2011-10-11

Vitamin Pills Not so Good For You

Tetrahydroimidizalone or Tomato:  
New Evidence that Foods are Better than Vitamins

The word vitamin is a marketing triumph.  It speaks of vitality, it speaks of Superman, and put those ideas and feeling together and you have a winner.  As a result, any chemical that can bear that name has had extraordinary success in the marketplace.  About 50% of all American adults take a multivitamin every day.

This makes vitamins the #1 set of chemicals that Americans take.  The question is, does taking a multivitamin really deliver?  Or like any other drug, are there down sides?

A new study published in the Annals of Internal Medicine, took a look at the fate of 38,772 women, average age 62, some who took multivitamins, and some who did not.  The study looked at how each group fared over a nearly 20 year period.  What they found was that the group that took multivitamins died a bit faster.  The study looked at a number of supplements.  The most dangerous was iron which substantially increased the rate or risk of death.  Just taking Vitamin A or D had little impact on the rate of dying, but taking a multivitamin did, it increased it.

This study adds further fuel to the argument that taking any drug, even one that sounds safe like vitamins, is not nearly as good for you as eating good food.

Consider just one vitamin.  This vitamin contains tetrahydroimidizalone, and is found in abundance in tomatoes.  Imagine someone trying to get you take a  tetrahydroimidizalone pill every day, it would be a very tough sell.  All your warning flags would be aroused.  What is  tetrahydroimidizalone?  Sounds very technical and dangerous.  What side effects does it cause?  And yet, about 50% of all adult Americans take this chemical every day, as long as it is called Vitamin B7, or biotin.

Now, there is no doubt that if you do not eat enough biotin, bad things happen to you.  But the question is, are you better off eating biotin-containing foods, or taking a pill of it?  The evidence for food is overwhelming at this point.  And the reason that makes sense is clear.  A tomato has lots of  tetrahydroimidizalone-rich biotin in it.  But it also has thousands and thousands of other compounds.  Further, humans and tomatoes evolved together.  As our ancestors found vines whose fruits helped us live, we cultivated those vine more.  As the benefit from a food grew over time, humans helped that food prosper.  The trend led to the evolution of highly complex foods that help us live.  Vitamins are a part of nearly all plants that we cultivate.

And yet, with only one exception, we have found that taking the vitamin out of the plant helps us in any way.  Vitamins work best when they work in concert with the tens of thousands of other chemicals in plants that we evolved to live on.  The one exception to date is folic acid, which as a pill, does prevent the development of spina bifida in pregnancy.

This study of so many women adds a dramatic extra level of evidence for this point.  In fact, now we can say that not only do multivitamins offer no benefit over eating a piece of fruit, but they may cause harm.

BOTTOM LINE
Despite the reassuring sound of the category, vitamins are like every other pill, they can cause harm.  A recent study demonstrates that the harm might include dying at a younger age.
We recommend that all your vitamin needs, with the exception of folic acid, be met by eating food.
We recommend that no one take a daily multi-vitamin, unless you have a specific medical condition requiring it.

Dr. Arthur Lavin




*Disclaimer* The comments contained in this electronic source of information do not constitute and are not designed to imply that they constitute any form of individual medical advice. The information provided is purely for informational purposes only and not relevant to any person's particular medical condition or situation. If you have any medical concerns about yourself or your family please contact your physician immediately. In order to provide our patients the best uninfluenced information that science has to offer,we do not accept samples of drugs, advertising tchotchkes, money, food, or any item from outside vendors.

2011-10-08

A Word on Screening

The Uproar over Screening for Prostate Cancer:
A Lesson in the World of Screening for us All

One of the most surprising aspects of modern medicine is how hard it is to create a screening test that  works well.

After all, what could be simpler than screening?  Screening just involves measuring something in everyone and finding those few whose measures are abnormal.  And then, knowing which of us has the problem, we can cure or eliminate it before it does any harm.

This is, in fact, the idea behind screening.  Find the problem early, reap the benefits of taking care of the problem before it causes any harm.

Some screening test methods do just that.  The best of them is the newborn screening test for a condition called PKU.  It was the first of all the newborn screening tests and it has all the features of a good screening program:
  1. The test is simple, inexpensive, and extremely safe.
  2. Essentially everyone with PKU tests positive, and everyone without PKU tests negative.  
  3. If you are found to have PKU in the newborn period, there is an action that can be taken that will ensure no harm will come to you.  If you have PKU and no one knows it, the intervention, which is simply to change your diet, cannot be offered and severe mental retardation will result.  The test result makes a dramatic difference.
  4. There is a system that allows all Americans to be tested at birth, for all positive results to be reported to the family and their doctor, and for those with PKU to receive the life-saving intervention.
The dirty little secret of screening, however, is that most techniques to do this do not work very well.  With few exceptions, most screening tests used in medical practice have a tremendous overlap, that is, people with positive results often do not have the problem.  Also, too often there is no clearly defined intervention or treatment that leaves the person reliably better off.

