Association between preoperative serum albumin levels with risk of death and postoperative complications after bariatric surgery: a retrospective cohort study.

ABSTRACT

BACKGROUND: Hypoalbuminemia is common among individuals with obesity who qualify for bariatric surgery, but its relevance to clinical outcomes after bariatric surgery remains to be established. OBJECTIVES: To examine the association of preoperative serum albumin with 30-day postoperative outcomes. SETTING: Data from the 2015-2019 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program Participant Use Files were used. METHODS: Preoperative serum albumin level was categorized as hypoalbuminemia (<3.5 g/dL), and normoalbuminemia (3.5-5.5 g/dL) among patients who underwent bariatric surgery. Multivariate logistic regression models were used to determine the association of preoperative hypoalbuminemia with 30-day postoperative mortality and other co-morbid outcomes. RESULTS: Among 633,011 adult patients, 85.1% were women and the mean (standard deviation) age was 44.8 (12.0) years. The prevalence of hypoalbuminemia was 6.13% (n = 38,792). After adjustment for procedure type and demographic, lifestyle, and co-morbidity covariates, the odds ratio (OR) (95% confidence interval [CI]) for mortality was 1.42 (1.10, 1.82) for hypoalbuminemia. For all other outcomes, the ORs (95% CIs) for hypoalbuminemia ranged from 1.03 (.67-1.60) for cardiac arrest requiring CPR to 2.32 (1.66-3.25) for failure to be discharged by day 30. The ORs for several associations were higher for severe hypoalbuminemia than marginal hypoalbuminemia. CONCLUSION: Preoperative hypoalbuminemia was associated with several negative 30-day postoperative bariatric surgery outcomes and tended to be worse for severe hypoalbuminemia compared with marginal hypoalbuminemia. These findings suggest that serum albumin may be a useful biomarker to screen for negative bariatric surgery outcomes.