Systemic inflammatory parameters in patients with atherosclerosis of the coronary and peripheral arteries

Plasma concentration of markers of inflammation are increased in patients w ith atherosclerosis. However, it is unclear whether the pattern and magnitu de of this increase vary with the site and extent of disease. In 147 patien ts undergoing semiquantitative coronary angiography, we measured the acute- phase reactants C-reactive protein (CRP) or serum amyloid A (SAA); the proi nflammatory cytokine interleukin 6 (IL-6); the active and total fractions o f the anti-inflammatory cytokine transforming growth factor-beta (TGF-beta) ; the macrophage activation marker neopterin; and the infection marker proc alcitonin. Compared with 62 patients without either coronary artery disease (CAD) or peripheral artery disease (PAD), 57 patients with CAD but no PAD showed greater median CRP (0.4 versus 0.2 mg/dL, P=0.004) and IL-6 (3.8 ver sus 1.6 pg/mL, P=0.007) levels and a lower level of active-TGF-beta (57 ver sus 100 ng/mL, P=0.038). Moreover, CRP, IL-6, and neopterin levels showed a positive and the active TGF-beta level a negative correlation with the ext ent of coronary atherosclerosis. Compared with these 57 patients with CAD a lone, 15 patients with PAD and CAD had higher median levels of SAA (17 vers us 7 mg/mL, P=0.008), IL-6 (12 versus 4 pg/mL, P=0.002), neopterin (14 vers us 11 mg/dL, P=0.006), and total TGF-beta (11834 versus 6417 ng/L, P=0.001) . However, these strong univariate associations of markers of inflammation and atherosclerosis were lost in multivariate analysis once age, sex, and h igh density lipoprotein cholesterol or fibrinogen were taken into account. Increased plasma levels of CRP, SAA, IL-6, TGF-beta, neopterin, and procalc itonin constitute an inflammatory signature of advanced atherosclerosis and are correlated with the extent of disease but do not provide discriminator y diagnostic power over and above established risk factors.