Association of common chronic infections with coronary artery disease in patients without any conventional risk factors.

BACKGROUND & OBJECTIVES Report from the west suggest an association of infections and inflammation with atherosclerotic coronary artery disease (CAD). Entire microbial burden from several simultaneous chronic infections could be more important than a single infection in promoting atherosclerosis. No study has been done in Indian population, investigating the association of various chronic infections with CAD. We therefore evaluated the presence of markers of chronic infections in CAD patients having no conventional risk factors and healthy individuals in a tertiary care hospital in north India. METHODS Seropositivity to IgG antibodies was investigated for Chlamydia pneumoniae, Mycoplasma pneumoniae, and Helicobacter pylori in 30 CAD patients with no conventional risk factors scheduled for coronary artery bypass surgery and in healthy blood donors. Periodontal pathogens were isolated by aerobic and anaerobic culture. RESULTS All patients except one were < 55 yr of age and six were younger than 40 yr. Seropositivity to C. pneumoniae was significantly higher in CAD patients than healthy controls (63.3 vs. 23.3%, P<0.01). Combined seropositivity to both C. pneumoniae and M. pneumoniae was significantly higher in CAD patients with myocardial infarction (MI) than those without MI (61.5 vs. 11.8%, P<0.05). Aerobic and anaerobic cultures for the isolation of periodontal pathogens were positive in seven patients and five healthy blood donors. INTERPRETATION & CONCLUSION C. pneumoniae seropositivity was significantly higher (P<0.001) in CAD patients without any of the conventional risk factors for CAD. Combined seropositivity to C. pneumoniae and M. pneumoniae was significantly higher (P<0.05) in CAD patients with MI than in those without MI. Possibly CAD in young is not (or less) governed by conventional risk factors, and infectious agents can be potential risk factors for the development of atherosclerosis and CAD in this subset of patients.