You may have noticed that men and women are different. I hope you have noticed. As the French say, vive la différence! It’s not just that one has dangly bits and the other has bumpy chests. Or that one has to shave a beard and doesn’t like to ask for directions while the other has menstrual periods and likes to discuss feelings. There are differences in physiology and in the incidence of various diseases. For instance, normal lab values for hemoglobin are higher for men than for women, and autism is more prevalent in males while multiple sclerosis is more prevalent in females.
In the past, women have been underrepresented in clinical studies; when the first studies of aspirin for cardiovascular prevention came out, we knew it was effective for men, but we didn’t have enough evidence to recommend it for women. This is changing; researchers today are more aware of the need to include women in their studies. Now the American Heart Association/American Stroke Association (AHA/ASA) has issued the first evidence-based guidelines for reducing the risk of stroke in women. (more…)
In writing about science-based medicine, we give a lot of attention to medicine that is not based on good science. We use bad examples to show why science is important and how it is frequently misapplied, misinterpreted, misreported, or even wholly rejected. It’s a pleasure, for a change, to write about a straightforward example of the best of science-based medicine in action. The book Heart 411 is such an example.
The medical literature is a jungle of conflicting and complicated studies. It’s difficult for novices and even for sophisticated non-specialists to navigate. It’s useful to have experts as guides who can apply their knowledge, experience, and judgment to analyze the data and put everything into perspective. I can’t imagine anyone more qualified as guides to “matters of the heart” than the authors of this book. Heart surgeon Marc Gillinov and cardiologist Steven Nissen practice at the Cleveland Clinic, which has been ranked as the number one heart hospital by U.S. News & World Report for the last 15 years and is currently ranked 4th best hospital overall. They have treated more than 10,000 heart patients over 30 years of clinical practice and have also done extensive research and published hundreds of articles in peer reviewed journals. Their book contains everything they would like their patients to know about the prevention, diagnosis, and treatment of heart disease. It amounts to an owner’s manual for the heart. (more…)
A November letter to the editor in American Family Physician chastises that publication for misusing the term “secondary prevention,” even using it in the title of an article that was actually about tertiary prevention.
I am guilty of the same sin. I had been influenced by simplistic explanations that distinguished only two kinds of prevention: primary and secondary. I thought primary prevention was for those who didn’t yet have a disease, and secondary prevention was for those who already had the disease, to prevent recurrence or exacerbation. For example, vaccinations would be primary prevention and treatment of risk factors to prevent a second myocardial infarct would be secondary prevention.
No, there are three kinds of prevention: primary, secondary and tertiary. Primary prevention aims to prevent disease from developing in the first place. Secondary prevention aims to detect and treat disease that has not yet become symptomatic. Tertiary prevention is directed at those who already have symptomatic disease, in an attempt to prevent further deterioration, recurrent symptoms and subsequent events. (more…)
One of our readers asked that we evaluate a book I had not previously heard of: The China Study: Startling Implications for Diet, Weight Loss and Long-Term Health, by nutrition researcher T. Colin Campbell, PhD, with his non-scientist son Thomas M. Campbell II. The China Study was an epidemiologic survey of diet and health conducted in villages throughout China and is touted as “the most comprehensive study of nutrition ever conducted.” The book’s major thesis is that we could prevent or cure most disease (heart disease, cancer, diabetes, autoimmune diseases, bone, kidney, eye and other diseases) by eating a whole foods plant-based diet, drastically reducing our protein intake, and avoiding meat and dairy products entirely.
Opinions of the book
There’s a lot of praise for this book on the Internet. It was named VegNews Book of the Year. PETA loves it (not surprisingly). Heather Mills McCartney calls it inspirational. It was featured on Oprah.com and endorsed by two of her favorite doctors: Mehmet Oz and Dean Ornish. Its author was even interviewed on Coast to Coast AM.
But I also found this critical review which makes some excellent points and accuses the authors of misrepresenting the findings of the study. And this commenter on an Amazon.com forum also charges Campbell with misrepresenting the data from the study and points out numerous flaws in his reasoning.
