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Old 12-28-2004, 10:48 PM
Roland Deschain Roland Deschain is offline
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Could donating blood on a regular basis help control primary hypertension?

Two factors caused me to consider this possibilty:
1. I read a journal article about five years ago ( I'm not sure if it was Science, Nature, JAMA or some other journal) that discussed the possible role of Fe in coronary heart disease. The article even suggested that one of the reasons that women may have a lower risk profile before menopause is the regular blood and concurrent iron loss that go with the process.

2. The fact that one of the ways that hypertension is treated is with diuretics. Giving blood is one way to at least temporarily lower circulating blood volume.


Actually, here's an even better question that just occured to me. Have there been any significant studies on the health ramifications of regular blood donations positive or negative?
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Old 12-28-2004, 11:07 PM
WhyNot WhyNot is offline
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It's certainly not recommended (and hopefully a more knowledgeable Doper will be along soon to explain why) but my Dad did exactly this for years and years. He donated twice as often as allowed, by going to two different blood banks, and watched his blood pressure rise slowly between donations. After each donation, the blood pressure lowered to acceptable levels.

He stopped doing this when he was chewed out by several doctors in a row. I don't know what their reasons were, just that it was A Bad Thing.

However, I do know that women don't lose anywhere near a unit of blood when we menstruate. It's actually only 30-40 mL, and only part of that is blood. And acording to this site, "Most authorities would accept that regular menses in excess of a measured menstrual blood loss of 80 mL of bleed each month will inevitably lead to anaemia." So blood donation more than once a month could also lead to anemia.
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Old 12-29-2004, 12:20 AM
KarlGauss KarlGauss is offline
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Yes, there is some evidence that iron may play a causal role in coronary disease and atherosclerosis (presumably by promoting oxidation) but it is by no means conclusive.

Here is a study which is not great, but it is consistent with your hypothesis that regular blood donation may influence the development of coronary disease.
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Old 12-29-2004, 03:34 PM
Roland Deschain Roland Deschain is offline
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Thanks, for the study link. I would certainly like to know why Why Not's father was advised not to donate blood. Perhaps, the process of regularly donating blood "ramps up" the body's own natural erythropoietic process. This could be non desirable in someone who naturally already has primary hypertension. Furthermore, if they pause, cease or otherwise interrupt their normal donation routine we might see the sort of "rebound" hypertension associated with those who quit taking their anti-hypertensive medications. Of course this is just conjecture and I lean towards the hypothesis that regular blood donations has a posivite effect upon the risk of CHD, CVA's, and embolism.

I am surprised that there doesn't seem to be more research into the long term health ramifications (again be they positive or negative) of regular blood donations. Millions of people give blood, and are encouraged to do so on a regular basis. Since the operative maxim in medicine should be to "first do no harm", we should have a solid foundation of research supporting the safety of such a procedure before encouraging people to donate blood. My paranoid side wonders if the "big business" aspects of blood donation do not intrude upon detached, objective analysis of potential benefits and risks.
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Old 12-29-2004, 03:50 PM
Malodorous Malodorous is offline
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Quote:
Originally Posted by Roland Deschain
Thanks, for the study link. I would certainly like to know why Why Not's father was advised not to donate blood. Perhaps, the process of regularly donating blood "ramps up" the body's own natural erythropoietic process.
Hmm...I wonder if long-distance runners could give blood regularaly to get the same sort of effect as training at altitude.
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Old 12-29-2004, 04:02 PM
barbitu8 barbitu8 is offline
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Originally Posted by Malodorous
Hmm...I wonder if long-distance runners could give blood regularaly to get the same sort of effect as training at altitude.
What many of them used to do was "blood doping." They'd remove some erythrocite cells and inject them before an important event. After removal, the body regenerates the cells and then when they are injected, the blood will have more of them - which some argue is a good thing because the blood can carry more oxygen. However, it also makes the blood thicker. In any event, this procedure has since been declared illegal.
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Old 12-29-2004, 09:52 PM
WhyNot WhyNot is offline
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Quote:
Originally Posted by Roland Deschain
Thanks, for the study link. I would certainly like to know why Why Not's father was advised not to donate blood.
I called Dad, and he said (based on his memory of about 15 years ago) that it was the frequency of his donation that got him yelled at, not the donation itself. The docs said that if his pressure was high, it was high, and needed treatment which included drugs, losing weight and eating better, not periodic draining off at a rate twice that recommended. They were, indeed, worried about anemia. They were also worried because, in their eyes, he wasn't getting "treatment" at all, just masking his symptoms by untested methods. Perhaps this would be looked at differently today.

