The progression of lower limb atherosclerosis is associated with IgA antibodies against Chlamydia pneumoniae.

Abstract

to study the influence of serologically diagnosed chronic infection with Chlamydia pneumoniae on the progression of lower limb atherosclerosis in a group of disposed men. the highest systolic brachial and lowest systolic ankle blood pressures were followed for an average of 2.7 years in 129 men aged 65-73 years with conservatively treated small abdominal aortic aneurysms. Blood samples were taken to measure low-density lipoprotein and IgA and IgG titres of antibodies against C. pneumoniae by a microimmunofluorescence test. the prevalences of seropositivity varied from 43 to 83% depending on the definition. The ankle-brachial blood pressure index of the IgA-seropositive [corrected] men decreases by 11%, while it decreased by 4.8% among IgA-seronegative men (p<0.05). The significant difference persisted in a multiple-regression analysis adjusting for age, smoking, initial systolic ankle BP, and initial brachial systolic or diastolic BP, but disappeared after adjusting for the level of low-density lipoprotein. C. pneumoniae infection is associated with the progression of atherosclerosis.