Risk factors of renal failure progression two years prior to dialysisis

Aim: The respective contribution of sex, type of nephropathy, degree of pro teinuria, blood pressure, protein and sodium daily intakes, blood lipid pro file, protidemia, hemoglobinemia, acidosis and CaPO4 product on the rate of renal failure progression is debated. Patients and methods: The link betwe en these parameters and the decrease of creatinine clearance, Delta Ccr (ac cording to Cockroft) was assessed in uni- and multivariate analysis in a po pulation of 49 patients (26 women; age 60 +/- 15 years, weight 79 +/- 15 kg ) selected out of 173 presently treated hemodialysis patients on the basis of availability of a quarterly follow-up for 2 years before starting dialys is. The patients were advised a moderate protein and salt restriction which could be retrospectively assessed ton urinary excretion of urea and sodium ) at, respectively, 0.82 g/kg/day and 6.5 g/day. Results: The 2-year Delta Ccr was 14 +/- 14 ml/min. It was not different in men and women. This decre ase in Ccr was neither significantly different in glomerular disease (17 +/ - 8, n = 14), diabetic nephropathy (12 +/- 6, n = 7), nephroangiosclerosis (15 +/- 8, n = 5), interstitial nephritis (12 +/- 10, n = 14), and PKD (11 +/- 12, n = 9). Patients with antihypertensive drugs (n = 42) had a faster progression than those without drugs (n = 7): Delta Ccr = 15 +/- 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 initial and 2-year av eraged values of the quantitative parameters showed a significant positive link for both values with cholesterol, hemoglobine and proteinuria and a ne gative one with protidemia. A positive link was observed with the initial v alue of bicarbonate and the 2-year mean of diastolic and mean blood pressur es. No link at all was observed with urea and Na excretion, CaPO4 product a nd triglycerides. Multiple regression disclosed a significant link only for protidemia (negative with both initial and 2-year averaged value), diastol ic BP (only for the 2-year averaged value and hemoglobinemia (for the initi al value). When the patients were classified according to a threshold value of their protidemia, DBP, hemoglobinemia, and cholesterolemia those with t he combination of 2 risk factors of progression (protidemia greater than or equal to 66 g/l, DBP greater than or equal to 90 mmHg, hemoglobinemia > 11 g/dl, proteinuria greater than or equal to 3 g/d, CT > 5 mmol/l) had a sig nificantly greater decrease of Ccr than those with the 3 other combinations at the exception of the association of low protidemia with DBP. Conclusion : Diastolic hypertension and low protidemia are the 2 most important factor s predicting progression of renal failure. A predictive synergy was further more pointed out between low protidemia or diastolic hypertension with prot einuria and cholesterol. On the contrary anemia attenuates progression link ed to low protidemia, diastolic hypertension, proteinuria and high choleste rol.