Frankly, if 'twas me, I'd ask for a hemoglobin and iron level, and keep donating until they showed up low. IANAD, for obvious reasons.
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Old 12-29-2004, 10:53 PM
Alvis Alvis is offline
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I once thought about this in terms of a constant maintenance via letting out just enough blood to get the pressure down to the desired level every day. This points out the obvious problem: with pressure maintained by less blood flowing through the same constricted pathways, the heart and lungs will just be greater taxed to maintain the same levels of cellular oxygenation.
  #9  
Old 12-29-2004, 10:58 PM
Little Nemo Little Nemo is offline
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The last time I went to donate blood, I was refused because my blood pressure was too high. Personally, I thought this was a silly reason to refuse to accept a donation from me: wouldn't draining off a pint lower my blood pressure? But realistically, there must be a legitimate reason for this.
  #10  
Old 12-30-2004, 05:52 AM
Broomstick Broomstick is online now
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There is a genetic disorder called hemochromatosis whcih causes the body to absorb and store abnormally high amounts of iron. Over time, the excess iron cuases all sorts of damage to various organs, including the heart, and can lead to a relatively early death, not to mention a miserable existance prior to that death.

There is no cure, but the treatment is... regular blood letting. Initially, this is done more frequently than blood donation until normal iron levels are reached, after which they put the person on a maintenance schedule. I believe a year or two ago US authorities decided it was safe to use this blood in donations (it was barred until they figured out why this was happening in some people). So far as I know, that's the only case where more frequent than normal blood donation is condoned.

As far as treating hypertension with blood letting... IANAD, but I think part of problem with blood pressure is not too much blood, but the muscles in the blood vessels that maintain and control pressure exerting too much pressure. Maybe by lessening blood volume, those muscles have to clamp down even harder to maintain adequate pressure and so it can just exacerbate the problem. Just a guess.

In any case - using blood donation to lower blood pressure is treating a symptom without trying to get to underlying causes, which usually is not the best way of deadling with a problem. A low salt diet, exercercise, and so forth, although not as quick, seems more of a reset of the body's mechanism for controlling blood pressure.
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Old 01-01-2005, 12:51 AM
Roland Deschain Roland Deschain is offline
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Here is another study from the University of Kansas in 1997 that supports the role of regular blood donation in reducing the risk of MI http://www.sciencedaily.com/releases...0901072035.htm . It mentions that the studies author seeks to do a more extensive follow up study, but I have not been able to find information about this if it occured (maybe he couldn't get the funding or the research is ongoing.
  #12  
Old 01-01-2005, 01:03 AM
Roland Deschain Roland Deschain is offline
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Quote:
Originally Posted by Roland Deschain
Here is another study from the University of Kansas in 1997 that supports the role of regular blood donation in reducing the risk of MI http://www.sciencedaily.com/releases...0901072035.htm . It mentions that the studies author seeks to do a more extensive follow up study, but I have not been able to find information about this if it occured (maybe he couldn't get the funding or the research is ongoing.
By the way to all of the Chicago journalists who read these boards if there is anything to this it is a significant news story since it deals with America's number one killer (heart disease) and if true would significantly increase the incentive to donate blood (which in and of itself directly benefits people as well). Also, no one as of yet addressed my question/observation that there seems to be a paucity of studies and data concerning the short and long term health ramifications of regular blood donations. This is an especially important question given that we are discussing a procedure which has significant physiological impact, and is normally done on healthy individuals.
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Old 01-01-2005, 09:09 AM
irishgirl irishgirl is offline
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The hypertension of middle age and obesity is related to atherosclerosis, SIADH and the problem of getting an essentially normal blood volume through abnormally narrow vessels.

