Introduction: Early-onset Parkinsonism is a condition that has received little attention from researchers due to its low incidence and prevalence. We conducted a retrospective, cross-sectional, multi-centre study in order to obtain a representative sample of the Spanish population.
Patients and methods: The study involved 92 Spanish patients who had been diagnosed with idiopathic Parkinson's disease that began before the age of 40 years and these patients were divided into two groups: group 1, which consisted of 86 patients, with an age at onset of between 21 and 40 years (early-onset Parkinsonism), and group 2, with an age at onset of below 21 years, which included a total of 6 patients (juvenile Parkinsonism). Our analysis involved demographic data, patient's personal and family history, age and symptoms of onset of the disease, complementary studies, drug therapy and pharmacological complications.
Results: In group 1 we found a high incidence of early-onset Parkinsonism in the family. In our series there was a clear predominance of patients from urban settings. The predominant form of onset was akinesia, followed by tremor at rest, rigidity and postural tremor. Since they began treatment with levodopa, some patients presented fluctuations and dyskinesias which progressively increased over the years.
Conclusions: Our series of patients is not wholly similar to those reported in the literature; it is comparable, however, to those found in western countries and can be considered to be valid due to the number of cases analysed and owing to the fact that patients were selected from different areas around Spain. This provides an overall picture of this subtype of Parkinson's disease for the country as a whole.