Cardiovascular disease in renal allograft recipients is associated with elevated sialic acid or markers of inflammation

BACKGROUND: Cardiovascular disease (CVD) is more common in patients with renal failure, even after renal transplantation. We wished to examine the relationship between markers of inflammation and CVD in stable renal transplant patients. METHODS: Ninety stable renal transplant outpatients with no recent illnesses or rejection were invited for study. Blood was drawn for a variety of inflammatory markers including total plasma sialic acid (SA) levels. RESULTS: Patients with CVD were significantly older than patients without (54 +/- 12 vs. 42 +/- 14 yr, p < 0.01) and had significantly lower total cholesterol (4.5 +/- 1.6 vs. 5.1 +/- 1.0 mmol/L, p < 0.01). Time from transplantation, present creatinine and blood pressure, smoking history were similar in both groups. Patients with CVD had significantly higher levels of SA (89.2 +/- 22.3 vs. 77.4 +/- 13.9 mg/dL, p = 0.01); fibrinogen [4.6 (2.2-6.7) vs. 3.6(1.9-5.7) g/L; p = 0.05); and C-reactive protein (CRP) [2.2 (1.5-8.0) vs 1.5 (0.7-3.0) microg/dL] than those without CVD. A logistic multiple linear regression analysis of the data with CVD as the dependent variable, and all the other parameters as independent variables, showed significant associations (F = 16.9; p < 0.001) with diastolic blood pressure (beta = 5.6; p = 0.02) and CRP (beta = 4.4; p = 0.04). CONCLUSIONS: This study suggests that inflammation is associated with a higher prevalence of cardiovascular disease in patients with renal allografts. The measurement of sialic acid as a risk factor may be superior to that of CRP in this group as its concentration is independent of renal function.