Comparison of Eastern and Western patients undergoing bariatric surgery at two US and Korean institutions: a retrospective analysis of differing bariatric patient populations.

backgroundCurrently, there are differences in both demographics and indications for bariatric surgery between Eastern and Western countries. We compared postoperative outcomes between Korean and American bariatric programs in order to assess how bariatric surgery differently affects these populations.

methodsWe enrolled 540 patients who underwent bariatric surgery at University of California, Los Angeles (UCLA) and 85 patients who underwent surgery at Kosin University Gospel Hospital (KUGH) between January 2019 and December 2020. We compared demographics, complications, weight loss, and metabolic parameters between these groups.

resultsThere was a difference in age between the UCLA and KUGH patient groups (44.3 years vs 37.6 years, P < 0.01). Frequencies of T2DM and OSA were also different (4.2% vs 50.6%, 34.1% vs 85.9% P < 0.01. Length of hospital stay varied (1.55 days vs 6.68 days, P < 0.01), but there was no difference in operating time and complications. There was no difference in percent of excess weight loss between the two groups at 6 months (29.7 vs 33.8, P = 0.13). Hepatic steatosis index (HSI) was higher in the UCLA group both before (54.2 vs 51.5, P < 0.01) and after (44.4 vs 40.0, P = 0.02) surgery. LSG was the most frequently performed operation, and robotic surgery and revisions were performed only in the UCLA program.

conclusionThere were differences in age, BMI, length of stay, and choice of operation between Korean and American bariatric patients. Also, there were differences in the degree of fatty liver disease using HSI and liver enzymes before and after surgery. There was no significant differences in operation time and complications. These findings suggest differences in bariatric practices and reactions to bariatric surgery in Eastern and Western settings.