Diuretics remove excess fluid from the blood, thus depleting its volume without losing valuable cells necessasry to oxygenate tissue and provide immunity. Other hypertension drugs lower blood pressure by relaxing the vessels so that there is a wider space for the blood to flow through. Anticoagulants prevent the blood from clotting as it moves through the small vessels, ensuring they are not further blocked.

Basically, if your arteries are seriously clogged up with cholesterol deposits, you will have an MI whether your blood volume is low or not, because eventually the lumen of the vessels will become so narrow that no blood at all can pass through.

The anti hypertensive drugs aren't just trying to get your blood pressure down, they are trying to correct the mechanism which caused it in the first place. That is why most people start lipid lowering therapy when they are diagnosed with hypertension, and are advised to give up smoking (which promotes atherosclerosis and increases pressure by contracting the smooth muscles in vessel walls).

Rather than giving blood once a month, give up smoking, cut down on fatty foods, alcohol and salt and exercise daily. You'd notice that your blood pressure goes down, even without taking any anti-hypertensive drugs.
  #14  
Old 01-01-2005, 12:10 PM
Roland Deschain Roland Deschain is offline
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I am of course familiar with the DASH diet and other approaches to managing hypertension, but this is intended as a scholastic, academic question into an important area of (I believe neglected) medical knowledge. Keep in mind that while atherosclerosis undoubtably contributes to many cases (and perhaps a majority) of hypertension that it is by no means the only cause. Primary or essential hypertension is by it's very nature of undefined etiology (or it would be secondary hypertension). Furthermore, the fact that there seems to be a paucity of research on the long term health effects of what is to some degree an invasive medical procedure (that millions regularly engage in) should alarm most thinking people (at least in my opinion).
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Old 01-01-2005, 01:50 PM
KarlGauss KarlGauss is offline
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There have been at least two allusions to atherosclerosis as possibly contributing to hypertension. In fact, except for renal artery stenosis (an uncommon process), atherosclerosis does not play a causal role in the genesis of hypertension. Moreover, this thread is about primary hypertension which, by definition, is not secondary to another process such as atherosclerosis.

I will also point out that SIADH has nothing to do with hypertension.
  #16  
Old 01-01-2005, 01:57 PM
picunurse picunurse is offline
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irishgirl is absolutely right!
Without giving a physiology lesson on pre-load and after-load, and the renin/angiotension/aldostrone cascade, suffice it to say that blood is not just a liquid to hold blood vessels open.
Iron may indeed play a part in cardiovascular health, but eating less red meat would be a more intelligent way of decreasing that risk.

Roland Deschain, the article you linked to is from 1997 and is retrospective. Meyers never published the definitive study he proposed at that time. I checked KU's sites, he is still doing CV research, so, my guess is, the blood donation study didn't produce the results he expected and it was abandoned. KU has always been pretty liberal with research money, so I doubt if that was the issue.

