BackgroundThis study aimed to determine whether de novo, prolonged-release tacrolimus- (PR-tacro) based immunosuppressive regimen affected graft and patient survival when compared to an immediate-release, twice-daily, tacrolimus- (IR-tacro) based regimen in kidney transplant recipients. We also aimed to determine the difference between the frequency of side effects, including diabetes control, in study groups. MethodsA total of 115 standard risk kidney transplant recipients were enrolled in this single center, retrospective study. Fifty-two patients received PR-tacro and 63 patients received IR-tacro as a calcineurin inhibitor. The primary outcome measures included incidence of graft loss and delayed graft function (DGF), biopsy-proven acute rejection , graft and patient survival, and creatinine clearance. Secondary outcome measures included the incidence of non-adherence, drug-induced tremor; post-transplant diabetes mellitus diagnosis rate; and control of diabetes in pre-transplant diabetic patients. ResultsBaseline characteristics and mean tacrolimus trough levels were comparable between groups. Incidence of graft loss, DGF, and graft and patient survival were similar between groups (P > .05). Mean creatinine clearance level was also similar (P > .05). Mean serum levels of fasting glucose (P < .05) and A1C (P < .05) were lower in PR-tacro group when compared to IR-tacro group. Post-transplant diabetes mellitus diagnosis rate was also lower in PR-tacro group when compared to IR-tacro group (P = .040). ConclusionThis study suggests that there is no statistically significant difference between PR-tacro and IR-tacro in terms of patient and graft survival, DGF, and biopsy-proven acute rejection rates in kidney transplant recipients. Post-transplant diabetes mellitus frequency is lower in non-diabetic patients, and glucose metabolism control is better in diabetic patients.