Polypharmacy is defined as receiving multiple medications and has been shown to increase the risk for developing dementia. Polypharmacy is also prevalent in people with dementia (PwD) who transition to a care home. This study explored whether people receiving multiple medications are more likely to be diagnosed with dementia. Another aim was to assess the prevalence of polypharmacy (≥4 drugs) and hyperpolypharmacy (≥10 drugs) in community-dwelling PwD and care home residents in Northern Ireland, as well as to investigate whether higher polypharmacy scores are associated with increased likelihood of transitioning to a care home for PwD. Data from the Enhanced Prescribing Database and other national databases was linked through the Honest Broker Service. Data extraction included over 50,000 people, half of which were prescribed at least one anti-dementia medication between 2010-2016. The results showed that, although polypharmacy was not associated with the risk of developing dementia, higher scores of polypharmacy were associated with lower risk of transitioning to a care home for PwD. A possible explanation could be the increased mortality rates in people who received four or more medications. Within care homes, polypharmacy was more prevalent to PwD compared to controls. These findings can inform policies and clinical practices for the effect of prescribing multiple medications to PwD.
