obese patients, but WR remains a concern.

A PRISMA compliant systematic literature review was performed using the PubMed database, Embase and the Cochrane Library in July of 2019. Studies that reported ≥ 10% WR after Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) were included. The Newcastle-Ottawa scale (NOS) was used for assessing study quality.

Out of 2915 retrieved abstracts, 272 full papers were reviewed, and 32 studies included (25 of high and 7 of fair quality) reporting weight outcomes on 7391 RYGB and 5872 SG patients. 17.6% (95% CI 16.9-18.3) had a WR ≥ 10%. Risk factors related with WR fell into 5 categories, namely anatomical, genetic, dietary, psychiatric, and temporal. Specifically, gastrojejunal stoma diameter, gastric volume following sleeve, anxiety, time after surgery, sweet consumption, emotional eating, portion size, food urges, binge eating, loss of control/disinhibition when eating, and genetics have been positively associated with WR while postprandial GLP-1, eagerness to change physical activity habits, self-esteem, social support, fruit and zinc consumption, HDL, quality of life have been negatively associated.

At least 1 in 6 patients after bariatric surgery had ≥ 10% WR. This review identified several factors related to WR that can be used to counsel patients preoperatively and direct postoperative strategies that minimize WR risk.