Medicines are the commonest treatment used by doctors to improve health. However, we have an ageing population with increasingly complicated medical needs, leading to multiple medicines being prescribed for a single patient. This is called polypharmacy. Although polypharmacy can often help improve a patients health, it can also be inappropriate, causing problems such as side effects and reduced quality of life. There is currently no useful way to measure whether or not polypharmacy is inappropriate. We propose to develop a method, which will help health services identify patients receiving inappropriate polypharmacy, and improve patients medicines.
We have previously developed a list of aspects of prescribing considered by clinical experts to be relevant to inappropriate polypharmacy. We will develop a version of this list which can be used to measure inappropriate polypharmacy in computerised health records such as CPRD. We will find out how well this computerised measure matches the expert opinion of doctors and pharmacists for 600 patient records. We will then use the measure to find out the extent of inappropriate polypharmacy in 300,000 CPRD patients, including what factors are associated with it (e.g. age, certain diseases) and whether the measure can identify harms (e.g. medication errors, side effects).
Medicines are a major therapeutic intervention available to clinicians. We have an ageing, increasingly multimorbid population, driving the phenomenon of polypharmacy (multiple drug use in an individual). Although sometimes clinically justified, polypharmacy can also be inappropriate, leading to undesirable outcomes (e.g. prescribing errors, impaired quality of life, adverse effects). There is no accepted means of quantifying inappropriate polypharmacy. The aim of this project is to develop a valid, reliable measure of inappropriate polypharmacy for use in clinical practice.
We have previously conducted an expert consensus process to identify key aspects of prescribing considered relevant to inappropriate polypharmacy, focusing on generic aspects of prescribing. We will operationalise those aspects that are readily quantified using routine health data, to develop an Inappropriate Polypharmacy Score (IPS). The concurrent validity of the IPS will be established by comparing it against expert ratings of 600 polypharmacy cases randomly drawn from CPRD representing a range of polypharmacy. An epidemiological analysis will then be conducted in 300,000 patients to examine the clinical and sociodemographic factors associated with the IPS, association between IPS and relevant adverse outcomes including adverse reactions, errors and health service use (predictive validity), and practice-level reliability.
Inappropriate polypharmacy
Primary care consultation rate
Adverse drug reaction
Death
Rupert Payne - Chief Investigator - University of Bristol
Rupert Payne - Corresponding Applicant - University of Bristol
Peter Tammes - Collaborator - University of Bristol
Richard Morris - Collaborator - University of Bristol
HES Admitted Patient Care;ONS Death Registration Data;Patient Level Index of Multiple Deprivation