Renal transplant patient compliance with free immunosuppressive medications

Background. Noncompliance with immunosuppressive medications after renal transplantation is believed to be a major cause of allograft rejection and graft loss, with the impressive costs of these agents considered a significant reason for noncompliance. Our purpose was to determine the compliance rates of renal transplant patients who received their immunosuppressant therapy free of charge and evaluate their patterns of compliance. Methods. All patients who received a renal transplant and received their immunosuppressant medications at our institution for their first year posttransplant were included in the study. Compliance rate was calculated and serum immunosuppressant concentrations were obtained to validate compliance assessments. Results. Eighteen patients were included in the study. Approximately 48% of noncompliant patients were found to have subtarget drug concentrations, although only 14% of compliant patients had subtarget levels (x²=12.9, P<0.001). At 5 months posttransplant, 95% of the patients remained compliant; however, by 12 months posttransplant, only 48% of the patients remained compliant. The mean time to the first non-compliant month was 9.8 months (95% confidence intervals=8.60-11.0). Conclusions. Patients who received their immunosuppressants free of charge were generally compliant within their first year of transplantation, however, compliance tended to decrease over time. This suggests that drug cost alone does not explain noncompliant behavior. Intensive efforts to increase medication compliance before month 8 posttransplantation should be implemented.