Preoperative Hypoalbuminemia is Associated With an Increased Risk of Mortality in Patients With BMI ≥50 Undergoing Bariatric Surgery: Propensity Score Matching Analysis Using the 2015-2022 MBSAQIP Database

Abstract

Background

Hypoalbuminemia is associated with worse postoperative outcomes, but data is limited in the bariatric population. Patients with BMI ≥50 may represent a higher-risk group for malnutrition.

Methods

We analyzed MBSAQIP data (2015-2022) for patients undergoing sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB). Propensity score matching was used to control for 22 preoperative variables. We compared 30-day outcomes and bariatric-specific complications in patients with albumin <3.5 g/dL vs ≥3.5 g/dL across four groups: SG with BMI ≥50 (analysis 1), RYGB with BMI ≥50 (analysis 2), SG with BMI <50 (analysis 3), and RYGB with BMI <50 (analysis 4).

Results

Among 728,915 patients, matched cohorts in analyses 1 (n = 17,548), 2 (n = 9459), 3 (n = 16,025), and 4 (n = 6787) had similar preoperative characteristics. Hypoalbuminemia was associated with increased complications across all groups. In patients with BMI ≥50, hypoalbuminemia was significantly associated with increased mortality (SG 0.2% vs 0.1%, P = 0.011; RYGB 0.3% vs 0.1%, P < 0.001), unplanned ICU admission (SG 1.0% vs 0.7%, P = 0.020; RYGB 1.6% vs 1.2%, P = 0.034), and non-home discharge (SG 0.8% vs 0.5%, P < 0.001; RYGB 0.9% vs 0.6%, P = 0.009). These mortality differences were not observed in patients with BMI <50.

Conclusion

Hypoalbuminemia is associated with higher complications rates after bariatric surgery and increased mortality in patients with BMI ≥50. Preoperative nutritional optimization is strongly recommended in this high-risk group.