Influence of hypercholesterolemia on patient and graft survival in recipients of kidney transplants.

AIM: The aim of this retrospective, single centre study, was to study the effect of pre- and post-transplant serum total cholesterol (TC) on patient and graft survival. We also sought to see whether patients who had very high TC (>8 mmol/L) had a higher incidence of graft failure and patient mortality compared with those whose cholesterol was only moderately elevated.

METHODS

Records of 935 cadaver kidney transplants between 1984 and 1998 were examined. Patients were placed into three groups based on TC level: <5.5 mmol/L (group 1), 5.5-8 mmol/L (group 2) and >8 mmol/L (group 3). The mean TC value from the first five post-transplant years was taken to seek a correlation between TC and post-transplant events.

RESULTS

The mean graft follow-up was 66.9 +/- 50.1 months, ranging from 0.1 to 191 months, while mean patient follow-up was 83.8 +/- 50.1 months, ranging from 0.5 to 191.6 months. Pre-transplant TC was available in 201 patients (21.5%), and post-transplant data was available (for first 5 yr) in 655 patients (70%). During the study period, 220 patients (23.5%) had died, 285 (30.5%) of the grafts had failed during the follow-up, while 129 (13.8%) of the patients died with a functioning graft. We found significantly longer survival of patients having a pre-transplant TC below 5.5 mmol/L vs. patients whose pre-transplant TC was above 5.6 mmol/L (p = 0.02). We also compared patients who had very high pre-transplant TC (>8 mmol/L) level with those whose TC was moderately elevated (5.5-8 mmol/L) and found that there was no higher incidence of graft failure (p = 0.77) nor patient mortality (p = 0.83). No difference could be found in graft survival based on pre-transplant TC. We also did not find a detrimental influence of post-transplant TC on the patient or graft survival. Diabetes mellitus (p = 0.006) and age over 50 yr (p = 0.007) affected patient survival, while low cyclosporine levels (p = 0.02) and acute rejection episodes (p = 0.009) affected graft survival. The mode of dialysis and time on dialysis prior to transplantation did not affect patient and graft survival.

CONCLUSIONS

We found significantly greater survival of patients having a pre-transplant TC below 5.5 mmol/L. No difference could be found in graft survival based on pre-transplant TC. Post-transplant TC did not adversely affect patient or graft survival.