‘Bypass Brain’: How Surgery
May Affect Mental Acuity

McDougall in the News – Wall Street Journal

Dr. John & Mary McDougall

Dr. John & Mary McDougall

In the United States alone nearly half a million people undergo coronary artery bypass surgery (CABG) annually, and many, if not most, will be permanently altered, mentally and emotionally, by surgically induced brain damage. According to the authors of the 2008 Annals of Neurology Wall Street Journal article, “A review of contemporary studies concludes that 30 to 65% of patients have evidence of cognitive decline 1 month after surgery…. In one study of cognitive outcomes after article cited in today’s CABG, it was reported that 42% of the patients had worse cognitive performance at 5 years than at baseline. The occurrence of late cognitive decline 5 or more years after surgery has been reported by other investigators, although some studies have not found evidence of delayed decline several years after CABG.”

The fatal insult to the patient’s non-replaceable nervous system tissue is caused by microembolization—the release into the circulation of thousands of tiny particles of debris. These artery-blocking particles are created by the heart-lung machine and by clamping the aorta. You can learn more about this damage and see pictures of microemboli lodged in the arteries of patients’ eyes (retinas) by reading this 2005 article in the American Heart Association’s journal Circulation (Circulation . 2005;112:3833-3838.)

The reason for all the controversy about brain damage is heart surgery is big business—$100 billion annually, with 80% of the income of a typical hospital coming from the treatment of heart disease. I believe money is the primary reason that patients and their families are never informed about this expected complication.  Furthermore, I believe the primary motivation for designing and publishing studies that create doubt in the minds of doctors and patients is to preserve and protect the bypass surgery business.  Note that the authors of the 2008 Annals of Neurology study are from the Departments of Neurology and Surgery; Division of Cardiac Surgery, Johns Hopkins University School of Medicine.

This 2008 Annals of Neurology study observed the mental changes of two groups of patients from their institution over a period of 6 years and found that although both groups showed significant mental decline, there was no difference between those who had had bypass surgery and those who did not.  As a result they concluded bypass surgery is not the cause of this decline, but instead these mental changes are a result of normal aging and underlying vascular disease (atherosclerosis).

How did they get those results? The number of patients studied was small (244) and they were exceptionally sick. Consider that 17% of the patients from the surgery group and 21% of the non-surgery group died within 6 years, even with the best that medicine and surgery have to offer.  The main flaw of the study was that about 35% of both groups were lost to follow-up. Patients lost to follow up in this, and other studies, are the ones most likely to have significant brain damage—the ones most needed to reach a valid conclusion. (See the accompanying editorial by Yaffe ; Ann Neurol 2008; 63:547-8).

In 2005 this same group from the John Hopkins University Cardiac Surgery department published a similar article “disproving” brain damage from bypass surgery (Neurology 2005;65:991-9).  Although these findings did not appear in the abstract—the synopsis portion of the article most doctors read—they did state the following finding twice in their publication: “At 3 months, both surgery groups (CABG and off-pump) reported more changes for the worse in personality, memory, and reading books (see table E-1). At 12 months, the differences between the two surgery groups and the nonsurgical cardiac controls in subjective symptom reporting persisted, particularly the frequency of self-reported change in memory for the CABG group.” So, they really did find evidence of brain damage from CABG—maybe the researchers from the Cardiac Surgery Department of John Hopkins have forgotten?

Certainly, heart surgery, even with all of the disadvantages of the heart-lung bypass machine, is a modern medical miracle when used to save and improve lives, like in the patients with congenital heart defects and valve disease. But the lifesaving, life-improving benefits of heart surgery do not apply to the vast majority of the half million patients who undergo bypass surgery annually.  Neither angioplasty nor bypass surgery saves lives (with a few debatable exceptions). You can read this same conclusion in a recent Business Week article, “Is Heart Surgery Worth It?”. The heartbreak caused by this out-of-control business is compounded further by the fact that the underlying disease is prevented and the artery blockages are reversed with a sensible diet and a healthy lifestyle. But the debate will continue because the threat of brain damage from heart surgery would be a business-killer.

Read more about this subject in my newsletter articles:

September 2004: What Next, Bill Clinton

April 2008: Readers’ Comments on Bill Clinton’s Madness

By: Dr. John McDougall, M.D.

McDougall Wellness Center P.O. Box 14039, Santa Rosa, CA 95402
©2008 John McDougall All Rights Reserved

Used with permission of Dr. John McDougall June 12, 2008