Evaluation of Changes Over Time in the Drug Burden and Medication Regimen Complexity in ESRD Patients Before and After Renal Transplantation

Background: Medication regimen complexity (MRC) has not been characterized in detail in patients with end-stage renal disease (ESRD). The objective of the present study was to quantify changes over time in the prescription drug burden and MRC in patients with ESRD (before transplantation, on discharge after kidney transplantation [M0], and 4 months [M4] and 12 months [M12] afterward).

Methods: We retrospectively studied adult patients having undergone kidney transplantation. The number and types of drug prescribed, the pill burden, and the MRC index (MRCI) at 4 different time points (before transplantation, M0, M4, and M12) were extracted from the patients' medical records. MRCI was calculated by adding each drug score (calculated according to its formulation, dosing frequency, and additional instructions concerning administration). Hence, the MRCI took account of all prescription drugs. A logistic regression model was used to identify factors associated with an elevated MRCI at M12.

Results: The median (interquartile range) age of the 354 study participants was 52 years (42-62). Respectively 21%, 42%, 53%, and 38% of the patients were taking 10 or more drugs before transplantation and at M0, M4, and M12. At M12, the 3 most frequently prescribed drug classes were immunosuppressants, cardiovascular system drugs, and drugs acting on the alimentary tract and metabolism. The pill burden and MRCI before transplantation were significantly lower (P < 0.001) than at each time point after transplantation. Diabetes and dyslipidemia were independently associated with an elevated MRCI at M12.

Conclusion: In kidney transplant recipients, the drug burden and MRCI were greater at all time points after transplantation than before transplantation. The impact of the drug burden and MRC on medication adherence and clinical outcomes in these patients requires further evaluation.