Clinical Features and Outcomes of Iron Deficiency Anemia in Patients with Gastrectomy

Background: Iron deficiency anemia (IDA) is common in patients with partial or total gastrectomy; however, clinical features and appropriate therapy in these patients have not been well described. We compared clinical features and outcomes in IDA patients with and without gastrectomy.

Methods: We retrospectively analyzed clinical features at the time of diagnosis and response to iron therapy in IDA patients with partial or total gastrectomy (gastrectomy group) and in age- and gender-matched IDA patients without gastrectomy (control group) who were diagnosed between 2002 and 2010 at Chungnam National University Hospital.

Results: A total of 2,072 patients were diagnosed with IDA during the study period. Thirty-seven and 40 patients were enrolled in the gastrectomy and control groups, respectively. The median ages were 58.8 years (range, 19–84 years) and 52.7 years (range, 25–84 years), respectively. At initial presentation, the hemoglobin levels, mean corpuscular volume (MCV), mean corpuscular hemoglobin levels, mean corpuscular hemoglobin concentration, serum iron levels, total iron binding capacity, ferritin levels as well as endoscopic findings did not differ between the two groups. After 2 weeks, 6 weeks, and 3 months of oral iron therapy, hemoglobin levels were significantly lower in the gastrectomy group than in the control group (8.3 vs. 9.6 g/dL, P=0.012; 9.7 vs. 12.0 g/dL, P=0.000; 11.9 vs. 13.3 g/dL, P=0.016, respectively). After 2 weeks and 6 weeks of treatment, the increase in the hemoglobin level and that in the MCV were significantly slower in the gastrectomy group than in the control group (hemoglobin: 0.6 vs. 2.3 g/dL, P=0.000; 2.1 vs. 4.7 g/dL, P=0.000, respectively) (MCV: 2.6 vs. 6.2 fL, P=0.005; 7.2 vs. 12.7 fL, P=0.008). Parenteral iron was required in nine (23.4%) patients in the gastrectomy group, but not in the control group. The follow-up duration was much longer in the gastrectomy group (23.2 vs. 5.2 months, P=0.008), and 11 (29.7%) patients in this group needed long-term maintenance iron therapy. To normalize hemoglobin levels, longer treatment was required in the gastrectomy group (0.8 vs. 2.8 months, respectively; P=0.013).

Conclusion: The response to oral iron therapy in IDA patients with gastrectomy is slower than in those without gastrectomy. Parenteral iron therapy is needed in one-fourth of these patients to normalize hemoglobin levels.