Persistent, low-grade infections contribute to cardiovascular disease by sustaining a background of systemic inflammation and by directly disrupting vascular biology. Microorganisms from the mouth, lungs, or chronic wounds can provoke immune activation that never fully resolves, driving processes that favor atherosclerosis, thrombosis, and plaque rupture. Evidence linking inflammation to cardiovascular events includes work by Paul M. Ridker, Brigham and Women's Hospital showing that targeting inflammatory pathways reduces major cardiac events, which supports inflammation as a causal mediator rather than a benign correlate.
Mechanisms linking infection to vascular disease
Chronic infections elevate circulating cytokines such as interleukin-6 and tumor necrosis factor-alpha and increase hepatic production of C-reactive protein, a marker and amplifier of vascular inflammation. These mediators promote endothelial dysfunction by reducing nitric oxide bioavailability and increasing adhesion molecule expression, which encourages monocyte recruitment into the arterial wall. Within the intima, macrophages ingest lipids and become foam cells; ongoing immune stimulation favors formation of a necrotic core and a thin fibrous cap, characteristics of unstable plaques more likely to trigger myocardial infarction or stroke. Some pathogens or their products may also be detected in atherosclerotic tissue, suggesting local microbial influences on plaque biology, while antigenic mimicry can sustain auto-inflammatory responses that perpetuate injury.
Clinical and societal implications
Oral infections such as periodontitis have been repeatedly associated with higher cardiovascular risk in epidemiologic studies and mechanistic research by Richard J. Genco, State University of New York at Buffalo linking periodontal pathogens to systemic inflammatory markers. At the same time, randomized antibiotic trials against single organisms have not consistently reduced cardiovascular events, highlighting that the key driver is often the host inflammatory response rather than a simple treat-and-clear model. This nuance affects clinical strategy: preventing and managing chronic infections, improving access to dental care in underserved communities, and addressing social determinants of health can reduce the burden of persistent inflammation. Environment and territory matter because crowded living conditions, limited sanitation, and unequal dental services increase both infection prevalence and cardiovascular risk. Public health policies that integrate infection control, vaccination where appropriate, and inflammation-targeted therapies offer complementary paths to reduce cardiovascular morbidity and mortality.