Posted on 02/04/2012 12:51:48 PM PST by neverdem
ORLANDO – People with an excessive blood level of vitamin D from overdosing with supplements had a 2.5-fold increased incidence of atrial fibrillation(A Fib), based on a study of 132,000 residents of Utah and southeastern Idaho.
The finding "suggests the need for caution with vitamin D supplementation and the need for careful assessment of serum levels if high doses [of vitamin D] are used," Megan B. Smith said at the annual scientific sessions of the American Heart Association.
The finding also suggests that patients identified with new-onset atrial fibrillation should be evaluated for a possible extremely high vitamin D level, said Ms. Smith, although in the results she reported, the high blood level of vitamin D linked with a significantly elevated incidence of atrial fibrillation, greater than 100 ng/dL, was extremely unusual, occurring in just 291 of the 132,000 people (0.2%) included in the study.
Although the mechanism linking such an extremely elevated blood level of vitamin D to a markedly increased rate of new-onset atrial fibrillation remains unclear, a likely explanation is the hypercalcemia that vitamin D toxicity can cause. Hypercalcemia can, in turn, reduce cardiac conduction velocity and shorten cardiac refractory time, said Ms. Smith, a dietician at Utah State University in Logan.
"Utah [residents have] tremendous use of supplements. From what we’ve seen in the charts we have, excessive use of vitamin D supplements is the primary driver" of the high levels seen, said Dr. T. Jared Bunch, director of electrophysiology research at the Intermountain Medical Group in Murray, Utah, and lead investigator for the study. "The few patients [with very high vitamin D levels] who I have seen got vitamin D in their milk, from a multivitamin, and from vitamin D pills. They get it from multiple sources," but added that the low prevalence of levels above 100 ng/dL also showed that it is a difficult level for a person to reach.
"Utah has an enormous problem with vitamin D deficiency, so we had this large group of people" who were members of Intermountain Healthcare, and had their vitamin D level measured once as part of their routine care. A survey by Dr. Bunch and his associates showed that unless asked, people don’t usually tell their physician that they take a vitamin D supplement, and that physicians at Intermountain Health do not usually ask patients about their vitamin D intake.
The measurement numbers documented the extent of the vitamin D deficiency problem, with 38,000 of the 132,000 people measured (29%) having a blood level below 20 ng/dL. This group with vitamin D deficiency showed significantly elevated prevalence rates of diabetes, hypertension, coronary artery disease, heart failure, and depression, compared with people in the designated "normal" vitamin D range of 41-60 ng/dL. But notably the incidence of atrial fibrillation in the deficiency group was not significantly different than the rate in the reference group with a normal vitamin D level at baseline.
"There is something unique" about the excess, toxic level, for atrial fibrillation incidence, Dr. Bunch said in an interview.
To better examine the potential role of vitamin D in elevating atrial fibrillation risk, Dr. Bunch and his associates are now regularly measuring blood vitamin D levels in Intermountain Healthcare members and prospectively tracking their atrial fibrillation incidence.
The results reported by Ms. Smith came from a retrospective analysis of the one-time vitamin D measurement by an immunoassay, and atrial fibrillation incidence tallied over an average 584 days of follow-up based on ECG testing and ICD-9 codes in each person’s medical record. The most common vitamin D level measured was 21-40 ng/dL, in 73,547 people (56%). Another 17,234 people (13%) had a level of 41-60 ng/dL, which the researchers considered normal and which they used as the reference group.
During follow-up, the incidence of new-onset atrial fibrillation was about 1.5% in all subgroups based on their baseline vitamin D level, except for those with a level above 100 ng/dL, who had an incidence of about 4%. A multivariate analysis that controlled for baseline differences in demographics identified a significantly elevated atrial fibrillation rate only in people with a baseline vitamin D level greater than 100 ng/dL.
Ms. Smith and Dr. Bunch said that they had no disclosures.
See comment# 1.
Some folks are born with the characteristic "square heart". Others can develop it through intense exercise ~ e.g. the sort of training needed for cross-country skiing or regular marathon runs.
If you have an extra sinus (spare current carrying nerve to the heart), it can begin firing when you don't want it to, and that will interfere with the motor sequence leading to fibrillation.
Reading through the Scandinavian (Swedish) research in the Skolt (a Sa'ami tribe of about 500 people living in Finland), this particular heart structure is clearly associated with success at cross country reindeer "herding", living outdoors all the time, winter and summer, and frequent heavy labor during periods of intense cold.
It could also enable you to breath easier than other, more Tropical humans, in very cold air simply because greater use of the atrial chambers allows you to pump more blood through the lungs ~ and that allows you to breath in less cold air ~ to maintain the same oxygenpressure ~ and removal of CO2.
Not a big thing of course but in that climate getting by with fewer breaths probably has a survival advantage.
There are a cluster of genetically driven conditions associated with this including not having enzymes to metabolise alcohol (a tough one, eh), anomalous heme production (leading to an anemia called pernicious anemia), and so forth. That is, if you have one such condition, the odds are good that you have at least one, or all, of the others.
Now does that mean you have a Sa'ami ancestor? In general, probably, but they've been mixing into the general population in Europe for over 1,000 years! Watch those guys swimming in Antarctic waters ~ they probably have square hearts ~ and could develop troublesome arrhythmias in the future ~ or maybe not. My grandfather had the problem, my father had it, I don't! I have associates who know of this problem back over many generations, with many deaths, and yet others don't have any deaths at all.
