J. H. Fieber1, P. Dowzicky1, C. Wirtalla1, N. N. Williams1, D. T. Dempsey1, R. R. Kelz1 1University Of Pennsylvania,Department Of Surgery,Philadelphia, PA, USA
Introduction: Hypoalbuminemia is a known risk factor for poor outcomes after elective general surgery. Many obese patients concurrently suffer from modest to severe malnutrition. We seek to evaluate the impact of hypoalbuminemia on surgical outcomes in obese patients undergoing elective bariatric surgical procedures.
Methods: The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program for 2015 was queried for adult patients with body mass index [BMI] ≥ 35 undergoing bariatric surgery. Revision procedures and patients missing albumin values were excluded. The analysis was controlled for 12 potentially significant confounders. Low albumin was defined as albumin <3.5, <3.0, and <2.5. Independent logistic models were developed to estimate the adjusted odds of death/serious morbidity (DSM) or readmissions associated with hypoalbuminemia. A test for the interaction between 10% weight loss, measured in kilograms, and hypoalbuminemia was performed. Bonferroni correction was used to correct for multiplicity using 0.006 as the threshold for significance.
Results: A total of 106,577 patients were included in the study with a mean age of 44 years-old (IQ: 36-53), 78.9% female, and 74.8% White. By procedure, sleeve gastrectomy was most common (65%), followed by gastric bypass procedure (30.3%), laparoscopic band procedure (3%), and other bariatric procedures (1%). The majority of patients had a BMI of 40-49.9 (52.1%). Among patients with low albumin, 6.3% (n=6,647) had albumin <3.5, 0.3% (n=350) had albumin <3, and 0.1% (n=94) had albumin <2.5. Patients with albumin <3.5 were 45% (OR: 1.45, CI: 1.25-1.67, p<0.001) more likely to have DSM following bariatric surgery. There was increasing likelihood of DSM with albumin <3 and albumin <2.5 [Table 1]. Patients with albumin <3.5 were 21% (OR: 1.21, CI: 1.09-1.35) more likely to require readmission. There was a significant interaction between 10% weight loss and low albumin for DSM when albumin was <3.0 (OR: 5.10, CI: 1.71-15.22, p=0.003).
Conclusion: Obesity is not uniformly associated with a well-nourished state. More than 5% of patients undergoing bariatric surgery have hypoalbuminemia. Preoperative albumin is an important and modifiable risk factor for postoperative complications following bariatric surgery. Weight loss of 10% combined with hypoalbuminemia is synergistic for high complication rates and should be investigated before proceeding with elective bariatric surgery.
