Effects of diabetes and cadaveric organs on functional performance and health-related quality of life after kidney transplantation

Background: The current study was undertaken to identify factors specific to kidney transplantation that are associated with posttransplant functional performance (FP) and health-related quality of life (HRQOL). Methods: Karnofsky FP status was assessed longitudinally in 86 adult kidney transplant recipients. Patients reported HRQOL using the Short Form-36 (SF-36) health survey and the Psychosocial Adjustment to Illness Scale (PAIS). Results: FP improved (P <0.001) after kidney transplantation (from 75 ± 1 to 77 ± 1, 81 ± 1, and 82 ± 1 at 0, 3, 6, and 12 months, respectively). Patients receiving organs from living donors showed continued improvement through posttransplant year 1 while those receiving cadaveric organs stabilized at month 6 (simple interaction contrast, year 1 versus pretransplant; P <0.05). Patients receiving dialysis therapy for 6 months or more prior to transplantation demonstrated lower SF-36 posttransplant physical component scores in comparison with patients who were transplanted preemptively (38 ± 1 versus 45 ± 2, P <0.05). Path analysis demonstrated the positive direct effect of time on FP with kidney transplantation (β = 0.23, P <0.05), and the negative direct effects on FP of diabetes (β = -0.22) and cadaveric organs (β = -0.22, both P <0.05). In turn, FP had a positive direct effect on HRQOL (β = 0.40, P <0.001). Conclusions: Overall improvement in FP is attenuated 1 year after kidney transplantation in recipients of organs from cadaveric donors. The positive effect of time after transplantation, and the negative effects of cadaveric organs and diabetes on posttransplant HRQOL, are indirect and are mediated by the direct effects of these variables on posttransplant FP.