Roland Deschain, primary hypertension is linked to the aforementioned renin/angiotension/aldosterone cascade. It is poorly understood, but it is not a volume issue. The research surounding trace elements and CV health show some promise. Iron storage and metabolism may still be a factor in CV disease, but blood letting isn't the answer.
If you like, I'll be happy to link to something on R/A/A cascade. Its complicated and pretty boring if you aren't in the biz, but If you're interested...
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Old 01-01-2005, 02:10 PM
picunurse picunurse is offline
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Here's a link to the Renin Angiotension Aldosterone Journal, it may be to esoteric. I do have others.
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Old 01-01-2005, 06:41 PM
Roland Deschain Roland Deschain is offline
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I don't believe that the issue of whether or not blood donation is positive or negative with regard to CHD risk can be answered one way or the other with current research. However, the more important point concerns why it is that we have so little research on the long term health effects of blood donation when so many people (including myself) engage in this activity. My point is that there should be long term studies on this issue (and not just with regard to CHD, but also immune suppression/enhancement/cancer risks or benefits associated with the activity). How can we even know that it is safe if no one is monitoring the health (from a population perspective) of those who donate blood?
  #19  
Old 01-01-2005, 08:35 PM
picunurse picunurse is offline
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Quote:
Originally Posted by Roland Deschain
I don't believe that the issue of whether or not blood donation is positive or negative with regard to CHD risk can be answered one way or the other with current research. However, the more important point concerns why it is that we have so little research on the long term health effects of blood donation when so many people (including myself) engage in this activity. My point is that there should be long term studies on this issue (and not just with regard to CHD, but also immune suppression/enhancement/cancer risks or benefits associated with the activity). How can we even know that it is safe if no one is monitoring the health (from a population perspective) of those who donate blood?
darn hamsters!
I had a long post explaining the magnitude of a controlled donor study, but the hamsters...
Anyway, the problem is any feasible study of blood donors would have to be retrospective, like the one you linked to earlier. Retrospective studies are flawed because the researcher has no way to control the variables.
A controlled study would be too cumbersome and costly.
As far as negatives from donation, that's covered by the "duck" theory... If it looks like a....
Too many people have donated without obvious ill effects, not perfect, but pretty much undeniable.
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Old 01-01-2005, 10:27 PM
Roland Deschain Roland Deschain is offline
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Quote:
Originally Posted by picunurse
darn hamsters!
I had a long post explaining the magnitude of a controlled donor study, but the hamsters...
Anyway, the problem is any feasible study of blood donors would have to be retrospective, like the one you linked to earlier. Retrospective studies are flawed because the researcher has no way to control the variables.
A controlled study would be too cumbersome and costly.
As far as negatives from donation, that's covered by the "duck" theory... If it looks like a....
Too many people have donated without obvious ill effects, not perfect, but pretty much undeniable.
The problem with the relying on casual observation is that is can miss the forest for the trees. Consider, that it is only recently that we have been able show that vitamin E supplementatoin above 200IU's per day probably has negative consequences for cardiovascular health (perhaps indirectly by decreasing the effectiveness of statin drugs, but then again the incidence of all mortality was increased beyond this level). It was only meta analysis of multiple studies which made this conclusion possible. Compariable situations can be found with the COX-2 inhibitors (especially Celebrex which was considered safe by most doctors for many years). Another example of medical interventions thought safe, but now scrutinized are the administration of certain antidepressants in children. However, at least these issues were being studied consistently if not intensely. The same cannot be said with regard to the long term health effects of blood donation.

What is more the above items are intended to treat disease (or in the case of Vitamin E forestall it). However, blood donation is done usually by healthy individuals to help others (or for money in the case of lower income individuals). Indeed, selling blood, and blood products from donars is a multimillion (billion?) dollar business. If it turned out that the procedure raised the risk of contracting certain conditions it would raise serious questions of exploitation. Perhaps, I feel stronger than most about this issue since my wife, myself, and mother in law all gave blood three times this month in part to "keep the lights on" until our student loans/grants come through in Jan (this was in addition to working of course).

Without regard to the above I tend to believe that giving blood has either neutral or positive health ramifications. What bugs me is that I can cite no research to support this position.
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Old 01-02-2005, 06:00 AM
picunurse picunurse is offline
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Quote:
Originally Posted by Roland Deschain
The problem with the relying on casual observation is that is can miss the forest for the trees. Consider, that it is only recently that we have been able show that vitamin E supplementatoin above 200IU's per day probably has negative consequences for cardiovascular health (perhaps indirectly by decreasing the effectiveness of statin drugs, but then again the incidence of all mortality was increased beyond this level). It was only meta analysis of multiple studies which made this conclusion possible. Compariable situations can be found with the COX-2 inhibitors (especially Celebrex which was considered safe by most doctors for many years). Another example of medical interventions thought safe, but now scrutinized are the administration of certain antidepressants in children. However, at least these issues were being studied consistently if not intensely. The same cannot be said with regard to the long term health effects of blood donation.

