Prevalence and determinants of polypharmacy and its association with cognitive and functional performance in community-dwelling older adults: A population-based study.

BackgroundPopulation aging is accompanied by increasing multimorbidity and medication exposure, raising concerns regarding the role of polypharmacy as a potential modifiable risk factor for cognitive decline and Alzheimer's disease. However, polypharmacy is a heterogeneous construct, and its cognitive impact may depend more on regimen complexity and pharmacological burden than on medication count alone.ObjectiveTo estimate the prevalence and determinants of polypharmacy and to examine its association with functional status and cognitive performance in community-dwelling older adults from southern Chile.MethodsA cross-sectional study was conducted between 2023 and 2025 including 848 adults aged ≥60 years from four provinces in the Los Lagos Region. Sociodemographic, clinical, and psychosocial data were collected through structured interviews and standardized assessments. Functional status was evaluated using EFAM-Chile, Barthel, and Pfeffer scales, and Cognitive performance and functional status were assessed using the Preventive Medicine Examination for Older Adults (EFAM-Chile). Polypharmacy was defined as the concurrent use of ≥5 medications, including prescribed and over-the-counter drugs. Regimen complexity and anticholinergic/sedative burden were quantified using the Medication Regimen Complexity Index (MRCI) and the Drug Burden Index (DBI).ResultsPolypharmacy was associated with better functional and cognitive scores in unadjusted analyses (p < 0.05), although these associations were not independent after adjustment. Multimorbidity was the strongest predictor of medication count. Despite greater medication exposure, MRCI and DBI values remained within low-to-moderate ranges, indicating limited pharmacological burden relevant to cognitive vulnerability. These findings may be explained by reverse causation or by confounding related to health statusConclusionsIn this population, polypharmacy was not associated with cognitive screening outcomes, although the absence of detailed neuropsychological assessment limits conclusions regarding cognitive impairment or dementia risk and may reflect optimized management of chronic conditions. Qualitative pharmacological indices may improve the identification of medication-related cognitive risk in aging populations.