Low vitamin B12 status and less response to vitamin B12 treatment in Chilean B12‐deficient elderly with high serum folate (135.8)

Abstract

Few data are available on the relationship between folate and B12 status in B12 deficient, but asymptomatic, free-living populations. The objective was to determine the effect of a single i.m. dose of 10,000 µg cbl on B12 status in B12 deficient subjects with high (>45.3 nmol/L) and normal (蠄45.3 nmol/L) serum folate. 51 elderly participants (73 ± 2.5y, 49% women) with sB12 <148 pmol/L received treatment. sB12, tHcy, MMA, holo-TC and folate status biomarkers were assessed 4 mo after treatment. B12 status was defined based on Fedosov’s criterion: w=log_10 [(holoTC*sB12)/(MMA*tHcy)-age factor)]. At baseline (Fig 1), subjects with high sfolate (n=14) presented low B12 status (w= -3.3 ± 0.2), as compared to subjects with normal folate levels (n=37, w= -2.9 ± 0.5) (p<0.001). B12 status improved in both groups after treatment (p<0.001). However, subjects with high folate status at baseline remained severely deficient (w= -2.7 ± 0.7). On the other hand, participants with normal folate values at baseline were classified as moderately deficient (w= -1.8 ± 1.1) after treatment. B12 deficiency, as defined by Fedosov’s criteria, was highly prevalent both at baseline and after treatment. Chilean B12 deficient older people with high sfolate presented low B12 status and less response to B12 treatment as compared to those B12 deficient with normal folate status. Figure 1. Vitamin B12 status before and after treatment depending on folate status. Grant Funding Source: Funding: Chilean FONDECYT #10700592