Inverse association of Chlamydia pneumoniae infection with high blood pressure in Japanese adults

To determine whether Chlamydia pneumoniae (C. pneumoniae) infection is asso ciated with hypertension in Japanese adults, we measured serum levels of Ig A (a marker of reinfection) and of IgG (a marker of previous infection) ant ibodies to C. pneumoniae by enzyme-linked immunosorbent assay in 112 adults including normotensive and untreated hypertensive subjects and in 117 hype rtensive subjects who had been receiving treatment for more than 3 years. I n 112 adults, positivity rate for IgA was lower (P < .01) in hypertensive t han in normotensive or borderline hypertensive subjects. Positivity rates f or IgA and IgG together, which indicate persistent infection of C. pneumoni ae, were lower (P < .01) in hypertensive than in normotensive subjects. IgA levels were inversely correlated with systolic blood pressure (SBP) (r=0.5 30, P=.0001) and with diastolic blood pressure (DBP) (r=0.398, P =.0001). I n the 117 hypertensive subjects treated with medication, positivity rate fo r IgA was lower (P < .01) in subjects with poor control than in those with good control. Positivity rates for IgA and IgG together were lower (P <0.01 ) in the poor control group than in the good or fair control groups. IgA le vels were correlated inversely with SEP and DBP. In both 112 adults and 117 hypertensive patients, levels of SEP or DBP were inversely associated with positivity rates for IgA and IgG together in multiple logistic regression analysis. The results suggest an inverse relationship between high blood pr essure and C. pneumoniae infection in Japanese adults. (C) 2001 American Jo urnal of Hypertension, Ltd.