The extent of medication complexity in general practice

Date of ISAC Approval: 
Lay Summary: 
Medicines are widely used to promote health and well-being. Most are prescribed in primary care. Proper use helps to prevent, treat or manage health conditions. Research shows that complicated instructions for taking medication effect how successfully that drug treats a condition. Medication complexity varies between patients, and is assessed by looking at how a drug is taken (e.g. a tablet or injection), how often it is taken, and whether extra directions are included, such as 'with food' or 'in the morning'. Patients with more complex drug routines may struggle to take their medication correctly. This is a problem because patients may take too-much or too-little of a drug, causing the medication not to work correctly. Our research will start with a random group of 300,000 patients from English general practices. We will use statistics to explore the range of medication complexity in this group. We will look at factors such as the patient's age, sex, socio-economic status and long-term health problems. We will then study the use of medication reviews and how they affect medication complexity. The results will help to identify patients that have more complicated medication routines, and how to improve the quality of care for patients taking prescriptions.
Technical Summary: 
Prescribing is a key therapeutic intervention offered by doctors, the majority occurring in primary care. With an ageing, multimorbid population, the number of patients taking multiple medication in the UK is increasing. Yet, patients' medication regimes differ depending on the drugs prescribed, and little is known about the epidemiology of medication complexity in the general population. A random sample of 300,000 patients aged 1 year or more will be selected and medication regimen complexity index (MRCI) score calculated for a random date in 2017. MRCI score will be compared across age, sex, socio-economic status and multimorbidity groups. In a second sample, 50,000 patients who had a medication review in 2017 will be matched to 50,000 patients who did not. A difference-in-difference analysis will be conducted using multivariable regression to compare changes in MRCI score before and after the medication review in exposed and unexposed patients. Adjustments will be made for age, gender, socioeconomic status, long-term morbidities, and GP surgery. This work will provide greater insight into the medication burden of the general UK population, and evaluate how successfully current medication reviews are in simplifying medication regimes. Understanding these issues will inform the development of interventions for improving medication optimisation.
Health Outcomes to be Measured: 
- medication Regime Complexity index

Dr Rachel Denholm - Chief Investigator - University of Bristol
Dr Rachel Denholm - Corresponding Applicant - University of Bristol
Dr Rupert Payne - Collaborator - University of Bristol
Thomas Greenslade - Collaborator - University of Bristol

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