A comparison of the effects of C2-cyclosporine and C0-tacrolimus on renal function and cardiovascular risk factors in kidney transplant recipients.

BACKGROUND: There are few data directly comparing the effects of two-hour postingestion monitored cyclosporine (C2-CsA) vs. trough-monitored tacrolimus (C0-Tac) on renal function and cardiovascular risk factors. METHODS: We studied 378 (202 C2-CsA vs. 176 C0-Tac) incident kidney transplant recipients in Toronto, Canada, from August 1, 2000 and December 31, 2003. Outcomes included changes in estimated glomerular filtration rate (eGFR at 1 and 6 months by modification of diet in renal disease four-variable equation), mean arterial pressure (MAP), total cholesterol (TC), and new-onset diabetes mellitus (NODM) at six months posttransplant. The independent effect of treatment/monitoring strategies on continuous outcomes and time-to-NODM was modeled using linear and Cox regression, respectively. RESULTS: Mean eGFR was 59.5 vs. 62.9 ml/min at one month and 50.6 vs. 61.2 ml/min at six months for C2-CsA vs. C0-Tac, respectively. Multiple linear regression revealed the slope of eGFR to be 0.93 ml/min/month lower in C2-CsA patients. This was equivalent to an adjusted average eGFR difference of 4.64 ml/min between months one and six posttransplant. There was no significant difference in average MAP and TC. In a stepwise multivariable Cox model and a propensity score analysis, there was no significant association between the type of treatment/monitoring strategy and time-to-NODM. CONCLUSIONS: There was a greater decline in eGFR for patients on C2-CsA (vs. C0-Tac) between one and six months posttransplant. However, MAP, TC, and the risk of NODM were comparable in both treatment/monitoring groups. The long-term impact of short-term reductions in eGFR as a function of the type of treatment/monitoring strategy requires further study.