Progression of renal failure during the two years preceding maintenance dialysis

The respective contribution of sex, type of nephropathy, degree of proteinu ria, blood pressure, protein and sodium daily intake, lipid profile, protid emia, hemoglobinemia, acidosis and CaPO4 product on the rate of renal failu re progression is debated. The link between these parameters and the decrea se of creatinine clearance, Delta Ccr (according to Cockroft) was assessed in uni and multivariate analysis in a population of 49 patients (26 men, 23 women; age 60 +/- 15 years, weight 73 +/- 15 kg) selected out of 173 prese ntly treated hemodialysis patients on the basis of availability of a quarte rly follow-up for two years before starting dialysis. The patients were adv ised a moderate protein and salt restriction which could be retrospectively assessed (on urinary excretion of urea and sodium) at respectively 0.82 g/ kg/day and 6,5 g/day. The two years Delta Ccr was 14 +/- 14 mi/min. It was not different in men and women (specially when expressed in % of initial va lue). This decrease in Ccr was neither significantly different in glomerula r disease (17 +/- 8, n = 14), diabetic nephropathy (12 +/- 6, n = 7), nephr oangiosclerosis (15 +/- 8, n = 5), interstitial nephritis (12 +/- 10, n = 1 4), and PKD (11 +/- 12, n = 9). Patients with antihypertensive drugs (n = 4 2) had a faster progression than those without drugs (n = 7). Delta Ccr = 1 5 +/- 14 vs 7 +/- 7 ml/min (p < 0.05) in spite of comparable blood pressure but with higher proteinuria. linear regression of Delta Ccr with the initi al and two year averaged values of the quantitative parameters showed a sig nificant positive link for both values with cholesterol, hemoglobine and pr oteinuria and a negative one with protidemia. A positive link was observed with the initial value of bicarbonate and the two year mean of diastolic an d mean blood pressures. No link at ail was observed with urea and Na excret ion, CaPO4 product and triglycerides. Multiple regression disclosed a signi ficant link only for protidemia (negative with both initial and two years a veraged value), diastolic BP (only for the two year averaged value and hemo globinemia if or the initial value). When the patients were classified acco rding to a threshold value of their protidemia, DBP, hemoglobinemia, and ch olesterolemia those with the combination of two risk factors of progression (pro-tidemia < 66 g/l, DBP greater than or equal to 90 mmHg, hemoglobinemi a > 11 g/dl, proteinuria > 3 g/d, CT > 5 mmol/l) had a significantly greate r decrease of Ccr than those with the three other combinations at the excep tion of the association of low protidemia with DBP. Conclusion: 1. diastoli c hypertension and low protidemia are the two most important factors predic ting progression of renal failure; 2. a predictive synergy was furthermore pointed out between on one hand low protidemia and diastolic hypertension a nd on the other hand proteinuria and cholesterol; 3. on the contrary, anemi a attenuates progression linked to low protidemia, diastolic hypertension, proteinuria and high cholesterol.