I didn’t look at the praise or criticism of others until after I read the book, and the following represents my independent impressions. I approached the book as I do any book with scientific references: I read until I come across a statement of fact that strikes me as questionable and then I check the references given for the statement. This immediately got me off on the wrong foot with this book. In the first chapter I found the statement:
Heart disease can be prevented and even reversed by a healthy diet. (more…)
In the interests of fairness and intellectual honesty, I’ve forced myself to read a lot of really bad books. The True Believer tells me his guru’s book is the Real Stuff. He tells me I have a closed mind and won’t look at anything outside establishment dogma, and if I only read the book and understood Dr. Quack’s evidence and arguments, I would be a True Believer too. I have tried, really I have. I’ve given the Dr. Quacks every chance to convert me, and I’ve hoped to learn something new, but I’m always disappointed. I’ve come to the point that I feel like I’m reading the same book over and over: it is always a mixture of real science, pseudoscience, and speculation, based on cherry-picked evidence and argued with the same logical fallacies.
I recently got hooked into reading another one by a correspondent who had called me an “ignorant relic” for writing a “grossly ignorant article” about alternative medicine. I suggested he read R. Barker Bausell’s book Snake Oil Science and a couple of others, which he promised to do. Then he said, “If I am willing to buy three books that you have suggested and read them and you are not willing to read what I have suggested, then that pretty much says all that needs to be said.”
I was willing, even though the very title of the book suggested that its message was incompatible with the scientific evidence as I know it: How to Prevent and Treat Cancer with Natural Medicine. The authors are big names in naturopathic and herbal medicine: Michael Murray, Tim Birdsall, Joseph Pizzorno, and Paul Riley. It’s nowhere near as bad as some of the bad books I’ve read, but it is a good example of the genre and I’ll use it to illustrate why I call them bad.
It offers “an arsenal of disease-fighting tools for prevention, treatment, and coping with side effects” (Yes, it offers tools; but do those tools work?) And it promises to “change your internal environment so cancer can’t survive.” (Wow! If it could really do that, every oncologist in the world would enthusiastically adopt these methods and the authors would be eligible for a Nobel prize.)
Much nonsense has been written in the guise of longevity medicine. In Fantastic Voyage, Ray Kurzweil explains why he takes 250 pills every day and spends one day a week at a clinic getting IV vitamins, chelation, and acupuncture. He is convinced this regimen will keep him alive long enough for science to figure out how to keep him alive forever. In Healthy Aging, Andrew Weil chips in with his own mixture of science and magic. I pointed out the flaws in their reasoning in a review for Skeptic magazine – available online. There are many other popular books that promise to tell you how to live longer. Most of them amount to little more than speculation based on extrapolations from animal studies, in vitro studies, and odd non-clinical facts.
There simply is no evidence that any intervention will extend the human life span. The most promising idea from animal studies, severe calorie restriction, is not practical or palatable and would make adequate nutrition difficult. We don’t know how to prolong human life to, say, 130 years; but we do know how to prevent a number of diseases from causing premature demise at 60 or 70. That’s what real “longevity medicine” means.
To counteract all the belief-based and speculation-based “longevity medicine,” we needed a science-based longevity book. And now we have it. Carl Bartecchi, MD and Robert W. Schrier, MD have written a book entitled Living Healthier and Longer – What Works, What Doesn’t. The price is right – it is available online for free download. (more…)
Over 26 million Americans are taking statin drugs. Some people think they should be available over-the-counter without a prescription, and it has even been facetiously suggested that they should be added to our drinking water. The protective effect of statins in cardiovascular disease and in high-risk patients with high cholesterol levels is well established. But what about people with no heart disease and normal cholesterol levels – can they benefit too?
The New England Journal of Medicine has pre-released an important new study on statins online prior to its planned publication date of November 20, 2008. It is certain to stir up a lot of controversy, and the International Network of Cholesterol Skeptics will not be happy, because it contradicts some of their favorite arguments. They have claimed that statins do more harm than good, that reducing cholesterol levels is harmful to health, that the benefits of statins and/or cholesterol lowering do not extend to women and the elderly, and that studies showing benefits of statins are meaningless because they do not show reduction of overall mortality. This study indicates otherwise. (more…)
I recently read an article in Discover magazine entitled “Stop the Madness.” It was about a new treatment program that allegedly can prevent schizophrenia and other forms of psychosis. I found it very disturbing.
The PIER (Portland Identification and Early Referral) program was founded by a psychiatrist, Dr. William McFarlane, in Portland, Maine. It has recently expanded to 4 other US sites and there are similar programs in several other countries. PIER is an effort to find and treat patients in the “early stages of deterioration towards psychosis,” so as to prevent the development of psychotic illnesses like schizophrenia, bipolar disorder, and major depression. The program involves various psychosocial interventions and psychotropic drugs.
On the surface it sounds promising, but there is a dark side. I’m particularly concerned about the use of antipsychotic drugs in people who haven’t been diagnosed as psychotic. (more…)