And yet, there is an explosion in the number of screening tests being developed.  As a result, every American is asked to be screened for a widening variety of problems, often without a good screening technology in place.  The test is available, but the test is often not a very good performer, not like the PKU test at all.

This has all come to our attention with the recent announcement that the screening test for prostate cancer, PSA, does not work very well.  This was the finding of the nation's leading authority on screening tests, the United States Preventive Services Task Force (USPSTF).  The USPSTF exists for only reason, to study screening tests and see if they work.

How could a screening test fail?  Well, it turns out that when you study them, they nearly all fail in some way or another.  The bottom line is that a screening test fails if, when all is said and done, it is likely not to help you.

How could a screening test turn out to cause more harm than good?  Here are some ways:
  1. The test could be so expensive, painful, and/or dangerous, that you are left more hurt than the problem you are looking for could have made you.
  2. The test could tell far too many people that they have the problem or disease when in fact they do not.  Imagine taking a test that told you had cancer when in fact you do not.  This turns out to be the most common problem with screening tests.
  3. The test could tell far too many people that they do not have the problem or disease when in fact they do.  This is a potentially devastating outcome, but fortunately, one problem current screening tests tend to avoid most of the time.
  4. When you look at everyone with a positive result and see how their problem eventually pans out, you might find they fare no better than those who skipped being screened who have the same problem.  That is, early detection may not make any difference.
  5. For some tests, there is no treatment available to help.  This makes the finding out early about the problem a rather futile exercise.
Figuring out how well a screening test actually performs turns out to be a tricky and complex task.   That is why the United States Preventive Services Task Force (USPSTF) deserves nothing but gratitude.  The USPSTF is a very thoughtful and careful group.  They review thousands of studies and look at screening tests for years before coming to a decision.   In the case of the PSA screening test for prostate cancer, they spent a very long time looking at the data, came to a conclusion in 2009, and then decided to spend two more years looking at the data again, to be sure they were advising us as accurately as possible.

What the USPSTF found was that the PSA test for prostate cancer is really a miserable failure as a screening test.  About half the men who are told they have prostate cancer as a result of this test turn out to not have any sort of cancer that would ever cause them harm.  Worse, of any group of men who have a positive PSA, no one can tell which of these men have actual, dangerous cancer, and which do not.  That dooms all men with a positive PSA to endure the burden of thinking they have cancer, and undergoing serious and potentially dangerous treatments.

The USPSTF found that when all is said and done, no lives have been saved by the PSA screening test, but tens of thousands of men have been rendered impotent, incontinent, or both, for no very good reason.

It is the response to this finding that exposes the power of the screening test in today's modern medical world.
In a  more rational world, one would expect the findings of an organization like the USPSTF to be accepted with tremendous interest and even gratitude.  Years of careful review and study should be.

But the medical world has reacted to this report with a howl.  Leading the charge are the urology associations.  Their response is clearly emotional and contains little data.  They state that they refuse to stand by and let their patients die by not having them screened with the PSA.  Of course, they have no information that demonstrates dropping the PSA test would actually lead to anyone dying.  Rather, they present stories of individuals whose lives appear to have been saved by the PSA test turning positive.  

Now, we all know which story is most convincing:

A harrowing story of a 58 year old man who thought he was well, only to find his PSA level was elevated, getting a prostate biopsy that shows he has prostate cancer, and then having his prostate removed and cured of a disease that could have killed him if he hadn't been screened.

A highly technical scientific report looking at the sensitivities, specificities, negative predictive values, and positive predictive values of the PSA test.  And in that same report, numbing tables and graphs looking at the statistical patterns of outcome for men screened with the PSA.

And yet, that really boring scientific report demonstrates that the 58 year old man in the first story has a very good chance of being misled.  The odds are so good that he did not really face any threat from prostate cancer, that he would have been just as likely to live out a healthy life without the PSA test!

Turns out facts do matter.

Sadly, as an outstanding group of epidemiologists at Dartmouth have found (and reported in their book Overdiagnosis, an outstanding book that I have blogged on earlier), money often trumps facts.  And the money element of screening is that it can turn a whole nation of healthy people into paying patients.


BOTTOM LINE
I present this story of the USPSTF, of PSA, of prostate cancer, to illustrate why we at Advanced Pediatrics take the science of screening so very seriously.

