Increased serum levels of IgA and C4 in atherosclerosis: the absence of a correlation with the arteriographic picture

We have previously shown that an increase in serum IgA and C4 is often detectable in presence of diffuse atherosclerotic disease. The present study was performed to verify such results in a different and larger sample of subjects, and to ascertain whether the above immunologic variables are correlated with the severity of atherosclerotic disease. Seventy-three atherosclerotic subjects with at least 1 significant (> 75%) stenosis in a major arterial branch were selected according to the reports of arterial panangiographies performed previously. Among them, 36 subjects (24 men and 12 women, mean age 63 +/- 7 years) were singled out, who matched by age and sex 36 control subjects (mean age 63 +/- 7 years). In all of these subjects the following serum immunologic and lipid variables were measured: IgG, IgA, IgM, IgE, C3, C4, total cholesterol, HDL-cholesterol and triglycerides. With respect to the controls, the 36 matched atherosclerotic subjects had higher levels of IgA (263.0 +/- 119.8 vs 334.3 +/- 130.5 mg/dl; p = 0.0126), C4 (25.7 +/- 5.8 vs 30.4 +/- 9.1 mg/dl; p = 0.0297) and triglycerides (153.1 +/- 77.3 vs 209.7 +/- 141.3; p = 0.0500). No correlation was found between the number of arterial stenoses (range 1-8, mean 2.9 +/- 1.5) and any of the immunologic or lipid parameters in all the 73 atherosclerotic subjects. Only the daily cigarette consumption was correlated with the disease extension (tau = 0.1984; p = 0.0392).(ABSTRACT TRUNCATED AT 250 WORDS)