Objectives The present study aimed to evaluate the impact of structured medication reviews (SMRs), by examining the proportion of eligible patients who received a review in the first two years of the programme, and whether SMRs were associated with changes in prescribing.

Design Retrospective observational cohort study.

Setting Patients registered to primary care practices in England contributing data to the Oxford Clinical Informatics Digital Hub (ORCHID) were included between 1st April 2020 and 30th September 2022.

Participants De-identified data were extracted from the electronic health records of individuals registered to ORCHID practices aged ≥65 years, prescribed one or more medications and fulfilling the specific eligibility criteria for a SMR.

Main outcome measures The primary outcome was the proportion of patients who received a review. Further outcomes included the proportion of potentially inappropriate drug combinations corrected following an SMR. The association between SMRs and prescription changes and primary care contacts was examined by matching individuals who received an SMR to individuals who did not receive an SMR, according to age, sex and primary care practice using cumulative density sampling. Analyses were undertaken using adjusted logistic regression.

Results From a total of 635,698 eligible patients, 82,285 patients (12.94%, 95% confidence interval [CI] 12.86% to 13.02%) received at least one SMR during the study observation period. In those prescribed potentially inappropriate drug combinations prior to an SMR, between 12.5% and 40.0% were corrected up to three months later. In matched analyses, SMRs were associated with a significant increase new prescriptions of ACE inhibitors (adjusted odds ratio [aOR] 1.56, 95%CI 1.35-1.81), statins (aOR 1.78, 95%CI 1.57-2.02), inhaled corticosteroids (aOR 1.19 95%CI 1.05-1.36), opioids (aOR 1.31 95%CI 1.20-1.42), and antidepressants (aOR 1.45 95%CI 1.28-1.63). In those previously prescribed treatment, individuals receiving an SMR were significantly more likely stop ACE inhibitors (aOR 1.37, 95%CI 1.18-1.58), statins (aOR 1.35, 95%CI 1.17-1.56) and antidepressants (antidepressants aOR 1.37 95%CI 1.21-1.56). SMRs were associated with a significant increase in primary care contacts of 0.14 (95% CI 0.13 to 0.16; equivalent to 14 extra patient contacts for every 100 individuals receiving an SMR).

Conclusions SMRs were associated with starting new medications and stopping existing prescriptions compared to usual care. It was unclear if such activity was appropriate or represented improved patient care. Further work is needed to understand if these changes in prescribing improved patient outcomes.

What is already known on this topic

Inappropriate polypharmacy can expose the most vulnerable patients to decreased quality of life and adverse drug events.

Outside of trials, studies of pharmacist-led medication reviews undertaken in routine clinical practice have shown little impact on prescribing and patient-centred care.

Structured medication reviews are a National Institute for Health and Care Excellence (NICE) approved clinical intervention to address complex or problematic polypharmacy and were introduced widely in the UK NHS in 2020.

What this study adds

We found that one in eight eligible patients received a structured medication review during the first two years of the programme’s rollout in England.

Structured medication reviews were associated with an increased likelihood of starting medication in those not previously prescribed treatment, and an increased likelihood of stopping medications in those with existing prescriptions.

This analysis was limited by the data available within primary care electronic health records and so it is unclear if the observed changes in prescribing resulted in improvements in patient outcomes

The authors have declared no competing interest.

This work was funded by the National Institute for Health Research (NIHR) Applied Research Collaboration Multiple Long-term Conditions Cross-ARC collaboration. JPS received funding from the Wellcome Trust/Royal Society via a Sir Henry Dale Fellowship (ref: 211182/Z/18/Z), and now receives funding via an NIHR Advanced Fellowship (NIHR303621). RB receives funding via an NIHR Advanced Fellowship (NIHR302557). FDRH, RM and KT were supported by NIHR Applied Research Collaboration Oxford and the Thames Valley (OxTV-ARC). RM is an NIHR Senior Investigator. KK and SS are supported by the NIHR Applied Research Collaboration East Midlands (ARC EM), NIHR Global Research Centre for Multiple Long Term Conditions, NIHR Cross NIHR Collaboration for Multiple Long Term Conditions, NIHR Leicester Biomedical Research Centre (BRC) and the British Heart Foundation (BHF) Centre of Excellence. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care. For the purpose of Open Access, the author has applied a CC BY public copyright licence to any Author Accepted Manuscript version arising from this submission.

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The study protocol was approved by South Central Hampshire A Research Ethics Committee (ref 22/SC/0373).

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