Loss of residual renal function in patients on regular haemodialysis

The literature offers scant data on loss of residual renal function in chronic haemodialysis patients. The present study was undertaken in 34 patients, to evaluate residual creatinine clearances (CCr) before the start of haemodialysis and after 3, 12 and 24 months. CCr progressively declined from 6.15 +/- 2.61 (before) to 1.40 +/- 1.29 ml.min-1 (after 24 months: p less than 0.01). The decrease was largest during the first three months of dialysis therapy (slope -0.99 +/- 1.01 ml.min-1.month-1 for the first three months vs. -0.23 +/- 0.12 ml.min-1.month-1 for the entire 24-month period: p less than 0.01). The decline in CCr during the first three months was significantly more pronounced in glomerular disease than in tubulo-interstitial disease (p less than 0.05). This could not be attributed to differences in blood pressure, body weight or hypotensive medications. Age and sex also had no influence. Our data indicate that there is a characteristic progressive loss of renal function in haemodialyzed patients and that the early decline is most pronounced in patients with glomerular disease. Regular assessment of residual renal function at least every three months is indicated in patients starting chronic haemodialysis treatment.