Epidemiology of atypical parkinsonian syndromes

Abstract Atypical parkinsonism or atypical parkinsonian syndromes (APS) refer to a group of neurodegenerative disorders which mimic typical Parkinson’s disease but poorly respond to levodopa treatment and deteriorate faster. APS are very rare and among them, progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and corticobasal degeneration (CBD) are the three relatively better characterized entities. The prevalence estimates of PSP, MSA, or CBD are mostly <10/105, and the incidence estimates are around 1/105 person-year; both estimates remain stable over the