Ring-Augmented Versus Standard Roux-en-Y Gastric Bypass: A Systematic Review and Meta-Analysis of Randomized Controlled Trials with GRADE Assessment

The benefit-risk profile of prophylactic non-adjustable ring augmentation added to primary Roux-en-Y gastric bypass (ring-augmented RYGB) remains uncertain. We conducted a PRISMA 2020-reported systematic review and random-effects meta-analysis of prospective randomized trials comparing ring-augmented (rRYGB) versus standard non-ring-augmented RYGB (nrRYGB) in adults. PubMed/MEDLINE, Web of Science, Scopus, and CENTRAL were searched from inception through December 2025. Five randomized trials including 920 patients from the USA, Mexico, Brazil, the Netherlands, and Egypt were included. Rings were typically placed 2-3 cm above the gastrojejunostomy, most commonly with a 6.5 cm circumference. rRYGB did not improve % excess weight loss (%EWL) at 6 months (MD 1.99, 95% CI - 1.15 to 5.13; moderate-certainty evidence) but was associated with a modest increase in %EWL at 12 months (MD 3.27, 95% CI 0.55 to 5.98; low-certainty evidence), 24 months (MD 2.72, 95% CI 0.59 to 4.86; moderate-certainty evidence), and 36 months (MD 4.10, 95% CI 1.40 to 6.79; moderate-certainty evidence). At 60 months, %EWL was not significantly different (MD 2.64, 95% CI - 3.18 to 8.47; very low-certainty evidence); however, this estimate was based on only 173 patients and the prediction interval spanned - 35 to + 40% points, limiting the interpretability of the pooled result at this timepoint. Overall complications were similar (RR 1.12, 95% CI 0.87 to 1.45; moderate-certainty evidence), but vomiting was more frequent with augmentation (RR 2.80, 95% CI 1.71 to 4.59; moderate-certainty evidence) and a preliminary signal of higher re-operation was observed (RR 1.69, 95% CI 1.00 to 2.86; moderate-certainty evidence), although trial sequential analysis indicated that the required information size had not been reached. Hypertension, dyslipidemia, and diabetes resolution did not differ materially between groups, and overall quality of life was generally comparable; one trial reported worse GERD-HRQL at 3 years with augmentation. rRYGB yields a modest mid-term %EWL advantage up to 3 years, of about 3 to 4% points, without a clear 5-year benefit, while increasing vomiting risk and showing a preliminary signal of higher re-operation, with no evident comorbidity or overall quality-of-life advantage. KEY POINTS: • Weight loss: Similar early outcomes, but rRYGB shows a modest %EWL advantage at 12-36 months, not clearly sustained by 60 months. • Harms: Vomiting is about 3× more frequent with augmentation; a preliminary signal suggests higher reoperation versus standard RYGB, but the required information size has not been reached. • Metabolic effects: Comorbidity resolution (diabetes, hypertension, dyslipidemia) and overall QoL are broadly similar between approaches. • Clinical takeaway: Current randomized evidence does not define a validated subgroup most likely to benefit from ring augmentation; therefore, any selective use should be regarded as expert opinion rather than an evidence-based recommendation, and must be weighed against intolerance and device-related interventions.