A Mummies Perspective on Atherosclerosis
By Alex Hepp
Recent techniques in modern science suggest that ancient humans were susceptible to the chronic diseases of today such as atherosclerosis. Atherosclerosis is a chronic inflammatory disease of the arteries that results in the buildup of cholesterol plaque in the wall of arteries, which reduces blood flow and oxygen supply to vital body organs and extremities.
The earliest documentation of atherosclerosis was discovered in Otzi the Iceman, a mummy dating back to 3300 BCE who displayed bilateral carotid calcific atherosclerosis under a computed tomography (CT) scan. CT scans can detect diseases and injuries by using a series of x-rays to produce a 3D image of soft tissues and bones. Today, atherosclerosis is generally accepted as having wide ramifications. It is considered the major cause of cardiovascular diseases which includes ischemic heart disease (IHD) and ischemic stroke. IHD and stroke are the world’s first and fifth causes of death respectively (Pahwa & Jialal, 2021).
The remains of humans, including mummies have been studied for centuries, however, it was only until recently and with new technology that scientists have been able to study atherosclerosis in mummified bodies. In 1852, an Austrian-German physiologist by the name of Czermak was the first to report atherosclerosis in ancient people. While autopsying the mummy of an elderly Egyptian woman, he found “multiple considerably large and calcified plaques” in her descending aorta. In 1908 Marc Ruffer, a Swiss-born pathologist and bacteriologist and a pioneer of modern paleopathy was able to autopsy mummies by rehydrating tissue. This led to further evidence of atherosclerosis in multiple Egyptian mummies and mummified limbs. Completing many autopsies, he was intrigued to find that these lesions indicative of atherosclerosis were as frequent 3,000 years ago as they are today (Clarke et al., 2014).
In more recent years, atherosclerosis has been identified in mummies by use of CT scans. In 2009 and 2010 the Horus study team imaged a total of 52 mummies at the Egyptian National Museum of Antiquities and of those, 20 had definite or probable atherosclerosis as defined by their level of calcification in the wall of the artery. The Horus team then transitioned to imaging mummies in Lima, Peru. These ancient Peruvians lived between 900 BCE and 1500 CE and of the 51 mummies scanned, 13 had definite or probable atherosclerosis.
Janet Monge from the University of Pennsylvania Department of Anthropology and Museum of Archaeology and Anthropology reviewed the whole-body CT images of five Ancestral Puebloan Native American mummies excavated from Southeast Utah and southwestern Colorado 120 years ago. One of the five mummies had definite atherosclerosis, and another had probable atherosclerosis.
Bruno Frohlich and his colleagues at the Smithsonian Institution reviewed whole body CT scans of five Unangan mummies who lived in the Aleutian Islands between 1756 and 1930 CE. Three of the five mummies had definite atherosclerosis.
Each of these four cultures differed in their physical locations, their lifestyles, and their diets, so it’s fair to wonder why atherosclerosis is so prevalent even among different communities. The epidemiologic and clinical work of thousands of researchers demonstrated that diet and lifestyle may have an impact on risk factors which contribute clinically apparent atherosclerosis. However, they also estimated that human genetics predicts approximately 50% of the prevalence for atherosclerosis (Pahwa & Jialal, 2021).
Additional insights from paleopathology suggest that our knowledge of the risk factors and etiology of atherosclerosis is incomplete, but it may be possible that atherosclerosis is a fundamental component of human aging. This idea is supported by data indicating that the prevalence of atherosclerosis is relatively stable among cultures, and studies that suggest arterial degeneration begins early in postnatal life and is progressive in all human populations (Wang et al., 2010).
However, the degree of atherosclerosis can be delayed by a lifelong avoidance of lifestyle risk factors. These include high blood pressure, smoking, obesity, high saturated fat diet, and physical inactivity to name a few. Additionally, those lucky enough to be genetically blessed may have lesser incidences of atherosclerosis. Those genetically predisposed to an abundance of low-density lipoprotein receptors and a loss of function single nucleotide polymorphism for PCSK9 which produces a lifetime of low LDL cholesterol allows for protection against coronary heart disease. (Clarke et al., 2014). These findings indicate that while genes may create the vulnerability of the disease, the environment determines if atherosclerosis will manifest itself in each individual.
Evolution also has a hand in driving heart disease such as IHD and ischemic stroke. The evolutionary mechanisms behind the emergence of atherosclerosis was likely for protection of previous threats to humans such as infection, injury, and starvation. However, it is ironic that now we have adapted to those threats and now are exposed to the deadly outcomes of inflammation and atherosclerosis present in our modern lifestyles.
Clarke, E. M., Thompson, R. C., Allam, A. H., Wann, L. S., Lombardi, G. P., Sutherland, M. L., Sutherland, J. D., Cox, S. L., Soliman, M. A., Abd el-Maksoud, G., Badr, I., Miyamoto, M. I., Frohlich, B., Nur el-din, A. H., Stewart, A. F., Narula, J., Zink, A. R., Finch, C. E., Michalik, D. E., & Thomas, G. S. (2014). Is atherosclerosis fundamental to human aging? Lessons from ancient mummies. Journal of Cardiology, 63(5), 329–334. https://doi.org/10.1016/j.jjcc.2013.12.012
Pahwa, R., & Jialal, I. (2021). Atherosclerosis. In StatPearls. StatPearls Publishing.
Wang, M., Monticone, R. E., & Lakatta, E. G. (2010). Arterial aging: a journey into subclinical arterial disease. Current Opinion in Nephrology and Hypertension, 19(2), 201–207. https://doi.org/10.1097/MNH.0b013e3283361c0b