Lessons about disease...from mummies
(CNN) — Talk about a startling juxtaposition: A mummy in a CT scanner. You may be wondering: Why in the world would a mummy get a CT scan?
It turns out that preserved peoples are great study subjects, especially when you are trying to figure out the roots of health problems that span millennia.
A study released Sunday in The Lancet suggests that atherosclerosis - the disease that makes arteries go rigid, and is a leading cause of death worldwide - may have been around for thousands of years.
"We like to say that we found the serial killer that's stalked mankind for 4,000 years," said Dr. Randall Thompson, attending cardiologist at Saint Luke's Mid America Heart Institute, and lead author of the study.
The proof lies under the fine linen folds of mummies from ancient Egypt and Peru, the southwestern United States, and the Aleutian Islands in Alaska. Scientists scanned 137 of them and found that more than one-third had definite or probable atherosclerosis.
Twenty-five of the 47 mummies had "definite disease," according to the study, while the other 22 had probable disease. And evidence of atherosclerosis was found in mummies representing all four geographic areas.
"It is intriguing," said Dr. Richard Becker, professor of medicine at Duke University School of Medicine, who was not involved in the study. "One could look at this and say this is not solely a disease of westernized civilizations. Atherosclerosis perhaps has been around for a long time."
Glowing white flecks of what appeared to be calcium showed up in the same places on CT scans - the aorta and the coronary and carotid arteries, for example - where it is found in people today. (Turns out that calcium does not decay; it stays lodged in the body for thousands of years.)
"These populations...had very different diets, very different lifestyles," said Thompson. "And there was a very wide span of history and wide geographic distribution. The disease was present and not hard to find."
That geographic and lifestyle diversity is key to this study.
Previously, Thompson and his colleagues found evidence of atherosclerosis in Egyptian mummies. The findings suggested that our modern, unhealthy lifestyle may not deserve full blame for atherosclerosis - after all, even ancient Egyptians had the disease.
"But after we reported our findings in ancient Egyptians we were criticized," said Thompson. "They were eating a diet that was rather rich and did not get much physical activity. They lived a lifestyle like ours, so it was not so surprising after all."
This most recent study found atherosclerosis in populations that subsisted on things like corn, squash, nuts, berries and fish - and were active - so our unhealthy, modern habits may play a lesser role in developing this disease than we think.
When the current crop of mummies was subjected to further analysis, calcium build up seemed to happen as a function of age, not diet and physical activity. But that does not mean that we modern people should ignore those other risk factors for atherosclerosis.
"If you have less control than you think you do, that's more reason to control what you can, like cholesterol, exercise and do things we know are healthy," said Thompson.
The problem, according to Thompson, is when patients feel weighed down by guilt because they can't control their diabetes or exercise enough.
"Some of that guilt is misplaced," said Thompson. "I think that some of the excessive focus on diet is oversold."