We look at every screening test recommended and look for data that groups like the USPSTF have on its performance.  If the test is a lousy performer, we do not recommend it.  We will never recommend a screening test simply because it screens for a serious illness, the test must actually deliver some benefit for us to tell you it's a good idea.

In the meantime, do trust the USPSTF.  They are careful, deliberate, and quite wise.


Dr. Arthur Lavin



*Disclaimer* The comments contained in this electronic source of information do not constitute and are not designed to imply that they constitute any form of individual medical advice. The information provided is purely for informational purposes only and not relevant to any person's particular medical condition or situation. If you have any medical concerns about yourself or your family please contact your physician immediately. In order to provide our patients the best uninfluenced information that science has to offer,we do not accept samples of drugs, advertising tchotchkes, money, food, or any item from outside vendors.

Intuniv- A Newer Medication for ADHD May Improve Working Memory

Intuniv- A Newer Medication for ADHD 
May Work By Improving Working Memory

Not too many years ago, a new medication was approved for use in treating attention deficit/hyperactivity disorder (ADHD).  That drug was brand-named Intuniv, an extended release form of the drug guanfacine.

Guanfacine was originally developed as a drug that could treat high blood pressure, but adults taking doses large enough to lower their blood pressure got quite sleepy.  The sedative properties of guanfacine led to it being used in lower doses to help quiet the raging behaviors of children with severely abnormal behaviors.  That version of guanfacine was called Tenex and it was fashioned to last about 4-6 hours per dose.  Now, children treated with Tenex often had problems with attention as well as extreme behaviors, and when they took Tenex an improvement in their ability to focus and pay attention was noted.

This led to the development of a form of guanfacine that was low enough in dosage to not sedate but enough of a dosage to improve attention and focus.  That is Intuniv, and one dose tends to last 12 hours.  It is a remarkably safe medication with few side effects aside from those relating to tiredness noted in many decades of use.

On October 6, 2011, the New England Journal of Medicine (365:14, p. 1346-7) published an article reviewing recent research describing what physically is causing the nearly universal loss of memory function as we get older.  That is, the normal loss of memory, not dementia.  What the article demonstrates is that the key type of thinking ability lost with age that explains the loss of memory is working memory.  This is yet another indicator of the central power of working memory to help the mind get tasks done.  Working memory is not really a type of memory, rather it refers to the ability of one's mind to hold more than one piece of information in the mind at one moment in time and do something with it.  

In this article, monkeys had the parts of their brain that creates working memory wired for measurement of activity, but also to allow various medications to be administered.  What they found was that when guanfacine was applied to the nerves that create working memory, older monkey's working memory was restored to that of young monkeys.  This, in turn, led to better ability to remember items, and to improved ability to get tasks done.

This is the first indication I have read of a medication demonstrating the ability to improve working memory.
As such, guanfacine, or Intuniv, works in a radically different way than stimulants such as Ritalin, Concerta, Adderal, Focalin, or Vyvanse.  The stimulants work by arousing the brain.  As we know a brain that is more alert works better.  That, after all, is what coffee is all about.  But Intuniv appears to work by actually changing the ability of the brain to create working memory function.

If this impact can be proven to be reliably present on use of Intuniv, and shown to be safe, it could make Intuniv a very interesting, powerful, and safe medication to consider when seeking to improve attention and focus.  It could yield changes that lie at the heart of attention deficits, without all the significant side effects of stimulants.

At the same time, it should be noted that there are interventions that have been proven to increase working memory without the use of any medication.  One of the most promising of such interventions is Cogmed, the product of serious neuroscience research and development in Sweden.  Cogmed, whose impact on working memory has been verified by independent laboratories, including the one, in England, that developed the concept of working memory, increases working memory significantly in 80% of those who complete the 5 week intervention.

Research into how the brain works is rapidly expanding our knowledge and our ability to help our minds work.  This recent report in the New England Journal of Medicine puts working memory once again at the center of how the mind gets tasks done.  It raises the possibility that a very safe medication, Intuniv, may be a specific intervention to boost working memory, and it increases the chance that interventions that require no drugs, e.g. Cogmed, are devoted to changing the right cognitive function.


Dr. Arthur Lavin



*Disclaimer* The comments contained in this electronic source of information do not constitute and are not designed to imply that they constitute any form of individual medical advice. The information provided is purely for informational purposes only and not relevant to any person's particular medical condition or situation. If you have any medical concerns about yourself or your family please contact your physician immediately. In order to provide our patients the best uninfluenced information that science has to offer,we do not accept samples of drugs, advertising tchotchkes, money, food, or any item from outside vendors.