Prevalence of Helicobacter pylori, cytomegalovirus, and Chlamydia pneumoniae immunoglobulin seropositivity in coronary artery disease patients and normal individuals in North Indian population.

Background: In present day atherosclerosis is perceived as a chronic inflammatory vascular condition and infectious diseases are believed to contribute to its pathophysiology. In this context, the microorganisms which are believed to play a role in the pathophysiology include Chlamydia pneumoniae, cytomegalovirus (CMV), and Helicobacter pylori.

Method: A case control study (retrospective) was conducted over a two-year period. The study population was divided into two groups with 200 individuals in each group. The first group comprised cases of coronary artery disease (CAD) and the second comprised healthy controls selected from the general population after matching for age and sex. Enzyme-linked immunosorbent assay (ELISA) was done for immunoglobulin (IgG) antibodies to H. pylori, C. pneumonia, and CMV. They were also evaluated for conventional risk factors including hypertension, diabetes, obesity, and dyslipidaemia. Epi Info™ version 6 six software was used for analysis of data. Odds ratio, χ(2) for trend and multiple logistic regression analysis were used to find out statistically significant results.

Results: Seropositivity for H. pylori was present in 119 patients of CAD (59.5%) but it was present in only 76 controls (38%) (P = 0.001). There was a statistically significant association between seropositivity for H. pylori and CAD. There was no statistically significant association between C. pneumoniae and CMV seropositivity with CAD. Multiple logistic regression analysis was done with CAD as the outcome (dependent variable). The predictor covariates (independent) variables were seropositivity to H. pylori, C. pneumoniae, and CMV, hypertension, obesity, diabetes, and dyslipidaemia. It was found that seropositivity to H. pylori, hypertension, obesity, and dyslipidaemia were significant risk factors for CAD.

Conclusion: Our study shows an association between IgG antibody response to H. pylori and CAD. Multiple logistic regression analysis showed that this association was retained even on comparison with the other risk factors.