Serum sialic acid as an indicator of change in coronary artery disease.

We measured serum levels of total sialic acid (TSA) by an enzymatic method in 74 men who completed the St Thomas' Atherosclerosis Regression Study (STARS). Coronary artery disease (CAD) was assessed as the change (delta) in mean absolute width of coronary segments (MAWS) over 3 years by a computerized technique. Delta TSA was significantly correlated with delta MAWS (r = -.50, P < .001) after adjusting for age, blood pressure, smoking status, and plasma low-density lipoprotein (LDL) cholesterol. The relative risk of progression of CAD for a delta TSA exceeding 10 mg/dL as compared with a delta TSA not exceeding 10 mg/dL was 4.6 (95% confidence interval, 2.4 to 8.7). We conclude that serial measurement of serum TSA levels may be a useful indicator of the progression of CAD.