http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3354399/
first, let's play 'spot the methodological flaws'. in the abstract, one stands out to me. any thoughts?Background: Vitamin B12 (Cobalamin) deficiency can result in some clinical and paraclinical characteristics similar to what is seen in multiple sclerosis (MS) patients. This study aimed to evaluate the controversial association between vitamin B12 deficiency and MS.
Methods: We measured serum vitamin B12 in 60 patients with MS and 38 healthy controls. Clinical disability was evaluated according to the Extended Disability Status Scale (EDSS). Serum B12 concentration was measured with Radioimmunoassay Dual Isotope method. The cutoff value for low serum vitamin B12 concentrations was 75 pg/mL. [jl edit: interesting - my lab must have used this assay too; my cleanest b12 test from '06 came back with the result "less than 75"] Patients were in remission at the time of blood draw.
Results: There were 13 (21.6%) MS patients and 10 (26.3%) controls with low serum B12 concentration with no significant difference between the groups; P>0.05. The mean serum vitamin B12 concentration in MS patients (108.9±45.3 pg/mL) was not significantly different compared with controls (98.9±44.4 pg/mL); P=0.284. Likewise, there was no correlation between the concentration of serum vitamin B12 and disease’ age of onset, duration, subtypes, or disability status.
Conclusions: In contrast to some previous reports, our findings did not support any association between B12 deficiency and MS.
here's the study data, showing patients with higher levels than controls: http://www.ncbi.nlm.nih.gov/pmc/article ... /table/T1/
http://www.sciencedirect.com/science/ar ... 6808002622
they're all pretty bad though, across the board.
if i had been in this study in 2005, i would have been in the control group with low b12 and no ms. by 2006, i would be in the patient group with low b12 and ms. there *is* a b12 - ms connection. it's just not as simple as b12 alone.
another study:
Serum vitamin B12, folate, and homocysteine levels and their association with clinical and electrophysiological parameters in multiple sclerosis
http://www.sciencedirect.com/science/ar ... 6808002622
Table 2We aimed to evaluate serum vitamin B12, folate, homocysteine, mean corpuscular volume (MCV), hemoglobin (Hb), and hematocrit (Hct) levels in patients with MS. ... These parameters were evaluated in 35 patients during an acute attack and compared to data collected from 30 healthy individuals (control subjects).
Vitamin B12, folate, homocysteine, Hb, and Hct levels and MCV in patients with
multiple sclerosis and healthy control subjects
.............................Patients with MS..............Control group
Vitamin B12 (pg/mL)....221.26 ± 72.75...........257.43 ± 105.67
butNo statistically significant differences (mean ± SD) were observed for vitamin B12, folate, or homocysteine levels
Subjects who exhibited prolonged (>116 ms) VEP latencies had lower vitamin B12 levels compared to normal subjects (212.22 ± 66.72 pg/mL vs. 251.75 ± 88.30 pg/mL, respectively). Patients who exhibited posterior tibial SEP P1 latencies longer than 42.1 ms also had lower vitamin B12 levels compared to normal subjects (221.95 ± 69.92 pg/mL vs. 244.57 ± 97.84 pg/mL). Similarly, subjects who exhibited prolonged (> 63 ms) posterior tibial SEP P2 latencies had lower vitamin B12 levels compared to normal subjects (214.67 ± 63.76 pg/mL vs. 246.87 ± 98.06 pg/mL)
grr using what standard :S moving on..We found a significant association between MS and vitamin B12 deficiency, and therefore suggest that all patients with MS should be screened for vitamin B12 deficiency.
just looking for general healthy controls serum levels now... found this which sidetracked me neatly:
Folate, vitamin B12, and neuropsychiatric disorders.
http://www.lef.org/protocols/abstracts/ ... ote]Folate and vitamin B12 are required both in the methylation of homocysteine to methionine and in the synthesis of S-adenosylmethionine. S-adenosylmethionine is involved in numerous methylation reactions involving proteins, phospholipids, DNA, and neurotransmitter metabolism. Both folate and vitamin B12 deficiency may cause similar neurologic and psychiatric disturbances including depression, dementia, and a demyelinating myelopathy. A current theory proposes that a defect in methylation processes is central to the biochemical basis of the neuropsychiatry of these vitamin deficiencies.[/quote]
i'm on board with the methylation defect.. went looking for other players
Effect of zinc deficiency on methionine metabolism, methylation reactions and protein synthesis in isolated perfused rat liver.
http://europepmc.org/abstract/MED/3968590
will continue reviewing the literature, to establish an actual optimal serum cobalamin range seen in healthy controls across multiple studies.