Improving medicines use in people with polypharmacy in primary care: a synopsis from the IMPPP cluster-RCT with...

Polypharmacy is a major challenge for patient safety and effective resource use. High-quality evidence supporting polypharmacy management is lacking.

To develop, optimise and evaluate a primary care complex intervention for reducing medically defined potentially inappropriate prescribing among patients experiencing polypharmacy.

Phase 1: Qualitative interviews and focus groups with patients and professionals explored views/experiences of existing National Health Service Scotland interventions, informing development of core intervention components. Phase 2: An external pilot-feasibility study was conducted in five general practitioner practices to optimise the Improving Medicines use in People with Polypharmacy in Primary care intervention. A formative mixed-methods process evaluation examined intervention implementation, alongside evaluating trial processes and collecting data to inform phase 3. Phase 3: A pragmatic, open-label two-arm parallel cluster-randomised trial was conducted in English general practice. The intervention (19 practices) comprised a structured, collaborative and patient-centred approach to medication review, supported by informatics, clinician training, performance feedback and financial incentivisation. The comparator was usual care (18 practices). Up to 50 adults receiving ≥ 5 regular medications, with ≥ 1 indicator of potentially inappropriate prescribing, were reviewed per practice over 6 months. Primary outcome was number of potentially inappropriate prescribing indicators at 26-week follow-up. Secondary outcomes included patient-reported measures and service use. Cost-effectiveness and cost-utility analyses were conducted (primary economic outcome quality-adjusted life-years). A mixed-methods process evaluation (patient surveys, patient/clinician interviews, audio-recorded observations) explored implementation.

Phase 1: Intervention component design was informed by findings related to elements of the medication review, informatics and clinician training. Phase 2: Core intervention elements were successfully implemented in the pilot, although clinical delivery was hampered by disruptions due to the coronavirus disease pandemic. Phase 3: Participants were recruited between January and June 2022 (intervention N = 891, usual care N = 836), median age 73 years, 49% female, with median four long-term conditions and eight medications. No improvement in the primary outcome was observed (mean difference potentially inappropriate prescribing count - 0.007; 95% confidence interval -0.21 to 0.199). Treatment burden was slightly improved, and subgroup analysis suggested potential improvements in less complex patients. The process evaluation found general practitioners and pharmacists valued and benefitted from the model of interprofessional collaboration, which strengthened working relationships and provided an opportunity for knowledge sharing and joint decision-making that supported management of clinical uncertainty. Most patients (73.2%) reported satisfaction with the review, with satisfaction strongly associated with perceptions of shared decision-making. There was no evidence of cost-effectiveness, although the economic evaluation did not quantify the aforementioned benefits or other broader factors of potential interest to decision-makers.

Key limitations include concurrent changes in usual care, potentially insensitive outcome measures and limited study-population generalisability.

A complex medication optimisation intervention did not reduce potentially inappropriate prescribing in patients with polypharmacy. Findings strongly support revisiting current medication optimisation policy, with one-off structured reviews, even when enhanced with digital healthcare solutions and clinical pharmacy investment, not guaranteed to improve key clinical outcomes. Nevertheless, the positive patient and clinician findings are important: protected time for interprofessional collaborative working, plus effective integration of shared decision-making within patient-facing reviews, may facilitate improved patient care more broadly.

Research should develop new patient-centred outcomes and identify higher-risk patients.

This synopsis presents independent research funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme as award number 16/118/14.