Prescribing trends in older patients with multimorbidity and significant polypharmacy recruited to the SPPiRE trial

Conference:

SAPC ASM 2022 - UCLan

Talk Code:

3B.4

Presenter:

Caroline McCarthy

Co-authors:

Caroline McCarthy (1), Barbara Clyne (1), Susan M Smith (1, 2), Michelle Flood (3), Frank Moriarty (1, 3)

Author institutions:

1) HRB Centre for Primary Care Research, Department of General Practice, RCSI University of Medicine and Health Sciences, Dublin 2. 2) Department of Public Health and Primary Care, Trinity College, Dublin 2, 3) School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin 2

Problem

Identifying appropriate outcome measures to evaluate the effectiveness of medicines management multimorbidity interventions is challenging given the heterogeneity of the population. Supporting prescribing in older patients with multimorbidity (SPPiRE) was a cluster randomised controlled trial that demonstrated that a GP delivered individualised medication review led to a small but significant reduction in the number of medicines in older patients aged ≥65 years and prescribed ≥15 medicines (IRR 0.95, 95%CI; 0.899, 0.999, p=0.045) but no effect on potentially inappropriate prescriptions (PIP). The trial concluded that prescribing in this patient group is complex and that repeated assessments of prescribing related measures, may be more appropriate to allow analysis of the trends in prescribing in this vulnerable group. The aim of this study was to evaluate changes in prescribing in patients with significant polypharmacy (≥15 repeat medicines) during the SPPiRE trial, specifically looking at the commonly prescribed, commonly stopped and started, inappropriately prescribed and low clinical effectiveness medicines by ATC code.

Approach

We retrospectively analysed trial prescription data for 404 participants aged ≥65 years and prescribed ≥15 repeat medicines that were submitted at baseline and follow up by 51 recruited general practices. A dataset of 13,828 individual ATC coded medicines was generated and analysed using descriptive statistics.

Findings

There were 7,051 repeat medicines prescribed at baseline, of which 1,203 (17.0%) were PIP and 6,779 at follow-up of which 1,054 (15.5%) were PIP. The most commonly prescribed medicines by drug group at baseline were proton pump inhibitors (PPIs) (82% of participants), statins (77%), antiplatelets (61%), paracetamol, beta blockers and diuretics (all 48%). At follow-up, there was a reduction in the prescription of most drug groups, the largest reductions were in antiplatelets (5%), inhaled beta agonists (4%) and calcium channel blockers, non-steroidal anti-inflammatory drugs and diuretics (all 3%). The drug groups that were most frequently inappropriately prescribed were benzodiazepines and z drugs (98% of prescriptions were classified as PIP), medicines with anticholinergic potency (75%), PPIs (74%), NSAIDs (66%), diuretics (59%), and anti-psychotic medicines (38%). Overall 87 participants (22%) were prescribed at least one medicine classified as having a low clinical effectiveness reducing to 74 (18%) at follow up.

Consequences

At baseline, there was a high prevalence of PIP, including high risk medicines such as benzodiazepines and diuretics, indicating that these may be areas that warrant specific attention for patients with significant polypharmacy. Overall there was a reduction in prescribing of most drug groups during the study period indicating some degree of deprescribing, which may reflect an increasing focus on this area of medicines management.

Submitted by:

Caroline McCarthy

Funding acknowledgement:

This research in funded by the Health Research Board Primary Care Clinical Trial's Network, Ireland (CTN-2014-011).