Jack W. Dini
Livermore, California
(This appeared in HealthFactsandFears.com of the American Council on Science and Health, August 13, 2007, http://www.acsh.org/factsfears/newsID.1022/news_detail.asp)
Be cautious when you hear that some disease has all of a sudden increased in numbers. Someone may have changed the rules. Examples include Alzheimer’s, blood pressure, diabetes, autism, and obesity.
The National Center for Health Statistics (NCHS) substantially changed the data for many causes of death in 1999. One was Alzheimer’s which jumped by at least 55 percent above the level reported in 1998. This increase did not reflect a sudden surge in mortality but a change in classification which has a substantial bearing on the epidemiology of the disease. (1)
According to Marcia Angell, high blood pressure was defined for many years as above 140/90. An expert panel then introduced something called prehypertension in 2003, which is something between 120/80 and 140/90. Overnight people with blood pressure in this range found they had a medical condition. (2)
While on the subject of heart disease, Robert Ehrlich notes that a so-called epidemic of heart disease was said to have occurred after World War II in the US. Since this was also a period when meat became increasingly available it might appear to have supported the heart-diet theory. But as Ehrlich notes, “there was no epidemic at all. The risk of dying from heart disease was unchanged for any given age group. The real change was that people were living longer to the age when they were more likely to die from diseases of old age such as coronary heart disease.” What also happened was that physicians in the post-war era began to catch on to the new terminology and were more likely than before to write coronary heart disease on death certificates. In one single year, 1948 to 1949, the addition of the term ‘arteriosclerotic heart disease’ to the International Classification of Disease had the effect of raising the CHD death rate by 20 percent in white males and 35 percent in white females. (3)
Fast forward to the present and a July 21, 2007 report in the British Medical Journal (BMJ). Julia Hippisley-Cox and her colleagues concluded that misdiagnosis of heart disease has led to massive over-prescribing of drugs. (4) Flaws in the way doctors routinely calculate risk led to misinforming patients they were in danger of developing life-threatening heart diseases. The researchers tracked 1.28 million healthy men and women aged between 35 and 74 over a period of 12 years to April 2007. As Polly Curtis reports, “The traditional way of calculating risk from heart disease involves a score based on smoking, blood pressure, and ‘good’ and ‘bad’ cholesterol, along with age and sex. The BMJ study compared this measure against a new, more sophisticated test, which also takes into account social deprivation, genetic factors and weight. It found that the former over-predicted the number of people at high risk of developing cardiovascular diseases by 35%. It concludes that 3.2 million adults under the age of 75 are at risk of developing cardiovascular illnesses compared with the 4.7 million previously estimated.” (5) This indicates that anti-cholesterol drug statins are massively and needlessly over-prescribed in the UK.
Another ailment that’s up in the last last twenty years is diabetes. Aggressive educational programs designed to encourage more testing, and mass screenings of millions of Americans have contributed to the increase. However, most importantly, the definition of diabetes has been changed from a fasting blood sugar of 140 to a blood sugar of 126. So, just like with some of the previous health issues, millions of Americans became diabetic overnight. (6)
Why is Autism on the rise? Scott Lilienfeld and Hal Arkowitz suggest changes in diagnostic and legal practices have played a key role. For decades it was 1 in 2,500, then from 1993 to 2003, a 756% increase occurred. Now it is 1 in 166. In 1980 the American Psychiatric Association manual listed six of six criteria that defined autism. In 1994 the manual required any eight of sixteen criteria. In addition, the 1980 version contained only 2 diagnoses relevant to autism while the 1994 version contains 5 such diagnoses. Legal changes cited by Lilienfeld and Arkowitz relate to an amended version of the Individuals With Disabilities Act, passed by Congress in 1991. This required school districts to provide precise counts of children with disabilities and resulted in sharp surges in the reported numbers of children with autism. Yet, these numbers are not based on careful diagnoses of autism or on representative samples of populations. They note, “As a consequence, researchers rely on ‘administrative based estimates’ which come from government data submitted by schools, and will arrive at misleading conclusions about autism’s prevalence.” (7)
If folks reading this are a representative sample of the US population, 2 out of every 3 of you are either overweight or obese. I, for one, am included in the overweight category. In my case it happened overnight in 1998. Perhaps the same thing happened to you. It wasn’t because I had gone on a binge of eating and drinking. Rather it was because a committee convened by the National Heart Institute redefined overweight to be a body mass index (BMI) of 25 or more for both men and women. (Body mass index equals your weight in kilos divided by the square of your height in meters. If you prefer to use English units, its your weight in pounds divided by the square of your height in inches, then multiplied by 703). I had a BMI of 25.8, so now I was overweight. Before 1998, a man was officially overweight with a body mass index of 27.8 and a woman at 27.3, but now the rules had changed and all of a sudden many more people were ‘overweight.’
