Efficacy of Long-Term Oral Vitamin B12 Supplementation after Total Gastrectomy: Results from a Prospective Study.

BACKGROUND/OBJECTIVES: Vitamin B12 (VB12) deficiency is a common complication after total gastrectomy which may be associated with megaloblastic anemia and potentially irreversible neurologic symptoms. Intramuscular supplementation of VB12 has been considered the standard treatment, although it is associated with high costs and patient discomfort.

PATIENTS/METHODS: We performed a prospective uncontrolled study (ACTRN12614000107628) in order to evaluate the clinical and laboratory efficacy of long-term oral VB12 supplementation in patients submitted to total gastrectomy. All patients received daily oral VB12 (1 mg/day) and were evaluated every 3 months (clinical and laboratory evaluation: hemoglobin, VB12, total iron, ferritin, and folate).

RESULTS: A total of 26 patients were included with a mean age of 64 years (29-79). Patients were included with a mean period of 65 months (3-309) after total gastrectomy. At inclusion time, 17/26 patients were under intramuscular VB12, and 9 had not started supplementation yet. There were normal serum VB12 levels in 25/26 patients (mean VB12 serum levels: 657 pg/mL). The mean follow-up period was 20 (8.5-28) months. During follow-up, all patients had normal VB12 levels and there was no need for intramuscular supplementation. The patient with low VB12 levels had an increase to adequate levels, which remained stable. There were no differences with statistical significance among VB12 levels at 6 (867 pg/mL), 12 (1,008 pg/mL), 18 (1,018 pg/mL), and 24 (1,061 pg/mL) months. Iron and folate supplementation was necessary in 21 and 7 patients, respectively.

CONCLUSIONS: Oral VB12 supplementation is effective and safe in patients who underwent total gastrectomy and should be considered the preferential form of supplementation.