This study examines the associations between medication adherence and burden, and health-related quality of life (HRQOL) in predialysis chronic kidney disease (CKD). A prospective study targeting adults with advanced CKD (estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m2) and not receiving renal replacement therapy was conducted in Tasmania, Australia. The actual medication burden was assessed using the 65-item Medication Regimen Complexity Index, whereas perceived burden was self-reported using a brief validated questionnaire. Medication adherence was assessed using a four-item Morisky-Green-Levine Scale (MGLS) and the Tool for Adherence Behaviour Screening (TABS). The Kidney Disease and Quality of Life Short-Form was used to assess HRQOL. Of 464 eligible adults, 101 participated in the baseline interview and 63 completed a follow-up interview at around 14 months. Participants were predominantly men (67%), with a mean age of 72 (SD 11) years and eGFR of 21 (SD 6) mL/min/1.73 m2. Overall, 43% and 60% of participants reported medication nonadherence based on MGLS and TABS, respectively. Higher perceived medication burden and desire for decision-making were associated with nonadherent behaviour. Poorer HRQOL was associated with higher regimen complexity, whereas nonadherence was associated with a decline in physical HRQOL over time. Medication nonadherence, driven by perceived medication burden, was prevalent in this cohort, and was associated with a decline in physical HRQOL over time.
Keywords: chronic kidney disease; health-related quality of life; medication adherence; medication burden; medication regimen complexity index.