The clearance of low-density lipoprotein (LDL) isolated from uremic patients (autologous-LDL) and from a control subject (control-LDL) was studied in 12 uremic patients on conservative management and compared to the LDL clearance in control subjects. The clearances of autologous-LDL and control-LDL were almost the same in the patients. However, the fractional catabolic rate (FCR) of the autologous-LDL (0.307 +/- 0.094 pools/day, mean +/- SD) and the control-LDL (0.289 +/- 0.081 pools/day) were significantly lower (P < 0.05 and P < 0.01, respectively) than the FCR for LDL in the control subjects (0.376 +/- 0.045 pools/day). Moreover, one-half of the patients had an abnormally low LDL clearance rate ranging from 0.146 to 0.282 pools/day. The FCR for the autologous-LDL varied from 0.146 to 0.416 pools/day between the patients and was negatively related (r = -0.68, P = 0.02) to the serum urea concentration (from 11.8 to 39.2 mmol/liter) and tended to correlate positively with the glomerular filtration values (from 9.2 to 48.3 ml/min/1.73 m2; r = 0.57, P = 0.096, non-linear relationship). In conclusion, the clearance of LDL in patients with advanced uremia on conservative management is frequently decreased. This alteration in the metabolism of the most atherogenic particle in plasma may contribute to the accelerated atherosclerosis in uremic patients.