Racial differences in weight loss, hemoglobin A1C, and blood lipid profiles after Roux-en-Y gastric bypass surgery

Surg Obes Relat Dis. 2016 Aug;12(7):1329-1336. doi: 10.1016/j.soard.2015.12.028. Epub 2016 Jan 6.

Abstract

Background: It is known that African American (AA) patients with obesity achieve less weight loss after Roux-en-Y gastric bypass surgery (RYGB) than their Caucasian (CA) counterparts. However, it is unclear how these differences in weight loss are reflected in clinical outcomes.

Objectives: To determine the effects of RYGB on hemoglobin A1c (A1c) and blood lipids in relationship to the variability in weight loss outcomes in a racially mixed patient population.

Setting: University medical center.

Methods: Retrospective analysis of clinical data from electronic medical records of CA, AA, and Hispanic American (HA) patients undergoing RYGB.

Results: We used 2-way cluster analysis and identified 4 distinct weight loss×race clusters. CA patients separated into 2 clusters (45.5% and 28.2% weight loss, respectively), whereas, AA and HA patients separated into 1 cluster each (33.2% and 34.4% weight loss, respectively). Factors that significantly affected weight loss were race, age, gender, and physical activity as well as presence of hypertension and degenerative joint disease. Although all clusters had significant improvements in blood lipids, HA had an increase in total cholesterol (Total-c) and low-density lipoprotein cholesterol (LDL-c) at 2 years after surgery. All clusters had significant decreases in A1c in the first year. At 2 years after RYGB, A1c levels remained stable in CA and HA; however, AA had a significant increase. These racial differences in A1c could not be explained by the smaller weight loss in AA patients.

Conclusion: Race is an important factor in the clinical outcomes of RYGB, especially in regard to diabetes control; however, its effect is not completely understood.

Keywords: Bariatric surgery; Black; Blood lipids; Diabetes; Hemoglobin A(1c); Weight loss.

MeSH terms

  • Adult
  • Age Factors
  • Analysis of Variance
  • Black or African American / ethnology
  • Cluster Analysis
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / ethnology
  • Female
  • Gastric Bypass*
  • Glycated Hemoglobin / metabolism
  • Hispanic or Latino
  • Humans
  • Lipids / blood*
  • Male
  • Middle Aged
  • Obesity / blood
  • Obesity / ethnology
  • Obesity / surgery
  • Postoperative Care
  • Racial Groups / ethnology*
  • Retrospective Studies
  • Weight Loss / ethnology*
  • White People / ethnology

Substances

  • Glycated Hemoglobin A
  • Lipids