Oral vitamin B-12 may replace hydroxocobalamin injections in treating RYGB patients
Oral vitamin B-12 supplementation yields similar efficacy to that of hydroxocobalamin injections, according to a recent study. This suggests that oral supplementation can be used to replace hydroxocobalamin injections in the treatment of Roux-en-Y gastric bypass (RYGB) patients with low values of serum vitamin B-12.
The investigators conducted a randomized controlled trial of RYGB patients with subnormal serum B-12 concentrations. One group (IM B-12) received bimonthly intramuscular hydroxocobalamin injections (2,000 µg as loading dose and 1,000 µg at follow-up) for 6 months. The other group (oral B-12) received daily doses of oral methylcobalamin (1,000 µg).
The investigators determined serum vitamin B-12 at baseline (T0) and at 2 (T1), 4 (T2) and 6 months (T3) after the start of treatment. They also measured concentrations of the secondary markers methylmalonic acid (MMA) and homocysteine (Hcy) at T0 and T3.
A total of 50 patients were randomly assigned to either IM B-12 (n=27) or oral B-12 (n=23). The respective median vitamin B-12 concentrations at T0 were 175 pmol/L (range, 114–196 pmol/L) and 167 pmol/L (range, 129–199 pmol/L).
Vitamin B-12 returned to normal levels in all participants, and no significant between-group difference was seen in vitamin B-12.
Both IM B-12 and oral B-12 groups showed significantly lower MMA (p<0.001 and p<0.001, respectively) and Hcy (p=0.03 and p=0.045, respectively) concentrations after 6 months. There was no significant between-group difference for both MMA (p=0.53) and Hcy (p=0.79) at 6 months.
Patients often develop a vitamin B-12 deficiency following RYGB, according to the investigators.