Anemia Status Changes Among Patients With Obesity Following Bariatric Surgery

Objective This study aims to investigate trends in anemia severity among patients with pre-existing anemia who underwent bariatric surgery due to obesity. It also examines how different bariatric surgery techniques impact anemia outcomes. Methods This prospective study included 280 patients aged 18 to 65 with obesity who underwent bariatric surgery. The patients were categorized into three groups based on the type of surgery: sleeve gastrectomy, one-anastomosis gastric bypass, and Roux-en-Y gastric bypass. Anemia severity was evaluated over a 12-month follow-up period. Chi-square tests were used to assess the homogeneity of baseline factors among the groups, and McNemar tests along with generalized estimating equations were used to compare anemia outcomes. Results Before surgery, the rates of moderate anemia across the three surgical groups ranged from 18.2% to 22.4%, with no cases of severe anemia observed. There was no significant difference among the groups (p=0.949). During the 12-month follow-up, the odds ratio for reducing anemia severity in the sleeve gastrectomy and Roux-en-Y gastric bypass groups were 2.13 and 1.91, respectively, compared to the one-anastomosis gastric bypass group. Additionally, the odds ratio for reducing anemia severity in patients with hypothyroidism was 1.84 compared to those without hypothyroidism. Conclusion The choice of bariatric surgery technique significantly affects anemia outcomes, with sleeve gastrectomy showing a higher success rate in reducing anemia severity. The role of hypothyroidism in anemia management also appears to be significant.