Could Helicobacter pylori infection increase the risk of coronary heart disease by modifying serum lipid concentrations?

OBJECTIVE: To investigate the relation between Helicobacter pylori infection and coronary heart disease (CHD). DESIGN: A case-control study. SETTING: Northern Finland (about 650,000 inhabitants). PATIENTS: 116 patients with angiographically documented CHD and 116 controls matched for age and gender randomly recruited from the register of the Finnish Social Insurance Institute. MAIN OUTCOME MEASURES: The odds ratio (OR) estimates for the association of H pylori infection with CHD. RESULTS: 64% of the CHD patients and 53% of the controls were seropositive for H pylori; the OR adjusted for age and gender was 1.5 (95% confidence interval (CI) 0.9 to 2.5). An additional adjustment for the common risk factors of CHD, including lipid concentrations, in a logistic regression analysis produced an OR estimate of 1.1 (95% CI 0.6 to 2.1). Among the controls, those who were H pylori positive had significantly (P = 0.03) higher concentrations of serum triglycerides than those who were H pylori negative: the trend among the cases was similar, but non-significant. The concentrations of HDL cholesterol tended to be lower in those who were H pylori positive than in those who were H pylori negative, among both the cases and the controls. CONCLUSIONS: The impact of H pylori infection as an independent risk factor for CHD seems to be minor. On the other hand the results are consistent with the hypothesis that H pylori infection might modify the serum lipid concentrations in a way that could increase the risk of CHD.