CHLAMYDIA-PNEUMONIAE ANTIBODIES IN SEVERE ESSENTIAL-HYPERTENSION

Several studies have implied an association between Chlamydic pneumoni ae (C. pneumoniae) and cardiovascular disease. Our study was designed to determine whether this organism is associated with severe essential hypertension in a multiracial British population. Antibodies to C. pn eumoniae were measured by microimmunofluorescence in 123 patients with chronic severe hypertension and 123 control subjects, matched for eth nic origin, age, sex, and smoking habit, admitted to the same hospital with various noncardiovascular, nonpulmonary disorders. Previous infe ction was defined by IgG 64 to 256, provided that there was no detecta ble IgM. Multiple regression analyses of matched and unmatched data we re used to investigate the influences of antibody levels and potential confounding factors (ethnic origin, age, sex, smoking habit, diabetes mellitus, and social deprivation) on hypertension. A portion of the h ypertensive patients underwent echocardiography, estimation of left ve ntricular mass index, and measurements of fibrinogen, D-dimer, and von Willebrand factor concentrations. Thirty-five percent of hypertensive patients and 17.9% of matched control subjects had antibody titers co nsistent with previous C. pneumoniae infection. The hypertensive patie nts differed significantly from their matched control subjects in thei r level of previous infection, with an odds ratio of 2.5 (95% confiden ce interval, 1.3 to 4.7). There were no significant differences in ant ibody levels between patients with left ventricular hypertrophy and th ose without it. Fibrinogen, D-dimer, and iron Willebrand factor concen trations were not significantly associated with antibody levels. These data support an association of C. pneumoniae with severe essential hy pertension. They provide no evidence of a predisposition to develop le ft ventricular hypertrophy in hypertensive patients with C. pneumoniae infection or of associations with hypercoagulability or endothelial d ysfunction.