Pulse pressure is an independent predictor of aortic stiffness in patients with mild to moderate chronic kidney disease.

BACKGROUND: In patients with end-stage renal disease pulse wave velocity (PWV) has been widely assessed, but its behavior in mild to moderate chronic kidney disease (CKD) has been less investigated. We evaluated PWV in mild to moderate CKD. METHODS: We studied 31 patients with grade II-IV CKD. Aortic PWV (aPWV), aortic and upper limb augmentation index, creatinine clearance, C-reactive protein, serum fibrinogen, interleukin-1, interleukin-6, tumor necrosis factor, albumin, total and high-density lipoprotein cholesterol and blood pressure were evaluated. RESULTS: aPWV (7.95 +/- 0.64 m/s), but not augmentation index was significantly higher (p = 0.03) in CKD patients than age-matched healthy subjects (aPWV: 6.24 +/- 0.43 m/s; upper limb: 32.8 +/- 1.9; aortic: 27.7 +/- 1.9). At univariate regression analysis, aPWV was significantly correlated with age (r = 0.44; p = 0.013), interleukin-6 (r = 0.43; p = 0.027), pulse (r = 0.39; p = 0.029), systolic blood pressure (r = 0.37; p = 0.038) and tumor necrosis factor (r = 0.39; p = 0.029). At multivariate analysis, pulse pressure was the only significant independent determinant (beta = 0.37; p = 0.05) of aPWV. CONCLUSION: The results of this study confirm an aPWV increase in mild to moderate CKD and emphasize association between pulse pressure and PWV, independently of renal failure.

Increased albumin and fibrinogen synthesis in hemodialysis patients with normal nutritional status.

This study compared the rates of whole-body proteolysis and of albumin and fibrinogen synthesis of seven hemodialysis patients (HD) with those of seven normal matched control subjects (C). HD patients had a normal nutritional and inflammatory status and serum albumin levels >3.5 g/dl. Endogenous leucine flux, albumin and fibrinogen fractional synthesis rate (FSR), and absolute intravascular synthesis rate (ASR) of albumin and fibrinogen all were evaluated by a primed/continuous infusion of 5,5,5-D3-L-leucine. Plasma volume was determined by the Evans blue dye dilution method. Endogenous leucine flux was significantly increased in HD (2.64 +/- 0.08 micromol/kg per min) compared with C (2.17 +/- 0.07 micromol/kg per min, P: < 0.05). Serum albumin concentrations were similar in HD and C. Plasma fibrinogen levels were significantly increased in HD compared with C (P: < 0.05). Plasma volume was greater in HD than in C (P: < 0.05). As a result, total intravascular pool of both albumin (141 +/- 7 versus 114 +/- 3 g/1.73 m(2), P: < 0.05) and fibrinogen (11.7 +/- 1 versus 6.7 +/- 0.5 g/1.73 m(2), P: < 0.05) were greater in HD than in C. Albumin FSR was not statistically different in HD and C. However, albumin ASR was significantly increased in HD than in C (13.7 +/- 2 versus 10.3 +/- 1 g/1.73 m(2) per d, P: < 0.05). Similarly, FSR of fibrinogen did not differ in HD and C groups, whereas ASR of fibrinogen was significantly higher in HD than in C (3.31 +/- 0.6 versus 1.94 +/- 0.3 g/1.73 m(2) per d, P: < 0.05). In summary, normoalbuminemic HD patients have an increased intravascular pool with a greater absolute synthesis rate of both albumin and fibrinogen and an increased rate of whole-body leucine flux.