Update: Descriptive epidemiology of Parkinson disease

We review the descriptive epidemiology of Parkinson disease (PD). PD is a prevalent neurologic disorder in high Socio-Demographic Index (SDI) nations with rising prevalence in low and middle SDI nations. PD became a prevalent disorder in high SDI nations during the 20th century. Population growth, population aging, and increased disease duration are major drivers of rising PD prevalence. Exposure to industrial toxicants may also be a contributor to rising PD prevalence. PD is an age-related disorder with incidence likely peaking in the 8th decade of life and prevalence in the 9th decade of life. PD is notable for significant sex difference in PD risk with greater risk in men. There may be ancestral differences in PD prevalence and risk. PD is associated with moderately increased mortality though this may be underestimated. Despite significant research, there is considerable uncertainty about basic features of PD epidemiology.