Infection with Chlamydia pneumoniae but not Helicobacter pylori is related to elevated apolipoprotein B levels.

OBJECTIVE

Results of many studies show that apolipoprotein B (apo B) is a better marker of risk of vascular disease than other lipid markers including LDL and HDL-cholesterol and triglycerides. We investigated the association between two infectious agents: C. pneumoniae and H. pylori, known to have an atherogenic effect, and apo B, to evaluate the effects of chronic infections on apo B levels.

METHODS AND

RESULTS

The study group consisted of 257 patients in whom diagnostic coronary angiography was performed. C. pneumoniae IgG and IgM and H. pylori IgG and IgA antibodies were measured by enzyme-linked immunosorbent assay and apo B levels were measured by the nephelometry method. Established risk factors of atherosclerosis were recorded. Of 257 patients recruited, 104 had normal vessels, 88 had 3 or more vessels obstructed and 65 had ectatic vessels without atherosclerosis. Mean apo B concentration was significantly higher in C. pneumoniae IgG and IgM positive healthy subjects compared with C. pneumoniae negatives (0.954 vs. 0.722 and 0.973 vs. 0.851, p < 0.001 and p = 0.007, respectively). Apo B levels were significantly higher in severe atherosclerotic patients (0.985 +/- 0.234 g/l) compared with control subjects (0.892 +/- 0.244 g/l) (p = 0.008), but the difference was not significant in ectatic subjects (0.946 +/- 0.272 g/l) when compared with controls (p = 0.18). Apo B levels were higher but not statistically significant in H. pylori antibody positive cases when compared with negatives.

CONCLUSIONS

Apo B levels increased with C. pneumoniae infection. This finding supports the hypothesis that lipid profiles change to atherogenic lipid profile in chronic infections.