[Clinical and epidemiologic characteristics of familial Parkinson disease].

We have studied 44 patients diagnosed of idiopathic Parkinson disease included in our database of rigid-akinetic syndromes. We have compared their demographic, environmental and clinical features with the ones that presented a group on 22 patients diagnosed of idiopathic Parkinson disease and had some first degree relatives with the same disease. Patients with familial Parkinson disease are distinguished from the ones that suffer from sporadic Parkinson disease because of an early start, greater consanguinity rate and greater frequency of a similar disease in their parents. Moreover, we have seen that familial Parkinson disease patients have drunk more water from wells during their lives than the ones that suffer sporadic Parkinson disease, present greater frequency of wide motoricity disorders, dystonia, night hypokinesia, fluctuations in relation to L-DOPA and greater frequency of early going grey. We have not found either epidemiologic data which could explain the appearance of familial cases or environmental causes which could produce familial Parkinson disease. Clinical differences between the two groups are likely due to an early start of symptoms in familial Parkinson disease cases. According to our data we could not conclude that between familial and sporadic Parkinson disease are significant differences in to justify two well-defined diseases. Even, the familial presentation of idiopathic Parkinson disease could be the normal form of Parkinson disease if long survival was a favourable factor of disease onset in pre-symptomatic persons.