Evaluation of Adherence to Immunosuppressive Drugs in Kidney Transplantation by Control of Medication Dispensing

Nonadherence to immunosuppressive medications represents a burden to organ transplantation being associated with rejection episodes and graft loss. In this cross-sectional study we evaluated the prevalence and risk factors for nonadherence in kidney transplant patients by measuring the retrieval of the immunosuppressive drugs in the registry kept by the state Rio Grande do Sul public health system. We considered nonadherence the failure to retrieval of medication at least one time over a 1-year period of evaluation. In 288 patients evaluated, the frequency of failure to retrieve was 58.7%. Being fully employed (66.4% x 33.6%, P = .008) and younger age at transplantation (39 +/- 13 x 46 +/- 11, P = .011) were associated with nonadherence. Multivariate analysis showed a greater prevalence ratio (PR) of non- adherence in patients using tacrolimus. Estimated glomerular filtration rate was significantly lower in the nonadherence groups as compared with adherent groups (45.3 +/- 21.6 x 51.3 +/- 19.4, P = .016). In conclusion, we found a high prevalence of nonadherence to immunosuppressive drugs with association to active working situation and use of tacrolimus. Importantly, glomerular filtration rate was found to be lower in nonadherent patients.