Medication Review Standards in Multimorbidity: Evidence-Based Approaches for Clinical Practice

Abstract

Multimorbidity, defined as the coexistence of two or more chronic conditions in an individual, presents a significant challenge for modern healthcare systems globally. Medication review standards in the context of multimorbidity are crucial for optimizing therapeutic outcomes, minimizing adverse drug events, and improving patient quality of life. This review provides a comprehensive, evidence-based exploration of current standards and best practices for medication review in patients with multimorbidity, integrating recent clinical guidelines, epidemiological data, mechanistic insights, and practical recommendations for clinicians.

Introduction

The rising prevalence of multimorbidity, especially among aging populations, has led to increased polypharmacy and a greater risk of adverse drug reactions, drug-drug interactions, and therapeutic inefficacy. Medication review is a structured evaluation of a patient\'s medicines with the aim of optimizing medication use and improving health outcomes. In patients with multimorbidity, this process is particularly complex due to overlapping disease processes, multiple prescribers, and the necessity to balance benefits and risks across competing priorities. A systematic approach to medication review is essential for patient safety, adherence, and cost-effective care.

Epidemiology / Disease Burden

Multimorbidity affects an estimated 30-60% of adults over the age of 65, with wide variability depending on population characteristics, healthcare settings, and definitions employed. Epidemiological studies indicate that individuals with multimorbidity are at significantly higher risk for hospital admissions, increased healthcare utilization, and mortality. Polypharmacy, often defined as the use of five or more medications, is prevalent in this population and is directly linked to adverse drug events, decreased physical functioning, and increased frailty. The burden of multimorbidity is not confined to high-income countries; low- and middle-income nations are experiencing a rapid rise, straining healthcare resources and highlighting the global imperative for robust medication review processes.

Pathophysiology

The pathophysiological underpinnings of multimorbidity are complex and multifactorial, involving chronic inflammation, genetic predisposition, aging-related changes in pharmacokinetics and pharmacodynamics, and environmental exposures. These mechanisms contribute to the development of multiple, often interacting chronic diseases such as diabetes, cardiovascular disease, chronic kidney disease, and depression. The pharmacological challenge arises as each disease may alter drug absorption, distribution, metabolism, or excretion, leading to increased sensitivity or resistance to medications, unpredictable side effects, and variable therapeutic responses.

Risk Factors

Key risk factors for both multimorbidity and the associated medication-related problems include advanced age, lower socioeconomic status, polypharmacy, cognitive impairment, and reduced organ function. Additionally, patients transitioning between care settings, those with limited health literacy, and those lacking coordinated care are particularly vulnerable. The presence of one chronic disease often predisposes individuals to others through shared risk factors such as obesity, sedentary lifestyle, and smoking, further complicating medication management.

Clinical Features

Clinically, patients with multimorbidity present with a spectrum of symptoms that may be nonspecific or atypical compared to single-disease presentations. Common features include fatigue, functional decline, falls, and cognitive impairment, often compounded by medication side effects. Adverse drug reactions, therapeutic duplication, and drug-disease interactions are frequently encountered, highlighting the necessity for vigilant medication review. Clinical complexity is further increased by differing disease trajectories and priorities among patients, requiring individualized approaches to care.

Diagnosis

Diagnosing multimorbidity involves comprehensive clinical assessment, detailed medication history, and the use of validated tools such as the STOPP/START criteria and Beers Criteria, which help identify potentially inappropriate medications. Medication reconciliation – the process of creating the most accurate list of all medications a patient is taking – is fundamental. Assessment of renal and hepatic function, as well as pharmacogenomic considerations where available, are essential for tailoring medication regimens. Collaborative input from pharmacists, primary care, and specialist providers enhances diagnostic accuracy and facilitates timely identification of medication-related problems.

Treatment & Management

Effective management hinges on regular, systematic medication reviews that are patient-centered and evidence-based. Key principles include deprescribing unnecessary medications, prioritizing therapies with a favorable risk-benefit profile, and aligning treatment with patient goals and preferences. Shared decision-making and clear communication regarding the rationale for medication changes are critical. Non-pharmacological interventions, such as lifestyle modifications and psychosocial support, should complement pharmacotherapy. Documentation and follow-up are necessary to monitor for efficacy, safety, and adherence.

Recent Advances / Emerging Therapies

Recent advances include the integration of clinical decision support systems (CDSS) within electronic health records, which can flag potential drug-drug interactions, dosing errors, and guideline deviations in real time. Pharmacogenomics is emerging as a tool to personalize medication selection and dosing, particularly in polypharmacy. Interprofessional medication review clinics and telemedicine-based review services have demonstrated reductions in medication-related harm and hospitalizations. Artificial intelligence and machine learning are being explored for risk stratification and prediction of adverse drug events in complex multimorbid populations.

Guideline Recommendations

Current guidelines from bodies such as the National Institute for Health and Care Excellence (NICE), American Geriatrics Society, and European Society of Cardiology emphasize routine, structured medication review for all patients with multimorbidity, ideally every 6-12 months or whenever clinical status changes. Guidelines recommend the use of standardized tools, engagement of multidisciplinary teams, and prioritization of patient values. A focus on reducing inappropriate polypharmacy, enhancing adherence, and preventing adverse outcomes is universal. Education and training for clinicians in medication review methodologies are strongly endorsed to ensure consistent application of best practices.

Conclusion

Medication review standards in multimorbidity are foundational to safe, effective, and patient-centered care. As the prevalence of multimorbidity increases, clinicians must adopt evidence-based strategies to optimize medication regimens, minimize harm, and enhance outcomes. Ongoing research, innovative technologies, and multidisciplinary collaboration will further refine medication review processes, ultimately improving the quality of care for this vulnerable population.