Secondary Bariatric Surgery-Does the Type of Index Procedure Affect Outcomes After Conversion?

ABSTRACT

BACKGROUND: Although revisions account for 17% of cases performed at bariatric centers of excellence, scarce data exists on whether index operation type influences outcomes after secondary operations. OBJECTIVE: We designed a study investigating the effect of primary procedure type on weight loss and perioperative complications after conversion bariatric surgery. SETTING: Tertiary Referral Hospital, USA. METHODS: We performed a retrospective review of patients undergoing conversion from sleeve gastrectomy (SG) or adjustable gastric band (AGB) to Roux-en-Y gastric bypass (RYGB) from 2009 to 2019. Post-operatively, we measured short- and medium-term complications and changes in body weight at various time points. Univariate and regression analyses were performed. RESULTS: Forty-two (SG) patients and 116 (AGB) patients underwent conversion to RYGB, most commonly for GERD (57.1%) in SG patients vs. weight regain (77.6%) in AGB patients. Mean pre-conversion BMI was 36.7 kg/m2 (SG) vs 43.8 kg/m2 (AGB). Mean time to conversion (months) was 52.9 (SG) vs 94.7 (AGB). Complication rate was 9.5% (SG) vs 6% (AGB) at 30 days (p = 0.48) and 31%(SG) vs 14.5% (AGB) (p = 0.02) at 2 years. Mean post conversion %TWL was 11.6% (SG) vs 24.6% (AGB) in patients with GERD/dysphagia (p = 0.014) and 20.7% (SG) vs 27.6% (AGB) in patients converted for weight-related reasons (p = 0.027) at 1 year. Overall mean %TWL was 13.2% (SG) vs 24.7% (AGB) at 2 years (p < 0.0035). CONCLUSION: After conversion to RYGB, patients with AGB experience better short- and medium-term weight loss than those with SG, even after accounting for conversion indications. SG to RYGB conversions have a higher resolution of reflux disease.