Screening for Medication-Regimen Complexity Before Transitions Between Care Settings: A Clinical Review

Abstract

Transitions between care settings represent critical junctures in patient management, where the risk of medication errors and adverse outcomes is heightened, particularly in populations with complex medication regimens. Screening for medication-regimen complexity prior to such transitions is vital for optimizing outcomes, reducing adverse drug events, and supporting safe continuity of care. This review synthesizes recent evidence and clinical guidelines to provide a comprehensive overview of the epidemiology, mechanisms, risk factors, clinical features, diagnostic strategies, management approaches, emerging therapies, and recommendations related to medication-regimen complexity screening. The article offers practical insights into implementing evidence-based screening protocols to enhance patient safety and healthcare quality during care transitions.

Introduction

The movement of patients between different care settings—such as hospital to home, hospital to skilled nursing facility, or between specialties—poses significant challenges in medication management. Complex regimens, polypharmacy, and discrepancies in medication lists frequently lead to adverse drug events (ADEs) and readmissions. The concept of medication-regimen complexity encompasses factors such as the number of medications, dosing frequency, administration instructions, and potential for drug-drug interactions. Proactive screening and identification of high-complexity regimens before transitions can enable targeted interventions, medication reconciliation, and patient education, thereby improving outcomes and reducing healthcare costs. This review addresses the importance of systematically assessing medication-regimen complexity and provides a framework for clinicians to integrate this practice into transitional care workflows.

Epidemiology / Disease Burden

Medication errors during transitions of care are a leading cause of preventable harm in healthcare systems worldwide. Studies indicate that up to 60% of medication errors occur during care transitions, with older adults and patients with multiple comorbidities being particularly vulnerable. The prevalence of polypharmacy (use of five or more medications) in hospitalized patients exceeds 50% in some populations, and each additional medication adds to regimen complexity and risk. Adverse drug events resulting from complex regimens are associated with increased hospitalizations, prolonged length of stay, and higher mortality rates. The burden is particularly pronounced in chronic disease populations, such as heart failure, diabetes, and chronic obstructive pulmonary disease, where medication regimens are inherently multifaceted.

Pathophysiology

The pathophysiological basis for adverse outcomes related to medication-regimen complexity lies in the interplay of pharmacokinetics, pharmacodynamics, and patient-specific factors. Complex regimens increase the cognitive load on patients and caregivers, leading to suboptimal adherence, unintended omissions, and dosing errors. Polypharmacy elevates the risk of drug-drug and drug-disease interactions, which can alter therapeutic efficacy and precipitate adverse effects. In elderly patients, age-related changes in renal and hepatic function further compound these risks. The lack of standardized communication between care settings exacerbates discrepancies and errors, underscoring the need for systematic complexity screening.

Risk Factors

Key risk factors for high medication-regimen complexity include advanced age, multiple chronic conditions, cognitive impairment, limited health literacy, and socioeconomic barriers. Polypharmacy, frequent regimen changes, use of high-risk medications (e.g., anticoagulants, insulin, opioids), and complex dosing schedules further increase the risk. Transitions involving acute care settings and patients with recent hospitalizations are particularly prone to medication discrepancies and errors. Recognizing these risk factors is essential for prioritizing patients who would benefit most from complexity screening and targeted interventions.

Clinical Features

Patients with complex medication regimens often present with non-specific symptoms such as confusion, dizziness, falls, or gastrointestinal disturbances, which may be manifestations of suboptimal adherence or adverse drug reactions. In the context of care transitions, unintentional non-adherence, duplications, omissions, and inappropriate continuation or discontinuation of medications are common clinical features. These issues may not be immediately apparent without structured assessment tools, further highlighting the clinical importance of pre-transition screening.

Diagnosis

Assessment of medication-regimen complexity is facilitated by validated tools such as the Medication Regimen Complexity Index (MRCI), which quantifies complexity based on the number of medications, dosage forms, dosing frequency, and additional instructions. Structured medication reconciliation, involving multidisciplinary teams, is a cornerstone of diagnosis. Electronic health records (EHRs) with integrated clinical decision support systems can aid in flagging potentially complex regimens and discrepancies. Comprehensive assessment should also include patient interviews to identify barriers to adherence and understanding.

Treatment & Management

Management strategies focus on simplifying regimens, optimizing therapeutic choices, and enhancing patient education. Deprescribing unnecessary medications, consolidating dosing schedules, and selecting medications with favorable safety profiles are key interventions. Pharmacists play a pivotal role in regimen review, reconciliation, and patient counseling. Multidisciplinary transitional care programs that incorporate medication complexity screening have demonstrated reductions in ADEs, readmissions, and healthcare costs. Tailored discharge plans and follow-up enhance adherence and patient outcomes.

Recent Advances / Emerging Therapies

Recent advances include the integration of machine learning algorithms into EHRs to automate identification of high-risk regimens and predict adverse outcomes. Digital health tools, such as medication management apps and telepharmacy consultations, support ongoing monitoring and adherence. Pharmacogenomic testing is emerging as a tool to individualize therapy and reduce regimen complexity by selecting optimal agents and dosages. Collaborative care models that embed pharmacists in transitional care teams have shown promise in pilot studies, further supporting the value of comprehensive screening and intervention.

Guideline Recommendations

Major clinical guidelines, including those from the American Society of Health-System Pharmacists and the Institute for Healthcare Improvement, recommend systematic medication reconciliation and assessment of regimen complexity during all care transitions. Guidelines call for the use of validated assessment tools, involvement of multidisciplinary teams, and incorporation of patient-centered approaches. Education of patients and caregivers, clear communication between providers, and timely follow-up are emphasized as critical components of safe transitions. Implementing these recommendations is associated with improved clinical outcomes and higher patient satisfaction.

Conclusion

Screening for medication-regimen complexity prior to transitions between care settings is a clinically significant strategy to reduce medication errors, adverse drug events, and readmissions. Evidence-based protocols, multidisciplinary collaboration, and the use of validated assessment tools are essential for effective implementation. Recent technological advances and guideline-driven approaches provide a robust framework for integrating complexity screening into transitional care, ultimately enhancing patient safety and healthcare quality. Ongoing research and quality improvement initiatives are needed to further refine strategies and optimize outcomes for patients at risk.