Polypharmacy and frequently used medications before death in Qc: any differences between persons with and without dementia?

Context: Few studies have looked at polypharmacy and frequently used medications in the last months of life of persons with dementia (PWD), where the benefits of some medications are uncertain. We still do not know to which extent the medication differs between PWD and persons without dementia (PWOD) near the end of life.

Objective: To describe the prevalence of polypharmacy and frequently used medications in the 90 days before death in PWD and PWOD.

Study Design: Repeated yearly cohort study from 2007 to 2022.

Dataset: Provincial database linking 5 Quebec health administrative databases.

Population Studied: Community-dwelling decedents aged 65 years and 90 days and older at the date of death, with and without dementia.

Outcome Measures: Prevalence of polypharmacy and frequently used medications are measured in the 90 days before death. Polypharmacy is defined as taking 5+, 10+, 15+ and 20+ different medications on the 90 days period and is identified using the common drug denomination classification system. We measured on the last cohort the 25 most frequent medications. We performed descriptive analysis with direct age standardization.

Results: In the 15 cohorts, 101 142 PWD and 417 418 PWOD were included; mean age 86,5 and 80,1; female 59,2% and 47,1% respectively for PWD and POWD. Average age-standardized number of medications was similar in both group and rose through the years, ranging from 10,8 in 2007 to 12,6 in 2021. Polypharmacy (5+, 10+, 15+, 20+) was similar in both group for the 15 years. PWD had more psychoactive medication than PWOD (3/25 vs 0/25) and PWD had less palliative care medication (4/25 vs 7/25).

Conclusion: PWD and PWOD are affected by polypharmacy, even in the 90 days before death. This problem tends to increase through the years despite the growing literature on negative impact of polypharmacy, especially in PWD. Our study shows that there are important differences in categories of medication. PWD have more psychoactive medication and have less palliative care medication that PWOD, suggesting less access to palliative care. Our results will be used to raise awareness among clinicians, managers, and decision-makers on the extent of polypharmacy at the end of life among all older persons in Quebec and the suspected gap in palliative care access for PWD.