Background
The ring-augmented Roux-en-Y gastric bypass (raRYGB) has been reported to result in higher long-term weight loss compared to regular Roux-en-Y gastric bypass (RYGB). However, the type of ring used varied within studies, leading to heterogeneity in reported results. Therefore, this study compares the 5-year results of RYGB with and without ring augmentation using a specific prefabricated gastric ring.

Methods
All consecutive patients from a single center who received primary raRYGB between June 1, 2016, and May 31, 2018, with complete 5-year follow-up data were included and compared to a propensity score matched cohort receiving RYGB in the same period from the Dutch Audit for Treatment of Obesity. To ensure fair effect estimation of placing a ring, only RYGB procedures with alimentary and biliopancreatic limb lengths similar to those of the raRYGB were considered eligible. The primary outcome was percentage total weight loss (%TWL). Secondary outcomes included recurrent weight gain (RWG), obesity complication improvement, and complications.

Results
In total, 592 matched patients were analyzed. raRYGB was associated with higher %TWL at 5 years (31.5% versus 28.0%, β = 3.59, 95% CI [2.09–5.09], p < 0.01) and lower odds on RWG (odds ratio = 0.56, 95% CI [0.38–0.83], p < 0.01). Improvement of obesity complications and short-term complication rates were comparable in both groups. After 5 years, 13 patients (4%) had experienced ring-related complications needing reoperation.

Conclusions
At 5 years, raRYGB was associated with higher %TWL and lower odds on RWG. The occurrence of ring-related complications was limited.

For author Perla J. Marang-van de Mheen, the name tagging in the XML is incorrect. The author given name should be “Perla J.”, and the author family name should be “Marang-van de Mheen”.