A dementia diagnosis is more likely in people who are taking three or more medications, according to an international research team.
The study is the first to explore the links between the number of pharmaceuticals taken by an individual and dementia diagnosis. The study was based on an analysis of 33,000 dementia patients in Wales between 1990 and 2015.
The research team applied machine-learning techniques to identify damaging patterns in patients’ medicine usage. The researchers wanted to understand how these patterns evolve prior to dementia diagnosis.
The study analysed results from Health Data Research UK and was 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.
The findings have been published in the Aging and Disease journal.
Medication use rises significantly in the years prior to a dementia diagnosis
The researchers found that the proportion of patients using three or more pharmaceuticals in the 20 years leading to their dementia diagnosis, rose from 5.5% to 82.16% among those less than five years away from a diagnosis.
The researchers also observed that as developments towards dementia grew in patients, the patterns of polypharmacy (the use of multiple medications) shifted from broader use drugs to more specific pharmaceuticals.
The findings revealed that those closest to their dementia diagnosis were taking multiple medicines for a combination of respiratory conditions, urinary infections, arthropathies and rheumatism, and cardiovascular disease. This pattern was found in 66.55% of participants. A further 22% of participants were taking one form of medication for the same conditions.
Prescription needs to be safer for patients
“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,” said Shangming Zhou, Professor of e-Health at the University of Plymouth and lead author of the study.
“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.”
Previous research has established using multiple types of preventative medication for various conditions can reduce the efficacy of the treatments. The chances of side effects and harm are also increased with drug interaction. As well as this, patients taking multiple medications are also known to have a higher risk of re-admission within three months of being discharged.
As the number of people with dementia in the UK is set to rise to 1.6 million by 2040, the researchers hope their findings will inform safer prescribing practices. They also encourage doctors to consider cognitive impairment when administering drugs to patients.
