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Autopsies found heart disease at 18
The autopsy studies
The first of these studies came in the 1970s, on people who died in Vietnam. It was repeated in the early 2000s on mostly young men, and some young women, who died in Iraq and Afghanistan. Studies like this tend to follow wars, and both found the disease taking hold without any ambiguity.
None of them were close to dying of atherosclerosis. It is a lifelong disease, and they were still 40 or 50 years from it.
The ApoB threshold
Atherosclerosis also cannot really develop until ApoB, the protein wrapping the LDL and VLDL particles that carry cholesterol, reaches a certain threshold, and most people pass it by their teens. An ApoB level of about 20 to 30 milligrams per deciliter makes it impossible to get atherosclerosis, so ApoB is necessary but not sufficient to develop the disease.
What did the Vietnam autopsies show?
In 1971, Joseph McNamara and colleagues published a study in JAMA of the hearts of 105 American soldiers killed in Vietnam, whose average age was 22. Nearly half showed some evidence of coronary atherosclerosis, and a few had severe narrowing of the arteries. It was among the first systematic looks at artery disease in healthy young adults.
How common was plaque in recent war dead?
Bryant Webber and colleagues reported in JAMA in 2012 on autopsies of 3,832 US service members killed between 2001 and 2011, whose average age was about 25. Roughly 8.5 percent showed coronary atherosclerosis. Prevalence rose with age across the group.
How does ApoB lead to plaque?
In 1995, Kevin Jon Williams and Ira Tabas proposed the response-to-retention hypothesis. ApoB-containing particles pass into the artery wall, where they stick to proteoglycans in the tissue. Retained particles get oxidized and attract immune cells, which turn into foam cells that form the core of a plaque. Each ApoB particle carries exactly one ApoB protein, so the ApoB level counts the particles that could get stuck.
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