Relationship between serum albumin and pulse wave velocity in patients on continuous ambulatory peritoneal dialysis

BACKGROUND Hypoalbuminemia is a risk factor for cardiovascular events and mortality in dialysis patients, but the underlying mechanism remains unclear. Meanwhile, increased pulse wave velocity (PWV), the marker of arterial stiffness, has been proved to be an independent predictor of cardiovascular disease. The relationship between serum albumin and PWV in continuous ambulatory peritoneal dialysis patients (CAPD) was studied. METHODS Sixty-two CAPD patients were studied. The average age was 63 +/- 12 years and dialysis duration was 23 +/- 22 months. Serum albumin, C-reactive protein (CRP), and carotidfemoral PWV were measured. RESULTS Among these patients, 43.5% were men. The mean serum albumin concentration was 37 +/- 4 g/L and PWV was 11.9 +/- 2.3 m/s. PWV positively correlated with age (r = 0.35, P < 0.01), diabetes (yes=1, no=0; r = 0.292, P < 0.05), systolic blood pressure (SBP; r = 0.493, P < 0.001) and CRP (r = 0.295, P < 0.05), but negatively correlated with serum albumin (r = -0.357, P < 0.01). In multiple regression analysis, SBP (beta = 0.615, P < 0.001), age (beta = 0.414, P < 0.01), albumin (beta = -0.315, P < 0.05) and total cholesterol (beta = 0.275, P < 0.05) were independent determinants of PWV. In a non-inflamed subgroup (CRP < 3 mg/L, n=30), albumin still negatively correlated with PWV (r = -0.66, P < 0.001). CONCLUSION Serum albumin inversely correlated with increased PWV in CAPD patients, suggesting that increased arterial stiffness might be the link between hypoalbuminemia and increased cardiovascular mortality in dialysis patients.