Developing a measure of appropriate polypharmacy in primary care: the first steps

Written by Jenni Burt, University of Cambridge

Increasing multimorbidity and the rising numbers of guidelines focussing on how to treat specific medical conditions have led to widespread polypharmacy (the use of multiple medications in one individual). Of course, in many cases polypharmacy may be entirely clinically appropriate; but not in every case. There is increasing evidence on the association of polypharmacy with a range of undesired outcomes, including reduced quality of life, medication errors, and adverse drug reactions. In research, we have typically defined polypharmacy using simple counts of medication; for example, if someone is taking five or more medications, they may be marked as a person experiencing polypharmacy. However, these approaches do not take account of whether someone taking ten medications is doing so quite rightly, as they work well together; or whether such a regimen is of concern, and causing a whole host of unforeseen problems.

In this programme of research, we are aiming to develop a means of measuring polypharmacy which takes account both of the numbers of medications someone has been prescribed, and of whether these medications are clinically appropriate. We would also like this measure to apply to all patients (not just those with particular diseases, for example), so that general practices are able to readily identify those patients who would benefit from a more in-depth discussion about what is and isn’t working for them. 

As the first step in this programme, we have recently completed an extensive review of the literature to identify existing approaches to defining and measuring appropriate polypharmacy. We then took these ideas to a panel of clinical experts (GPs, pharmacists, geriatricians and pharmacologists) to see which of these they agreed were key elements of a measure of appropriate prescribing, in the context of polypharmacy. This was a two-stage process. First, panel members completed an online survey in which they reviewed 160 possible measures (covering different aspects of prescribing) to tell us which of these they considered to be the most important. After this, they met face-to-face for a full day of discussions, to review and further consider these measures.  At the end of this, the panel identified 134 different statements (many of them overlapping) from the literature, from which to pull together an initial measure of polypharmacy. Through further discussions with the research team and panel, we then whittled this down to the 12 most important areas to assess in measuring polypharmacy. These cover issues such as whether a patient is taking their medication or not (adherence); whether they have had an unexpected reaction (adverse effects); and whether medications may be interacting with each other or with conditions and causing undesirable symptoms or problems (interactions and contraindications). The full list will be presented  for the first time at the Society for Academic Primary Care conference in Warwick.

Now we have a clear idea of the important areas of appropriate polypharmacy, we are moving on to look at how we can use this within GP clinical systems. This is a key stage in the project, as we make progress towards our goal of identifying which patients may be experiencing inappropriate polypharmacy.

 (Image: Dr Jon Ferdinand, Primary Care Unit)