This report/study probably needs to have the Sa'ami background filtered out. Otherwise readers may draw some quite erroneous conclusions.
I eat raw fish ~ and if it’s still wiggling around it’s really great for pulling in the vitamins and minerals you need.
Right, my daughter's congenital heart condition was caused by Mg deficiency as was a friend's lung cancer
Absurd, impossible-to-disprove statement from the great quack tradition.
Many of us do take Mg supplements. Magnesium is just one factor, like Vitamin D.
Mine came on after, ironically, I began BP meds.
Doctors probably hate the internet but my cursory research says that one particular drug produces arrhythmia in 31% of patients.
My SO is a chronic/recurrent A-FIB sufferer, and has been taking 5000IU of D3 for the past year - could this be of concern to her??
If it was me, then I would get the serum 25-hydroxyvitamin D test to make sure it was below the upper limit of normal. This links a quick tutorial about A Fib by a cardiologist. I'd want to rule out reversible causes of it. After that, it's time to see a cardiologist.
Thanks for the response, neverdem -
I guess I wasn’t very clear in my description of the situation - the onset of her A-Fib was more than two years ago, and she just started taking the D3 supplements approximately a year ago - so I guess my question was whether the 5000IU daily dosage would be considered high enough to exacerbate an existing condition...
Occasionally I have noticed this same thing but continued exercise usually clears it up. I’ve had a-fib since 1994 but it is controlled with Betapace. A very nasty situation for anyone who has it and it is like having a chest full of monkeys.
My opinion would be that the a fib people are taking calcium with the d3 supplementation. Most Americans probably have too much calcium in their diets before any supplementation of calcium. It may be possible to upload too calcium with the assistance of d3.
My opinion would be that the a fib people are taking calcium with the d3 supplementation. Most Americans probably have too much calcium in their diets before any supplementation of calcium. It may be possible to upload too calcium with the assistance of d3.
Actually, it wasn’t hard for me to get my level up to 143, which is way, way too high.
My daughter left a bowl of what I thought were gummy bears in her room. I just started munching on them, taking a handful every day when I went into her bedroom. Turned out they were Vitamin D supplements candies she had bought at Walmart.
The whole article only mentions Vit. D. Yes, one can get too much by taking plain Vit. D. But vit.D3 is a different thing. I’m not sure what is different about it, but I have read that it’s nearly impossible to get too much with the D3. I take 2500 a day and do not get colds.
You misread the title. You missed where it said Elevate A Fib Risk . . .
IOW, you won't tell more lies (or fibs), just that the ones you do tell tend to be whoppers. [grin]
Dr. Cannell’s vitamin D regimen
"On the weeks I cannot sunbathe, I take 5,000 IU/day of vitamin D."
He hawks it on radioinfomercials with vitamin K2, magnesium and boron, IIRC. I take 4000 IU of vitamin D3. I get another 400 IU of D2 in a multivitamin. Everyone is different. IIRC, I posted a story about vitamin D from this same source that told about black taking vitamin D were more likely to get calcified arteries.
Skepticism Mounts on Need for Vitamin D Supplementation
Discussing findings from a recent cross-sectional study involving 340 African American patients with type 2 diabetes, Dr. Buckley said that serum 25-hydroxyvitamin D levels were positively associated with increased calcified atherosclerotic plaque in the aorta and carotid arteries (J. Clin. Endocrinol. Metab. 2010 Jan. 8, 2010; [doi:10.1210/jc.2009-1797]All I'm saying is that if you're going to play your own doctor, you better know what you're doing. Vitamins are not necessarily benign. You can overdose on vitamin A too. There was a study to prevent prostate cancer with vitamin E. Those who got vitamin E had 17 % more diagnoses of prostate cancer according to a doc on Charlie Rose last night.“The effects of supplementing vitamin D to raise the serum 25-hydroxyvitamin D level on atherosclerosis in African Americans are unknown. Prospective trials are needed,” the investigators said.
lol. oh, it makes you tell bigger lies. heh.
” lol. oh, it makes you tell bigger lies. heh. “
So, following that line of reasoning, then it’s safe to postulate that politicians eat Vit D capsules by the bowlful, with a spoon... (Milk and sugar optional...)
Dem Congressional Leaders and denizens of the White hut jse a skip-loader....
;)
My a-fib was caused by a low (still within normal) potassium level coupled with the stress of major surgery. There are various reasons for it to occur. Sometimes the body asserts its independance and does what it wants.
Yep.
Politicians have a secret brand of cereal, Vita D cereal meets 100% of your daily Fib needs.
I finally gave it a try last year, after contracting chest congestion that just kept hanging on. Started at 3,000 IU and will occasionally up it to as much as 6,000 if I’m feeling subpar. The congestion broke up, and the effect was comparable to Mucinex. Haven’t had as much as a head cold since, and I’ve always been one to catch whatever bug is going around.
It’s cheap, the apparent benefit is good and the downside appears to be limited to extremely high dosages, at a level I’ve never approached. I plan to continue taking 3,000 - 6,000 IU daily.
Last fall, my doctor discovered my vitamin D3 25-hydroxy level was just 10. I started taking it daily at a low dose and now 5000 IU’s a couple times a week. My last report after about 5 + months showed a level of 48.
I can honestly say that since raising the level my triglycerides are right at normal, my cholesterol is around 200 and blood glucose has normalized at around 6 on a periodic A1C lab test.
Like a miracle. Feel better than I have in years! I’m a believer in Vitamin D3 25-hydroxy.
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