1. Serum total sialic acid concentration, recently shown to be a cardiovascular risk factor, and also serum lipid-associated sialic acid concentration were measured in 15 patients with hypertriglyceridaemia (fasting serum triacylglycerol concentration > 2.3 mmol/l) showing a Frederickson's type IIB phenotype, 15 patients with hypercholesterolaemia showing a IIA phenotype and 15 age- and sex-matched normal control subjects.
2. Total serum sialic acid concentration was significantly raised in the hypertriglyceridaemic group (84.9 ± 21.5 versus 64.9 ± 20.8 mg/dl, P<0.03, Mann—Whitney U-test) compared with the normal control group, as was serum lipid-associated sialic acid concentration (23.0 ± 4.3 versus 12.0 ± 3.2 mg/dl, respectively, P<0.001, Mann—Whitney U-test).
3. Serum total sialic acid concentration was also significantly elevated in the hypertriglyceridaemic group as compared with the IIA phenotype hypercholesterolaemic group (84.9 ± 21.5 versus 58.4 ± 11.7 mg/dl, P<0.03, Mann—Whitney U-test), as was serum lipid-associated sialic acid concentration (23.0 ± 4.3 versus 14.9 ± 4.7 mg/dl, P<0.001, Mann—Whitney U-test).
4. We suggest that serum concentrations of both total sialic acid and lipid-associated sialic acid may be useful markers of cardiovascular risk which could, in part, be related to hypertriglyceridaemia.