Signs of heart disease found in far-flung antique mummies
People tend to think of heart disease as a scourge of modern life, brought on by vices such as greasy fast food, smoking and the tendency to be a couch potato.
But 21st century CT scans of 137 antique mummies gathered from three continents show that hardened arteries have probably plagued mankind for thousands of years — even in places like the Aleutian Islands, where hunter-gatherers subsisted on a heart-healthy marine diet and occasional snacks of berries.
Fully a third of the mummies examined — who lived in the American Southwest and Alaska as well as Egypt and Peru as much as 5,000 years ago — appeared to have the same vascular blockages that cause heart attacks and strokes in Americans today.
The findings suggest that humans may have a basic predisposition to developing cardiovascular disease as they age, said Dr. Gregory Thomas, medical director of the MemorialCare Heart and Vascular Institute at Long Beach Memorial Medical Center and senior author of a study detailing the findings that was published online Sunday by the journal Lancet.
“We want to believe that we can prevent heart disease, that we don’t have to get it if we do the right things and go back to nature,” said Thomas, who is also a clinical professor of cardiology at UC Irvine. “I believed it too, until we scanned these people.”
But that doesn’t mean the millions of Americans who suffer from cardiovascular disease should abandon efforts to keep their hearts healthy, cautioned physicians who were not involved in the study.
“The message here is not that we can’t do anything about heart disease,” said Mayo Clinic cardiologist Dr. Stephen Kopecky, president of the American Society for Preventive Cardiology. “This is not a fait accompli.”
The new research, which was presented Sunday at a meeting of the American College of Cardiology in San Francisco, is an outgrowth of five years of work by a globe-trotting team that includes physicians, biologists and anthropologists.
In past years, the group has published and presented research showing that evidence of vascular disease was common in ancient Egyptian mummies. This time around, they wanted to examine the remains of people who might not have been as privileged as royals from the Nile delta — and therefore might have been less likely to eat a high-fat diet and loll about in luxury, habits well known to be hazardous to the heart.
So in addition to studying 76 scans of Egyptians who lived between 3100 BC and AD 364, the researchers reviewed radiologic images of mummified remains from five pueblo dwellers who lived in what is now Utah between 1500 BC and AD 1500; 51 Peruvians who lived between 900 BC and AD 1500, before Europeans arrived in South America; and five Aleutian hunter-gatherers who were alive in the pre-industrial period around AD 1900.
Gathering the images wasn’t easy, said USC gerontology researcher and study coauthor Caleb Finch.
One expedition was halted because of political unrest in Egypt.
In Peru, the team had to shuttle mummies from museum storage facilities to nearby hospitals. Guards were needed to safeguard the bodies, which are considered national treasures.
Once the mummies were safely transported, the scientists had to squeeze in their research scans during gaps in the clinical schedule when the CT machines weren’t in use by patients. “A sick child would go in, then our mummy would go in,” Thomas said. “It was surreal.”
Interpreting the scans wasn’t simple either. Some body parts were missing and dozens of mummies were balled up in the fetal position, which made interpreting the images more difficult.
In the end, seven experts analyzed each CT scan, debating what they were seeing in the images during weekly Saturday conference calls. They found the calcium deposits of atherosclerosis in mummies from all four cultures, with the New World specimens having buildups in the same places and in similar amounts as the Egyptians.
Like people today, the mummified subjects seemed to accumulate more plaques as they aged.
One Aleutian woman, approximately 50 years old, had such severe blockages of her right coronary artery that if she were alive now, her doctor would advise that she get stents, Thomas said.
In the final tally, the researchers determined that 47 of the mummies had “probable” or “definite” atherosclerosis, though they couldn’t tell whether the vascular disease was a cause of death.
Seeing the buildups in all four populations examined is a strong indicator that “there may be no environment or lifestyle which could eliminate atherosclerosis,” Finch said.
The mummified people would not have lived risk-free lives, the researchers noted in the Lancet report. Some would have been exposed to significant amounts of smoke from fires lit for warmth or cooking in their living quarters. Many — if not all — would have suffered frequent infections, which could cause inflammation that might have promoted atherosclerosis.
“There’s a lot that we don’t know about what causes heart disease,” said Dr. Robert Gillespie, a cardiologist at Sharp HealthCare in San Diego who was not involved in the study. “We know that eating a high-fat diet, smoking and hypertension all play a major role. But there’s a lot we’re missing. What’s the role of inflammation, infection and all these other things?”
Gillespie said these uncertainties should encourage patients to stick with their heart-healthy diets and exercise regimens.
“If you don’t control the things you can, you increase your risk even higher,” he said.
Thomas agreed, adding that the work shows that researchers “need to go back to the drawing board” and that “there must be something we haven’t understood yet.”
As part of the ongoing exploration, he and his colleagues are to return to Peru in April. Pending permission from authorities, they plan to conduct biopsies on one Andean mummy and to scan — and perhaps biopsy — yet more mummies from a fishing village.
They’ll attempt to rehydrate tissues from the bodies and examine them under a microscope to see whether plaques looked the same in the past as they do in patients today. Ideally, they’ll also evaluate the mummies’ DNA to see whether they had an elevated genetic risk for heart disease.