Enteral Vitamin B-12 Supplementation Is Effective For Improving Anemia In Patients Who Underwent Total Gastrectomy

Background: This study aimed to investigate the efficacy of enteral supplementation of vitamin B-12 for vitamin B-12 deficiency in patients who underwent total gastrectomy for gastric cancer. Methods: The study enrolled 133 patients who underwent total gastrectomy for gastric cancer at Kochi Medical School. Clinical data were obtained to investigate associations between vitamin B-12 supplementation and vitamin B-12 levels. Vitamin B-12 deficiency was defined as serum vitamin B-12 less than 200 pg/mL. Baseline characteristics and changes in hematological variables, including vitamin B-12 levels, were examined. Results: Vitamin B-12 deficiency was present in 71.4% of the 133 patients. Vitamin B-12 levels at 3, 6, and 12 months after enteral supplementation were 306 pg/mL, 294 pg/mL, and 367 pg/mL, respectively, which were all significantly higher than those before supplementation (p < 0.001 for all comparisons). The median red blood cell count at 3, 6, and 12 months after enteral supplementation were 380 x 10(4)/mm(3), 394 x 10(4)/mm(3), and 395 x 10(4)/mm(3), respectively, which were all significantly higher than those before supplementation (p = 0.020, p = 0.001, and p = 0.003, respectively). Vitamin B-12 levels at 3, 6, and 12 months after supplementation were significantly higher in patients supplemented enterally than those supplemented parenterally (p < 0.001 for all comparisons). Conclusions: Vitamin B-12 deficiency was found in 71.4% of postoperative patients who underwent total gastrectomy for gastric cancer, and enteral vitamin B-12 supplements might be effective to improve anemia in these patients.