Patterns and Determinants of Dementia Pharmacotherapy in a Population-Based Cohort of Home Care Clients

Abstract

Little is known about the needs of older home care clients with dementia or their key quality of care issues, including their use of pharmacotherapy for Alzheimer's disease. The objectives of this study were to (1) describe the sociodemographic, psychosocial, and health characteristics of clients with dementia (relative to two control subgroups) from a population-based home care cohort; and, (2) determine the distribution and associated characteristics of cholinesterase inhibitor (ChEI) and/or memantine use among dementia clients overall and according to medication class, comorbid illness, and year of assessment. This cross-sectional study included all home care clients aged 50 years or older assessed with the Resident Assessment Instrument-Home Care (RAI-HC) in Ontario, Canada from January 2003 to December 2010. Multivariable logistic regression models were used to identify factors associated with receiving a dementia medication (a ChEI and/or memantine). There were 104,802 (21.5 %) clients with a diagnosis of dementia, 92,529 (18.9 %) cognitively impaired clients without a dementia diagnosis, and 290,929 (59.6 %) cognitively intact clients. Relative to the comparison groups, dementia clients were more likely to have reported conflicts with others, a distressed caregiver, greater levels of cognitive and functional impairment, and to exhibit wandering, aggressive behaviors, anxiety, hallucinations or delusions, and swallowing problems. Approximately half of dementia clients were taking a dementia medication, most commonly donepezil. Characteristics most strongly associated with use of ChEI monotherapy included age greater than 64 (especially 75-84), absence of economic barriers, availability of a primary caregiver, year of assessment, moderate to severe cognitive impairment, relative independence in function, health stability, no depressive symptoms or hallucinations/delusions, no recent hospitalization, use of at least 9 medications, the absence of chronic health and neurological conditions, and the use of an antipsychotic or antidepressant. For combination therapy, strong positive associations were observed for younger age, year of assessment, increasing cognitive impairment, presence of a primary caregiver, male sex, absence of economic barriers, use of at least 9 medications, and various indicators of positive health status (e.g., stability in health, absence of chronic health and neurological conditions, and no recent hospitalization). The percentage of clients receiving ChEIs increased with cognitive impairment scores but declined slightly at the highest level of impairment, whereas the percentage receiving memantine increased with cognitive impairment level. The number and percentage of dementia clients receiving any pharmacotherapy increased during the study interval. We observed a relatively high prevalence of dementia-specific pharmacotherapy among Ontario long-stay home care clients as well as significant variation in utilization patterns by select sociodemographic, functional, and clinical characteristics, and over time. While physicians generally followed recommended guidelines regarding appropriate dementia pharmacotherapy, continued efforts to monitor practice patterns are required among vulnerable older adults across care settings.