Medical management of heart failure (HF) has evolved and has achieved significant survival benefits, resulting in highly complex medication regimens. Complex medication regimens create challenges for older adults, including nonadherence and increased adverse drug events, especially associated with cognitive impairment, physical limitations, or lack of social support. However, the association between medication complexity and patients' health outcomes among older adults with HF is unclear. The purpose of this review is to address how the complexity of HF medications has been assessed in the literature and what clinical outcomes are associated with medication regimen complexity in HF. Further, we aimed to explore how older adults were represented in those studies. The Medication Regimen Complexity Index was the most commonly used tool for assessment of medication regimen complexity. Rehospitalization was most frequently assessed as the clinical outcome, and other studies used medication adherence, quality of life, healthcare utilization, healthcare cost, or side effect. However, the studies showed inconsistent results in the association between the medication regimen complexity and clinical outcomes. We also identified an extremely small number of studies that focused on older adults. Notably, current medication regimen complexity tools did not consider a complicated clinical condition of an older adult with multimorbidity, therapeutic competition, drug interactions, or altered tolerance to the usual dose strength of the medications. Furthermore, the outcomes that studies assessed were rarely comprehensive or patient centered. More studies are required to fill the knowledge gap identifying more comprehensive and accurate medication regimen complexity tools and more patient-centered outcome assessment.
© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.