Parkinsonism in a population-based study of individuals aged 75+ years: The Pietà study

Introduction: Parkinsonism is one of the most prevalent neurological syndromes in the elderly. There are only a few epidemiological studies focusing on parkinsonism in oldest-old individuals, particularly in Latin America. This study aims to investigate the prevalence and characteristics of parkinsonism in subjects aged 75 + years living in the community. Methods: The Pietà study is a population-based investigation on brain aging conducted in Caeté, southeast Brazil. A sample composed of 610 community-dwelling individuals aged 75 + years (48.7% of the total population within this age range) underwent clinical, neurological, cognitive and functional assessments. Results: The sample comprised mostly women (61.5%), with mean age of 83.3 years and mean schooling of 2.5 years. Parkinsonism was identified in 65 subjects (crude prevalence = 10.7%). Parkinson's disease, Parkinsonism + dementia syndrome, drug-induced parkinsonism, vascular parkinsonism and Lewy-body dementia were identified in, respectively, 19 (29.2%), 19 (29.2%), 8 (12.3%), 4 (6.1%) and 1 (1.5%) subjects. In 14 individuals (21.5%), the etiology of parkinsonism could not be determined. The most important vascular risk factor was hypertension (64.6%). Cognitive evaluation disclosed dementia in 37 (56.9%) subjects. Mean Pfeffer's functional activities questionnaire score was 12.2 points and 22 (33.8%) subjects were impaired in basic activities of daily living. Conclusion: Parkinsonism was common in this oldest-old population, being associated with dementia and vascular risk factors, particularly hypertension. Different confounders, such as concomitant dementia and exposure to anti-dopaminergic drugs, were present in this population, challenging the definition of causes of parkinsonism.