What is more the above items are intended to treat disease (or in the case of Vitamin E forestall it). However, blood donation is done usually by healthy individuals to help others (or for money in the case of lower income individuals). Indeed, selling blood, and blood products from donars is a multimillion (billion?) dollar business. If it turned out that the procedure raised the risk of contracting certain conditions it would raise serious questions of exploitation. Perhaps, I feel stronger than most about this issue since my wife, myself, and mother in law all gave blood three times this month in part to "keep the lights on" until our student loans/grants come through in Jan (this was in addition to working of course).

Without regard to the above I tend to believe that giving blood has either neutral or positive health ramifications. What bugs me is that I can cite no research to support this position.
First, blood donation, at least in the US is always voluntary, never paid for. The exception being plasma, which is actually another process. The amount a reciepient or his insurance pays for a transfusion only covers the cost of processing and handling. US blood banks are non profit. I can't speak to the practices in other countries.
Your examples are exactly why blood donation is safe, since the use of Vit E as a CV protectant, and the release of Cox-2 inhibitors are recent. The number of effected individuals is minute compared to the millions who have donated blood since the first Blood Bank opened in the US in 1936.
With your 2 examples, the anecdotal evidence became overwhelming in a couple years. If anything, even a subtle problems were generated from blood donations, it would be glaringly obvious after nearly 60 years.
Also, there is data collected with blood donations. Most, of course, is focused on the blood, itself, but demographic information is gathered and can be cross referenced to the blood fairly easy.
Much of what we know about blood borne illnesses has been gathered in the process of banking blood.
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Old 01-02-2005, 07:26 AM
Roland Deschain Roland Deschain is offline
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I don't wish to debate in GQ, but everyone in my family got paid $20.00 per "shot"for blood not Plasma donation. The location was Aventis at somewhere around the 5500 block of East Washington Street in Indianapolis Indiana (they paid more for plasma, but we didn't wish to do that since it takes longer).

Also, here is an article http://www.bloodbook.com/part-1.html from the Philadelphia Inquireer that discusses how blood donation is anything, but a non profit business in reality. There was another from the New York Times, but I cannot find the link right now.

You say that problems (or benefits) from donation would be obvious, but is there even a centralized clearing center fo adverse reactions to blood donation (such as as exists for vaccines at the CDC). Also, if I develop cancer or heart disease ten years from now who would even consider that blood donations might play a role (not that I think they do)?
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Old 01-02-2005, 08:54 AM
picunurse picunurse is offline
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Quote:
Originally Posted by Roland Deschain
I don't wish to debate in GQ, but everyone in my family got paid $20.00 per "shot"for blood not Plasma donation. The location was Aventis at somewhere around the 5500 block of East Washington Street in Indianapolis Indiana (they paid more for plasma, but we didn't wish to do that since it takes longer).

Also, here is an article http://www.bloodbook.com/part-1.html from the Philadelphia Inquireer that discusses how blood donation is anything, but a non profit business in reality. There was another from the New York Times, but I cannot find the link right now.

You say that problems (or benefits) from donation would be obvious, but is there even a centralized clearing center fo adverse reactions to blood donation (such as as exists for vaccines at the CDC). Also, if I develop cancer or heart disease ten years from now who would even consider that blood donations might play a role (not that I think they do)?
I have to once again, apologize. I've only worked in states where blood is volunteer donor only. I find these states are actually in the minority.
Also, The once non-profit status has indeed changed into big business.
Now, On the upside.. I found a list of studies about, or using blood bank data.
  #24  
Old 01-02-2005, 09:11 AM
muttrox muttrox is offline
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Gee, as a regular Red Cross donor, reading this thread's links has been a bit depressing.

