[Epidemiology of Parkinson's disease in Spain and its contextualisation in the world].

INTRODUCTION: The study of the epidemiology of Parkinson's disease (PD) is essential because it is a public health problem and because the differences in its prevalence and incidence offer clues as to the existence of aetiologically important environmental or biological factors.

AIMS: To report the most relevant data about the descriptive epidemiology (prevalence, incidence and mortality) of PD from studies conducted in different countries, with special emphasis on those carried out in Spain and Latin America. Likewise, the study also includes a discussion of some of the main risk factors or protectors of this disease (analytical epidemiology) that have emerged thanks to the data obtained from large cohorts in the literature.

DEVELOPMENT: We conduct an analysis of the most significant population-based studies, focusing especially on those conducted using the 'door-to-door' methodology.

CONCLUSIONS: Its prevalence and incidence vary greatly around the world. In general, prevalence is higher in Europe and the United States than in other countries and is relatively uniform, fluctuating over a range that is not very noteworthy. In Asian, Latin American and African countries it is lower, especially in this last continent. These differences could be partly due to the specific factors of the population studied (that is to say, higher mortality rate due to lower economic resources). The most firmly established risk factors are ageing and being male.