Heart disease: the greatest 'risk' factor of them all

By the turn of the last century, flying in the face of over a hundred years of research and clinical observation to the contrary, medicine abandoned the link between infection and atherogenesis; not because it was ever proven wrong, but because it did not fit in with the trends of a medical establishment convinced that chronic disease such as heart disease must be multifactorial, degenerative and non-infectious. Yet it was the very inability of 'established' risk factors such as hypercholesterolemia, hypertension and smoking to completely explain the incidence and trends in cardiovascular disease that resulted in historically repeated calls to search out an infectious cause, a search that began more than a century ago. Today, half of US heart attack victims have acceptable cholesterol levels and 25% or more have none of the "risk factors" associated with heart disease, including smoking, high blood pressure or obesity, most of which are not inconsistent with being caused by infection. Even the case of the traditionalist's latest 2003 JAMA assault to 'debunk' what they call the "50% risk factor myth" falls woefully short under scrutiny. In one group 30% died of heart disease with a cholesterol of at least 240 mg/dl, a condition which also existed in 21% who did not die during the same period. And the overlap was obvious throughout the so-called risk categories. Under such scrutiny, lead author Greenland conceded that if obesity, inactivity and elevated cholesteriol in the elderly are included, just about everyone has a risk factor and he likened the dilemma of people who do or do not wind up with heart disease akin to the susceptibility of people who are exposed to tuberculosis but do not get the disease. In Infections and Atherosclerosis: New Clues from an old Hypothesis? Nieto stressed the need to extend the possible role of infectious agents beyond the three infections which have in recent years been the focus of research: Cytomegalovirus (CMV) Chlamydia pneumoniae and Helicobactor pylori. Mycobacterial disease shares interesting connections to heart disease. Not only is tuberculosis the only microorganism to depend on cholesterol for its pathogenesis but CDC maps for cardiovascular disease bear a striking similarity to those of State and regional TB case rates. Ellis, Hektoen, Osler, McCallum, Swartz, Livingston and Alexander-Jackson all saw clinical and laboratory evidence of a causative relationship between the mycobacteria and heart disease. And Xu showed that proteins of mycobacterial origin actually led to experimental atherosclerosis in laboratory animals Furthermore present day markers suggested as indicators for heart disease susceptibility such as C-Reactive Protein (CRP), interleukin-6 and homocysteine are all similarly elevated in tuberculosis. It therefore behooves us to explore the link between heart disease and typical and atypical tuberculosis.