Researchers funded by Health Data Research UK (HDR UK) have developed a new tool to help doctors and pharmacists identify older patients at risk of delirium and serious falls associated with taking multiple anticholinergic medications.
Anticholinergic medications are widely used to treat a range of conditions. However, there are many medications that have anticholinergic effects even when this is not their main purpose. Taking multiple medications with these effects, known as anticholinergic burden, can increase the risk of delirium, falls and dementia – particularly in older people.
Published in BMJ Medicine , researchers at the University of Leeds, University of Liverpool and Bradford Institute for Health Research have developed the Anticholinergic Medication Index (ACMI) to score a patient's anticholinergic burden, based on the risk of delirium or falls. Researchers designed the ACMI to be embedded into electronic patient record systems, enabling healthcare professionals to efficiently prioritise patients with a high score to optimise their medicines.
First author Dr Kate Best, Associate Professor of Applied Statistics at the University of Leeds, said:
"Approximately 50% of older adults are prescribed at least one anticholinergic medication annually in the UK. While an anticholinergic medication might sometimes be the best treatment, with so many drugs that have this unintended side effect, anticholinergic burden can easily accumulate and pose a significant risk.
"Falls and delirium can be devastating for the health and wellbeing of older people, with considerable cost to the NHS. For patients with multiple health conditions, it may be reassuring to know there is a tool that can flag when they might need a medication review and support them to live well for longer."
The research team piloted the ACMI at GP surgeries in Bradford to automatically generate a list of patients aged 65+ with their ACMI score, the anticholinergic medicines contributing to the score and their one year predicted risk of fall or delirium. Without the tool, this information would have needed to be worked out patient by patient before pharmacists could use it to prioritise those most at need for a structured medication review.
Professor Andy Clegg, Head of the Academic Unit for Ageing and Stroke Research and Co-Director of HDR UK North and NIHR ARC Yorkshire and Humber said:
"Anticholinergic burden is a significant concern for older people, contributing to major health problems including delirium, falls, and dementia, alongside other side effects such as constipation, problems emptying the bladder, and dry mouth. As a consultant geriatrician, I frequently see patients on multiple anticholinergic medications that may be contributing to delirium and falls.
"We have designed the ACMI to integrate with electronic patient record systems and have successfully deployed the tool to support safer prescribing in primary and secondary care. Our ACMI has been designed to be built into EPR systems, rather than using a separate online system, providing a highly efficient automated calculation for busy clinicians to make the best decisions for their patients."
Dr Aseel Abuzour, Senior Research Fellow at the University of Leeds, and Professor Clegg also lead on a study embedding ACMI directly into hospital electronic patient record systems at two NHS Trusts, with support from the National Institute for Health Research (NIHR). The calculator, known as Anticholinergic Medication Index Clinical Decision Support System (ACMICS), is now live in two Trusts and in use.
Dr Abuzour said:
"Very few clinical prediction models are ever implemented in clinical practice. ACMICS is one of the few that has been. It is embedded directly within the EPR, appearing at several points across the system according to clinical workflow, and automatically recalculates whenever an anticholinergic is prescribed or stopped. Its design was informed by observations of clinical practice rather than assumptions about where the score would be most useful. We have also produced a technical specification so other organisations can develop an equivalent solution within their own EPR."
The ACMI was developed and tested using health data from nearly 750,000 adults aged over 65 years, making it one of the largest studies of its kind. To develop the index, researchers accessed de-identified routinely collected healthcare data through Connected West Yorkshire, an anonymised linked dataset containing primary and secondary care records. It was then tested using a large national dataset of patients in Wales held within the Secure Anonymised Information Linkage (SAIL) Databank.
Professor Sir Munir Pirmohamed, Co-Director of HDR UK North and David Weatherall Chair in Medicine at the University of Liverpool, said:
"We have known about the risks associated with anticholinergic medicines for many years. The challenge has been turning that knowledge into practical action that can reduce the risks for patients. The ACMI provides a real opportunity to make that happen, and it is one we should grasp."
The team are currently piloting the ACMI tool in several geriatric medicine and orthopaedic hip fracture hospital wards to examine the feasibility of wider roll-out in secondary care.
