Chronic infections and the risk of carotid atherosclerosis - Prospective results from a large population study

Background-Chronic infections have been implicated in the pathogenesis of a therosclerosis, yet from an epidemiological perspective, this concept remai ns controversial. Methods and Results-The Bruneck Study is a prospective population-based sur vey on the pathogenesis of atherosclerosis, In 826 men and women 40 to 79 y ears old (1990 baseline), 5-year changes in carotid atherosclerosis were th oroughly assessed by high-resolution duplex scanning. The presence of chron ic respiratory, urinary tract, dental, and other infections was ascertained by standard diagnostic criteria. Chronic infections amplified the risk of atherosclerosis development in the carotid arteries. The association was mo st pronounced in subjects free of carotid atherosclerosis at baseline (age- /sex-adjusted odds ratio [95% CI] for any chronic infection versus none, 4. 08 [2.42 to 6.85]; P<0.0001) and applied to all types of chronic (bacterial ) infections. It remained independently significant after adjustment for cl assic vascular risk attributes and extended to low-risk individuals free of conventional risk factors. Among subjects with chronic infections, atheros clerosis risk was highest in those with a prominent inflammatory response. Markers of systemic inflammation, such as soluble adhesion molecules and ci rculating bacterial endotoxin, and levels of soluble human heat-shock prote in 60 and antibodies to mycobacterial heat-shock protein 65 were elevated i n subjects with chronic infections and predictive of an increased risk of a therosclerosis, Conclusions-The present study provides solid evidence for a role of common chronic infections in human atherogenesis. Induction of systemic inflammati on and autoimmunity may be potential pathophysiological links.