Clinical features and medical treatment of Parkinson's disease in patient groups selected in accordance with age at onset.

In a recent hospital-based study on patients with different age at onset of PD, some clinical and therapeutic features were investigated. In the retrospective analysis three groups were selected: age at onset between 20 and 39 years (young onset), between 40 and 59 years, and from 60 years and up. The evaluation of our data demonstrates some significant differences in the above-mentioned groups: prevalence of male patients and more frequent occurrence of motor fluctuations and dyskinesias in the young onset group, longer duration of PD and L-DOPA treatment, higher L-DOPA dosage, and more multiple combinations in this group. We also noted more habitual smokers in the young onset group. Sex-specific differences in the young onset group were also investigated. A longer duration of disease was found in women, and some symptoms, such as pulsion and freezing and biphasic dyskinesia, are more frequent in women.