Comparison Between Different Intramuscular Vitamin B12 Supplementation Regimes: a Retrospective Matched Cohort Study.

BACKGROUND: The incidence of vitamin B12 deficiency after bariatric surgery can range from 26 to 70 %. There is no consensus on optimal vitamin B12 supplementation in postbariatric patients. The objective of this study was to compare three different regimes. METHODS: In this retrospective matched cohort study, we included 63 patients with methylmalonic acid (MMA) levels ≥300 nmol/L. Group A (n = 21) received 6 intramuscular (im) vitamin B12 injections including a loading dose, group B (n = 21) received 3 im vitamin B12 injections without loading dose and group C (n = 21) received no im vitamin B12 injections. RESULTS: The total post-bariatric patient population consisted of 14 males (22.2 %) and 49 women (77.8 %) with a mean current body mass index of 30.6 ± 8.0 kg/m2. There was no significant difference in vitamin B12 and MMA levels between 3 groups at baseline. There was a significant difference in follow-up vitamin B12 levels of group A compared to group B (p = 0.02) and group A compared to group C (p = 0.03). In the follow-up results, there is also a significant decrease in MMA levels of group A compared to group B (p = 0.02), group A compared to group C (p < 0.001), and group B compared to group C (p < 0.01). CONCLUSIONS: In this study, a shorter injection regime is probably not sufficient to treat a vitamin B12 deficiency. An injection regime with 6 injections recovered all vitamin B12 deficiencies biochemically. MMA levels cannot recover spontaneously over time without additional im injection regime.

Improving Bariatric Patient Aftercare Outcome by Improved Detection of a Functional Vitamin B12 Deficiency.

BACKGROUND: Vitamin B12 deficiency is common after bariatric surgery. Vitamin B12 is a poor predictor of functional vitamin B12 status, since deficiencies might even occur within the reference limits. Therefore, vitamin B12 deficiencies with serum vitamin B12 levels are between 140 and 200 pmol/L remain undetected. Methylmalonic acid (MMA), however, will detect these deficiencies as accumulates due to functional intracellular vitamin B12 deficiencies. MMA is a relative expensive analysis and is therefore not generally available. To lower the costs, we only request MMA when vitamin B12 levels are between these levels. As a result, more biochemical deficiencies are found. However, it was not known whether bariatric patients with vitamin B12 levels between 140 and 200 pmol/L would benefit from supplementation. METHOD: Bariatric patients with vitamin B12 levels between 140 and 200 pmol/L with (n = 45) and without (n = 45) intramuscular hydroxocobalamin injections were compared. RESULTS: Treated patients showed a significant increase of vitamin B12 levels (P < 0.001) and a significant decrease in MMA levels (P < 0.001). Biochemical improvement occurs in both patients with and without clinical symptoms. The control group showed a significant increase of MMA levels (P < 0.001). To examine whether biochemical benefits of vitamin B12 supplementation are correlated with clinical improvement, patient records were checked for complaints. Complaints were disappeared after treatment, while no improvement was seen in untreated patients. CONCLUSION: This study shows that all bariatric patients with vitamin B12 levels between 140 and 200 pmol/L benefit clinical and biochemical from vitamin B12 supplementation, regardless the MMA levels.