Tuesday, July 12, 2016

Can We Really Believe Degenerative Diseases Are "Disappearing"? That Depends

In her breezy Sunday Review piece ('A Medical Mystery: Diseases In Decline')  in The New York Times (July 10, p. 7) author Gina Kolata makes a number of incredible claims about progress in conquering degenerative diseases. She writes:

"Major diseases like colon cancer, dementia and heart disease are waning in wealthy countries and improved diagnoses and treatment cannot fully explain it...scientists marvel at the good news, a medical mystery of the best sort and one that is often overlooked as advocacy groups emphasize the toll of diseases and the need for more funds."

While admitting the three diseases noted are "far from gone" and "still cause enormous suffering and kill millions each year", Ms. Kolata goes on to babble "But it looks as if people in the U.S. and wealthy countries are, unexpectedly, starting to beat back the diseases of aging".

Errr...I don't think so. I think it more likely Ms. Kolata is a victim of selection effects and statistics rendered too optimistic by cherry picking data.  Let's take colon cancer where she writes:

"Colon cancer is the latest conundrum. While the overall cancer death rate has been declining since the early 1990s, the plunge in colon cancer deaths is especially perplexing. The rate of colon cancer deaths has fallen nearly 50 percent since its peak in the 1980s, noted Dr. Douglas J. Robertson of the Geisel School of Medicine at Dartmouth and the Veterans Affairs Medical Center in White River Junction, Vt.

Screening they said is only part of the story...None of the studies showing the effects of increased screening for colon cancer has indicated a 50 percent reduction in mortality".

Let us first note that "increased screening" in the case of colon cancer screening, does not mean an absolute increase in the population being screened. It really means a small relative population (to the aggregate)  that undergoes screening at regular intervals. This includes those for whom polyps have been found and who need to return at 3, 5 -year intervals.  These contrast with an alternative, significant population that never has and never will allow colon cancer screening. This may be for a variety of reasons, including lack of knowledge or ethnicity- related sensibilities, i.e. many immigrants do not avail themselves of such screening - males in particular. They regard it as invasive and "unmanly" to undergo such screening. Many other Americans, native born, also avoid such screening for the same reason. It has been estimated, e.g. by Dr. Deborah Fisher, gastroenterologist from Duke University, that possibly up to 40 million adult Americans have never been screened. I know them from my own family.

If this is so, and they are harboring potentially cancerous polyps - as I was until I found out during one screening in 2007 then again in 2010-  then it is clear Kolata's encouraging stats are ...how should we call it? Comprising a statistical 'fool's paradise'.  Dr. FIsher estimates it takes something like 20 years for an adenomatous  polyp to become cancerous which means if all those go on without screening we could see an explosion of colon cancer in the next 10-20 or even 30 years - among the over 50s. And what she doesn't mention is that there has been a disturbing increase in cases for the under 50 year olds who are screened.

The point here is that a gastroenterologist cannot screen a person who refuses to be tested, and there are millions  of potential colon cancer patients not  getting tested  - for any number of reasons (including the sheer inconvenience, grief of the prep).   This is why Dr. Fisher, for example, has been a strong proponent of the fecal occult blood test (not the same as cologuard)since the principle should be "some test is better than none".

We have to infer then that Kolata's colon cancer conclusion is based more on aberrations in the data arising from missing tests, as opposed to higher frequency across the affected populations.  If this hypothesis is true, we will see an abrupt increase in  colon cancer rates in the next 10-20 years. We will see!

In terms of dementia Kolata declares:

"Dementia rates too have been plunging. It took a few reports and more than a decade before many people believed it. but data from the United States and Europe are becoming hard to wave off. The latest report finds a 20 percent decline in dementia incidence per decade, starting in 1977. With more older people in the population every year, there may be more case in total, but an individual's chance of getting dementia has gotten lower and lower."

This is definitely off, and a result of Kolata indiscriminately bundling all types of dementia, including vascular and the actual disease (Alzheimer's) that shows no sign of abating at all.   She even acknowledges in the next paragraph how vascular dementia has been reduced largely because of the control of blood pressure which has reduced "mini strokes from vascular disease that cause dementia".

This is true but it still leaves out the genesis of dementia from Alzheimer's  which doesn't depend entirely on cardiac factors. We also know from medical stats compiled about the disease that its incidence is dramatically increasing (cf. Alzheimer's Association medical briefs):

"The number of Americans living with Alzheimer's disease is growing — and growing fast. An estimated 5.4 million Americans of all ages have Alzheimer's disease in 2016.
  • Of the 5.4 million Americans with Alzheimer's, an estimated 5.2 million people are age 65 and older, and approximately 200,000 individuals are under age 65 (younger-onset Alzheimer's).
  • One in nine people age 65 and older has Alzheimer's disease.
  • By mid-century, someone in the United States will develop the disease every 33 seconds.
These numbers will escalate rapidly in coming years, as the baby boom generation has begun to reach age 65 and beyond, the age range of greatest risk of Alzheimer's. By 2050, the number of people age 65 and older with Alzheimer's disease may nearly triple, from 5.2 million to a projected 13.8 million, barring the development of medical breakthroughs to prevent or cure the disease. Previous estimates based on high range projections of population growth provided by the U.S. Census suggest that this number may be as high as 16 million. "

Epidemiological stats back up these claims from the Alzheimer's Association, the single largest body at the forefront of Alzheimer's  funding. It simply isn't a matter of inventing dreary stats to get more funding.

Kolata is correct when she notes that: reduction in vascular disease does reduce cardiovascular risk factors "that are also risk factors for Alzheimer's" - but the former are not singularly determinant identifiers for the disease, which still lean to alterations in the brain itself (e.g. formation of beta amyloid plaques). Until the latter are finally tagged and the genesis recognized there will be no real decrease in the Alzheimer's stats, no matter how vascular dementia cases have decreased.

It is great that cases of dementia overall have been decreasing, but to generate optimism based on mixing up the two main types of dementia doesn't really serve a useful purpose other than to propagandize with baseless PR.

We need to get at the bottom of exactly why  someone in great cardiovascular health (like Janice's cousin Desmond shown)  who would swim a mile each day - even into his early 70s-  could suddenly develop Alzheimer's and revert to the level of an infant.. If cardio risk factors don't explain such decline, and they don't for most Alzheimer's patients, then we are fooling ourselves believing Kolata has on offer anything other than medical puff and pabulum.

Kolata is on much firmer ground with heart disease (deaths having fallen 60 percent from their peak) , but if one has followed the development of statins, and their widespread prescription, now to the $50 billion a year level- the explanation for its decrease is evident. Along with more people stopping smoking and getting more exercise, e.g. at gyms.  But an ancillary outcome of rising statin use is increased liver disease and need for transplants - a result of nasty side effects for too many .  See e.g.

In my first (and only) attempt at using even a mild, low dose statin five months ago, I became violently ill, vomiting and with  dizziness - along with yellowing skin (jaundice) that developed over the next few days. Had I not stopped cold turkey I might be awaiting (and needing) a liver transplant too!

Kolata concludes by suggesting the "conquest" of these diseases may be leading to a kind of  subduing of  aging itself. since "all these degenerative diseases share something in common ...something inside aging cells themselves".

Maybe, but I wouldn't hold my breath waiting for 140 -year life spans, minus "degenerative diseases".

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