Improving Medicines use in People with Polypharmacy in Primary Care (IMPPP): Clinical effectiveness of a complex intervention to improve prescribing appropriateness in patients with polypharmacy

Conference:

SAPC ASM 2024 - Bristol

Talk Code:

1B.3

Presenter:

Rupert Payne

Co-authors:

Peter S. Blair, Barbara Caddick, Carolyn A. Chew-Graham, Tobias Dreischulte, Lorna J. Duncan, Bruce Guthrie, Cindy Mann, Roxanne M. Parslow, Jeff Round, Chris Salisbury, Katrina M. Turner, Nicholas L. Turner, Deborah McCahon

Author institutions:

University of Exeter, University of Bristol, Keele University, Ludwig-Maximilians-University (Munich), University of Edinburgh, Institute of Health Economics (Alberta, CA)

Problem

Polypharmacy is common and associated with undesirable consequences. Clinical management of polypharmacy is challenging in primary care because it requires balancing therapeutic benefits and risks, and clinical and patient priorities. It also requires overcoming important barriers to effective medication optimisation, such as suboptimal case-finding, inadequate clinical training, poor informatics solutions, and a failure to incentivise good care. Current strategies for managing polypharmacy are varied, and not supported by high quality evidence. The aim of the Improving Medicines use in People with Polypharmacy in Primary Care (IMPPP) trial was to evaluate the effectiveness of a complex intervention to optimise medication use for patients with polypharmacy in a general practice setting.

Approach

The IMPPP trial was a multicentre, open-label, cluster-randomised trial, with two parallel groups. 37 practices (19 intervention) were recruited from the South-West and West Midlands. Practices were randomised either to usual care, or to a complex intervention comprising a clinical informatics tool (designed to support medication review), case-finding, pharmacist and general practitioner (GP) training (focused on patient-centred care and medication review) and a four-stage structured medication review (pharmacist-led case-note review, inter-professional collaborative discussion between pharmacist and GP, patient-facing review, and follow-up if considered clinically indicated). Up to 50 patients receiving multiple (5+) regular medications and triggering at least one potentially inappropriate prescribing (PIP) indicator were recruited per practice. The primary outcome was number of PIP indicators, captured objectively through GP electronic health records (EHRs). Secondary outcomes included medication burden and adherence, patient experience, and health service use, measured through EHRs and patient self-report. The main intention-to-treat analysis was linear mixed effects regression, comparing the number of PIP indicators triggered at 26-weeks post-review between groups, adjusted for baseline (pre-randomisation) values.

Findings

Study population was 1727 patients, median age 73 years (IRQ 66-79), with 51% male. Medication reviews were conducted between 4 Oct 2022 and 3 Oct 2023. Analysis is ongoing at present. Results of the primary outcome and other key secondary outcomes will be reported at the SAPC 2024 Annual Scientific Meeting.

Consequences

IMPPP is one of the largest clinical trials of a complex intervention for polypharmacy. The intervention is readily scalable and aligns with current health service systems and processes. The results will establish the clinical effectiveness of the IMPPP intervention with the potential to inform change in the delivery of existing medication optimisation services, and consequent improvements in prescribing in a substantial proportion of patients.

Submitted by:

Rupert Payne

Funding acknowledgement:

This project was funded by the National Institute for Health Research (NIHR) under its Health and Social Care Delivery Research programme (Grant Reference Number 16/118/14). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.