C-reactive protein levels and prevalence of chronic infections in subjects with hypoalphalipoproteinemia

Low levels of high-density lipoprotein cholesterol (HDL-C) show a consistent relationship with the development of atherosclerosis. The underlying mechanisms are not well understood, but recent studies in subjects with primary hypoalphalipoproteinemia suggest that this could represent a proinflammatory condition. To better assess the link between HDL-C levels and C-reactive protein levels and the possible role of chronic infections as putative mediators of this relationship, we studied a population sample with nonselected causes of hypoalphalipoproteinemia. Eighty-six consecutive patients with HDL-C levels below 40 mg/dL who attend our lipid clinic and 86 control subjects with normal concentrations matched for gender, age, smoking habit, and weight were included in the study. Mean HDL-C levels were 34 ± 3.9 and 55.4 ± 8.8 mg/dL for subjects with hypoalphalipoproteinemia and control subjects, respectively. C-reactive protein concentrations were increased in case patients as compared with control subjects (2.13 ± 2.0 vs 1.52 ± 1.8 mg/L; P = .025). The prevalence of herpes simplex virus type 1, cytomegalovirus, Chlamydia pneumoniae, and Helicobacter pylori infections did not differ between the 2 groups. Although a possible confounding variable could be a degree of insulin resistance within the group of patients with low HDL-C levels, our results indicate that C-reactive protein levels are increased in subjects with nonselected hypoalphalipoproteinemia and that chronic infections do not appear to mediate this relationship.