Study explores links between people taking multiple medications and dementia diagnosis

An in-depth investigation has been conducted on the links between growing polypharmacy, which entails a patient being prescribed more than one medicine at any same time, and dementia diagnosis.

The study is the first to look in depth at the relationship between growing polypharmacy (when a patient is prescribed more than one medicine at the same time) and dementia. It was published in the journal Aging and Disease and is based on a review of more than 33,000 dementia patients’ data in Wales from 1990 to 2015.

Experts in e-health used machine learning techniques to identify potentially damaging patterns in a patient’s medicine usage, and how these patterns evolve in the run-up to diagnosis.

They found that in the 20 years leading up to them being diagnosed, the proportion of patients taking three or more medications rose from 5.5% (for the period 16 to 20 years prior to diagnosis) to 82.16% among those less than five years from a diagnosis.

Researchers also found that as the development towards dementia progressed, the patterns of polypharmacy shifted from being clearly distinct to being more closely associated with particular medical conditions.

And of those closest to their diagnosis, almost two-thirds (66.55%) were found to be taking multiple medicines for a combination of respiratory or urinary infections, arthropathies and rheumatism, and cardiovascular disease. A further 22% of patients were found to be taking medicines for infections, arthropathies and rheumatism, cardio-metabolic disease and depression.

The study was supported by the Health Data Research UK and conducted by an international team of researchers from the University of Plymouth, Aptuit (an Evotec company), Swansea University Medical School, and the University of Oxford.
Shangming Zhou, Professor of e-Health at the University of Plymouth, led the study.

He said: “Given the rise in dementia cases internationally, the need to understand how patterns of polypharmacy evolve before and after a dementia diagnosis are important for devising a safe treatment programme for each patient. Our aim in this study was to help doctors find ways to prescribe multiple items of dementia medication safely and without reducing their effectiveness. The use of machine learning has been vital in helping us understand how these patterns develop, and our hope is we can now use this knowledge to treat patients.”

It has previously been established that when multiple types of preventative medication are being prescribed, the benefits of the drugs may be reduced and the chances of harm from drug interaction and side effects increased.

Those who require hospitalisation and are taking many drugs are also more likely to be readmitted within three months of release.

With the number of dementia patients in the UK expected to reach 1.6 million by 2040, researchers believe that this new study will influence safe prescription practises and urge clinicians to prescribe medication combinations designed to reduce cognitive deficits.

Also Read: Study reveals how serotonin helps to improve mental health