Use of Potentially Harmful Medications and Health-Related Quality of Life among People with Dementia Living in Residential Aged Care Facilities

BACKGROUND: Use of potentially harmful medications (PHMs) is common in people with dementia living in Residential Aged Care Facilities (RACFs) and increases the risk of adverse health outcomes. Debate persists as to how PHM use and its association with quality of life should be measured. We designed this study to determine the association of exposure to PHM, operationalized by three different measures, with self-reported Health-Related Quality of Life among people with dementia residing in RACFs. METHODS: Cross-sectional study of 351 people aged >65 years diagnosed with dementia residing in RACFs and with MMSE ≤24. The primary outcome measure was the self-rated Quality of Life – Alzheimer's disease questionnaire (QoL-AD). We collected data on patients’ medications, age, gender, MMSE total score, Neuropsychiatric Inventory total score, and comorbidities. Using regression analyses, we calculated crude and adjusted mean differences between groups exposed and not exposed to PHM according to potentially inappropriate medications (PIMs; identified by Modified Beers criteria), Drug Burden Index (DBI) >0 and polypharmacy (i.e. ≥5 medications). RESULTS: Of 226 participants able to rate their QoL-AD, 56.41% were exposed to at least one PIM, 82.05% to medication contributing to DBI >0, and 91.74% to polypharmacy. Exposure to PIMs was not associated with self-reported QoL-AD ratings, while exposure to DBI >0 and polypharmacy were (also after adjustment); exposure to DBI >0 tripled the odds of lower QoL-AD ratings. CONCLUSION: Exposure to PHM, as identified by DBI >0 and by polypharmacy (i.e. ≥5 medications), but not by PIMs (Modified Beers criteria), is inversely associated with self-reported health-related quality of life for people with dementia living in RACFs.