I was searching on "Google Scholar", a search engine for research databases, and came across a couple things I thought might be of interest to some of the people here.
First, I stumbled across something called "vitamin B12 deficiency neurological syndrome (VBDNS)". I have seen mention made of, and personally experienced, "brain fog", difficulty with recalling words, names, etc that are well-known to me, and similar symptoms indicating loss of cognitive functioning, but didn't realize that neuropsychological testing had demonstrated consistent loss of cognitive functioning in some people with B12 deficiency. VBDNS might be a productive search term for some of the people on this forum.
Second, I came across a quite recent article on assessment of B12 deficiency. I read some of it, but it will be a long time before I finish it. So even though I have not personally evaluated the article for accuracy, usefulness, etc., I thought I would post the link here in case others might be interested in the article. Please feel free to make your thoughts known if you find that the article is misleading or otherwise should not be trusted
I went through a long period when I would be reading at a built-in desk in the kitchen and suddenly didn't know where I was, until I looked around. It's scary because I didn't know what caused it and didn't know how far it would progress. Since I have been injecting, there are fewer such instances, but they still occur sometimes.
I had the disorientation issue when I was driving a few times - suddenly blanked on where I was going and where I was. Couldn't think of how to get home. I knew I was in my own city but couldn't recognize anything. I stopped driving after that!
Hadn't heard of VBDNS before.
Thanks for the link, will study it when I have some time. Looks very interesting!
It sounds similar, but I think in B12D we don't have trouble remembering the event (so we do form memories), and it lasts much shorter than 24h, at least in the stories I've read. But since it describes a condition not a disease, there may very well be some overlap with B12D.
My wife suffers from TGA. None of her events have lasted 24hrs. The longest was the first which was about 6hrs from start to finish. 2-4 hrs is more normal for her and sometimes they never quite kick in completely leaving her more vague than anything. She does have a clinical diagnosis of TGA. She also suffers from low B12 and we have questioned if there is a link of some sort as when her B12 is higher in range through self injecting, as I do, the TGA does seem to be less severe. I cannot state for sure tho, just how it seems to us.
I see. Despite not knowing any other history and not being a medic myself, I would say there can definitely be a link. Cognitive decline in general is a well known side effect of B12D. Since it's considered neurological, she should really be getting alternate day injections "until no further improvement".
There are some of us whose blood b12 levels are 'normal' but we still have severe b12d symptoms, ie functional b12 deficiency. If it helps, I would continue, despite what labs may or may not say.
It can take several years of regular injections for cognitive issues to reverse.
This also happened to me in the early hours of the morning in 2017 returning to Paradise CA from dropping my sister off at the Sacramento Airport. There was an intersection I crossed in which my spatial perception suddenly distorted and I almost drove into the ditch alongside the shoulder. Lucky it was in the very early hours with almost no traffic so that I did not endanger other drivers. Took me several minutes to recover my bearings and to recognize that my reflexes were off, for several minutes could not determine where I was.
Drove back slowly on a less direct less traveled route. Shortly after the MD treating me decided to go with treating the symptoms and gave me loading doses of B12 and injections thereafter.
That treatment literally saved my life November 8, 2018 because I would not have escaped the fire in the condition I was in before receiving B12 IM injections.
Many thanks for the link, very interesting reading. Interesting that it highlights that using serum B12 as a first line test for B12D (as in the UK) will miss a “significant” proportion of people with B12D. It seems to be suggesting (as I understand) that two biomarkers are needed - active B12 and MMA seem to be more successful in the places it mentions.
Lots of info on functional B12D in the article, which was also helpful.
I was struck by one section of the article that stated that adoption of a particular diagnostic algorithm (ie testing one biomarker instead of another) in a certain country had successfully achieved a 30 per cent reduction in diagnostic costs (which perhaps reflects an underpinning desire across the board to ‘optimise’ diagnostics (finding the ‘best value’ approach, which won’t necessarily identify everyone) - and with my set of blood results (functional B12 deficiency) I would have slipped through the net there…
Also, it states that only serum levels below 150 should be considered a B12 ‘deficiency’ - but (going from what posters on this forum say) - there are a lot of clinical signs / symptoms of deficiency in serum levels above 150. So this bit seems to be at odds with patient experience..
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