Pharmacist interventions may not improve polypharmacy, study shows

There is no clear evidence that pharmaceutical care-based interventions improve appropriate polypharmacy in older people, results of a recent Cochrane review show.

The review included 32 trials involving a total of 28,672 people aged 65 years and over. One intervention involved computerised decision support (CDS) while the remaining 31 were complex pharmaceutical care-based approaches, such as outreach by pharmacists, screening of automated drug alerts by consultant pharmacists, and clinical pharmacist interventions. The types of approaches studied included those targeted just at drug prescribing but most were multi-faceted.

The researchers, from Queen’s University Belfast School of Pharmacy, found it was unclear whether pharmaceutical care improves medication appropriateness. There was also no impact on the number of potentially inappropriate prescriptions or proportion of patients with potentially inappropriate prescriptions.

There was some evidence that the interventions may slightly reduce the number of potential prescribing omissions, but not the proportion of patients with a potential prescribing omission. Additionally, the team concluded there was little or no impact of pharmaceutical care on hospital admissions, quality of life or medicine-related problems. Though there was no consistent effect of intervention on medicines-related problems, the authors noted that CDS may be a helpful component for improving appropriate polypharmacy.

The review, published on 3 September 2018, is an update to three previously published versions, published in 2009, 2012, and 2014, and included 20 new studies. However, the researchers note that the overall quality of the research was low and the two studies reporting a benefit on potential prescribing omissions had a high risk of bias. They say that many questions still remain over effective strategies to improve appropriate polypharmacy, including the frequency and duration of the intervention, which elements of the intervention are most critical for success and whether interventions should be multi or uni-faceted.

The researchers looked at the appropriateness of prescribing rather than the number of medicines prescribed to patients, which they explain is a trend in the field, reflecting a drive to select combinations of medicines that optimise clinical outcomes, rather than minimising the number of medications.

“Differentiating between ‘many’ medicines (appropriate polypharmacy) and ‘too many’ medicines (inappropriate polypharmacy) is a prescriber’s dilemma, and choosing the best interventions aimed at ensuring appropriate polypharmacy remains a challenge for healthcare practitioners and organisations,” they write in the paper.