Results
A total of 27 studies were included in the systematic review, including 10 studies on preoperative use, 4 on early postoperative use, and 13 on rescue use after insufficient weight loss or weight regain. Among them, 13 studies were included in efficacy meta-analyses. Preoperative use of GLP-1 receptor agonists improved preoperative weight loss, with a pooled SMD of 0.52 (95%CI: 0.25-0.79, I²=0%, P<0.05). However, when postoperative weight loss at 12 months was assessed using body weight at surgery as the baseline, the percentage of total body weight loss at 12 months was 2.85 percentage points lower in the preoperative medication group than in the non-medication group (95%CI: -4.35 to -1.36, I²=37.7%, P<0.05). Active addition of GLP-1 receptor agonists around 1 month after surgery increased the percentage of total body weight loss at 6 months by an additional 3.62 percentage points (95%CI: 1.88-5.37, I²=0%, P<0.05). Initiation of GLP-1 receptor agonists around 6 months after surgery resulted in an additional weight loss of 7.48 kg during subsequent follow-up compared with controls (95%CI: 5.35-9.60, I²=34.6%, P<0.05). For rescue therapy, four randomized controlled trials showed that GLP-1 receptor agonists resulted in an additional 10.30 percentage points of endpoint percentage weight loss compared with placebo or usual care (95%CI: 6.40-14.20, I²=89.2%, P<0.05). Regarding safety, among studies that clearly reported event numbers, the pooled incidences of nausea, constipation, diarrhea, and vomiting were 25.3%, 19.0%, 9.2%, and 8.6%, respectively. Serious adverse events were uncommon.