BMI is solely a function of height and weight. It does not distinguish between men and women, between 20 year olds and 80 years olds, or between people of radically different bone structures or musculature types. Former National Football League Jerry Rice (now a famous dancer) is 6’2” and weighs 200 pounds. His 25.7 BMI puts him in the ‘overweight’ category. (At a BMI if 25.8 you can see I’m in good company). Paul Campos calculates that ‘97% of the players in the NFL are either overweight or obese. I doubt you would think of Hollywood stars such as Richard Gere, Pierce Brosnan and Kevin Costner as being overweight, yet with their respective BMI’s of 26.1, 27.1, and 29.2, Gere and Brosnan are overweight and Costner is borderline obese. George W. Bush, known for his good health, is ‘overweight’ since his BMI is 26.3. (8) One could go on and on with these kinds of examples, but I think by now you get the point.
Here are some interesting calculations. University of Virginia professor Glenn Gaesser points out that “studies have consistently failed to find any correlation between increasing BMI and higher mortality in people sixty-five and over 78% of the approximately 2.3 million annual deaths in the United States occur among people who are at least sixty-five. Thus 78% of all deaths lack even the beginning of a statistical link with BMI.” (9)
W. Wayt Gibbs reports, “Three surveys—medical measurements collected in the early 1970s, late 1970s, and early 1990s, with subjects matched against death registries nine to nineteen years later—indicate that it is much more likely that US adults who fall in the overweight category have a lower risk of premature death than do those of so-called healthy weight. The overweight segment of the ‘epidemic of overweight and obesity’ is more likely reducing death rates than boosting them.” (10)
Here’s one final bit of information on overweight. For years the Centers of Disease Control (CDC) have reported that 400,000 Americans die each year because of obesity. Guess what happened recently? The CDC changed the 400,000 number to 28,000. David Brooks sums it up quite well, “The chief moral lesson I take away from the recent CDC report is that Mother Nature is happy to tolerate marginally irresponsible behavior. She doesn’t want you to go completely to seed. If you’re truly obese and arouse hippos when you visit the zoo, you could still punch your ticket at any moment. But she does want you to eat the occasional Cinnabon, so long as it isn’t bigger than Delaware.” (11)
Summary
Many folks concerned about their health have only a ‘headline or TV news’ awareness of the issue of concern. More often than not, these headline news stories overemphasize minute risks about which little can be done and ignore those that readers can do something about. Repeated often enough, these scares eventually become myths and most people never hear the full story. Sometimes the rules for diagnosing diseases are changed but this gets lost in all the fear-mongering.
So my suggestion for you is, the next time you hear some new science or health scare fact, try to find the rest of the story. What was the sample size? Did some committee change the guidelines for an illness or disease? There are not mad cows on your block. Ebola is not lurking in your drain and you are not going to die from SARS, West Nile Virus, or bird flu. Your family is not threatened by chemical assaults. They’re threatened by people with a blood alcohol level of 0.25 driving 2 tons of steel.
References
1. Rodger Doyle, Scientific American, 284, 26, May 2001
2. Marcia Angell, The Truth About Drug Companies, (New York, Random
House, 2004), 85
3. Robert Ehrlich, 8 Preposterous Propositions, (Princeton, NJ,
Princeton University Press, 2003), 273
4. Julia Hippisley-Cox et al., “Derivations and validation of QRISK, a
new cardiovascular disease risk scare for the United Kingdom: prospective
open cohort study,” British Medical Journal, 335(7611), 136, July 21, 2007
5. Polly Curtis, “1.5M wrongly told they risk heart disease,”
Guardian Unlimited, July 6, 2007
6. Paul Campos, The Obesity Myth, (New York, Gotham Books, 2004), 22
7. Scott O. Lilienfeld and Hal Arkowitz, “Autism: An Epidemic?”
Scientific American Mind, 18, 82, April/May 2007
8. Paul Campos, The Obesity Myth, 132
9. Paul Campos, The Obesity Myth, 17
10. W. Wayt Gibbs, “Obesity: An Overblown Epidemic?” Scientific American,
292, 70, June 2005
11. David Brooks, “Survival of the not quite fittest,” The Times-Picayune,
New Orleans, April 26, 2005, page B-7
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