Remember, many of the guidelines for blood donation have nothing to do with your own health, but have to do with the likelihood of donating "bad" blood.
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Old 01-02-2005, 05:37 PM
barbitu8 barbitu8 is offline
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Quote:
Originally Posted by Roland Deschain
Consider, that it is only recently that we have been able show that vitamin E supplementatoin above 200IU's per day probably has negative consequences for cardiovascular health (perhaps indirectly by decreasing the effectiveness of statin drugs, but then again the incidence of all mortality was increased beyond this level).
How can a megastudy "show" that above 200 IUs per day of vitamin E supplementation "probably" has negative consequences for cardiovascular health. Either it shows it or it just indicates the probabability. Anyway, I thought that applied only to those with preexisting heart conditions. Do you have a cite?
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Old 01-02-2005, 06:13 PM
KarlGauss KarlGauss is offline
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Quote:
Originally Posted by barbitu8
How can a megastudy "show" that above 200 IUs per day of vitamin E supplementation "probably" has negative consequences for cardiovascular health. Either it shows it or it just indicates the probabability. Anyway, I thought that applied only to those with preexisting heart conditions. Do you have a cite?
Perhaps he was referring to this:
Quote:

Miller, Edgar R. III MD, PhD; Pastor-Barriuso, Roberto PhD; Dalal, Darshan MD, MPH; Riemersma, Rudolph A. PhD, FRCPE; Appel, Lawrence J. MD, MPH; Guallar, Eliseo MD, DrPH

From The Johns Hopkins School of Medicine, The Johns Hopkins Bloomberg School of Public Health, and The Welch Center for Prevention, Epidemiology and Clinical Research, The Johns Hopkins Medical Institutions, Baltimore, Maryland; National Center for Epidemiology, Instituto de Salud Carlos III, Madrid, Spain; University of Edinburgh, Edinburgh, Scotland, United Kingdom; and University of Tromso, Tromso, Norway.


Meta-Analysis: High-Dosage Vitamin E Supplementation May Increase All-Cause Mortality.


Annals of Internal Medicine. 142(1):37-46, January 4, 2005.

Abstract

Background: Experimental models and observational studies suggest that vitamin E supplementation may prevent cardiovascular disease and cancer. However, several trials of high-dosage vitamin E supplementation showed non-statistically significant increases in total mortality.

Purpose: To perform a meta-analysis of the dose-response relationship between vitamin E supplementation and total mortality by using data from randomized, controlled trials.

Patients: 135 967 participants in 19 clinical trials. Of these trials, 9 tested vitamin E alone and 10 tested vitamin E combined with other vitamins or minerals. The dosages of vitamin E ranged from 16.5 to 2000 IU/d (median, 400 IU/d).

Data Sources: PubMed search from 1966 through August 2004, complemented by a search of the Cochrane Clinical Trials Database and review of citations of published reviews and meta-analyses. No language restrictions were applied.

Data Extraction: 3 investigators independently abstracted study reports. The investigators of the original publications were contacted if required information was not available.

Data Synthesis: 9 of 11 trials testing high-dosage vitamin E (>=400 IU/d) showed increased risk (risk difference > 0) for all-cause mortality in comparisons of vitamin E versus control. The pooled all-cause mortality risk difference in high-dosage vitamin E trials was 39 per 10 000 persons (95% CI, 3 to 74 per 10 000 persons; P = 0.035). For low-dosage vitamin E trials, the risk difference was -16 per 10 000 persons (CI, -41 to 10 per 10 000 persons; P > 0.2). A dose-response analysis showed a statistically significant relationship between vitamin E dosage and all-cause mortality, with increased risk of dosages greater than 150 IU/d.

Limitations: High-dosage (>=400 IU/d) trials were often small and were performed in patients with chronic diseases. The generalizability of the findings to healthy adults is uncertain. Precise estimation of the threshold at which risk increases is difficult.

Conclusion: High-dosage (>=400 IU/d) vitamin E supplements may increase all-cause mortality and should be avoided.

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