Long-term Outcome of the Dutch Common Channel Trial (DUCATI): Preservation of Superior Weight Loss Results Without Significant Malnutrition Side Effects.

Purpose: The optimal bowel limb lengths for laparoscopic Roux-en-Y gastric bypass (LRYGB) to maximize weight loss while minimizing nutritional deficiencies in severe obesity treatment remain a topic of debate. The multi-center Dutch Common Channel Trial (DUCATI) aims to compare the outcomes of a very long Roux Limb Roux-en-Y gastric bypass (VLRL-LRYGB) with a standard Roux-en-Y gastric bypass (S-LRYGB).

Methods: A total of 444 patients were randomly assigned in a 1:1, double-blind manner to undergo either VLRL-RYGB or S-LRYGB. Five-year follow-up data were assessed, concentrating on weight loss, obesity-related medical conditions, complications, re-operations, and malnutrition.

Results: Both groups had comparable total alimentary lengths (RL + CC). The VLRL-LRYGB group demonstrated significantly greater %TWL (32.2% vs. 28.6%, p = 0.002) and %EWL (81.2% vs. 70.3%, p = 0.002) at 5 years. Eight (3.6%) patients in the VLRL-LRYGB group versus 2 (0.9%) in the S-LRYGB group (p = 0.055) needed modification surgery for malabsorption. Suboptimal clinical response rate was significantly higher (22.0% vs. 8.3%) in S-LRYGB group. No significant differences for nutrient deficiencies in favor of the S-LRYGB group were found.

Conclusion: A 100-cm common channel with a relatively long Roux limb provides superior, sustainable weight loss over 5 years, without significantly increased rate of malabsorption-related re-operations. These results suggest that a longer Roux limb can still ensure adequate micronutrient uptake in the total alimentary tract. These findings should be considered in discussions regarding the optimal Roux-en-Y limb length for severe obesity treatment.