Abstract
Of 261 patients with clinically diagnosed Parkinson's disease (PD), whose age at the onset was 58.2 ± 11.3, 46 patients with the onset age above 70 (the mean for the whole group + ISD) were compared to 44 patients with onset age below 47 (the mean for the whole group – ISD). Old‐onset PD patient were more susceptible to develop psychotic complications of levodopa treatment. More often had they tremor both as presenting and dominant symptom of their disease. Among young‐onset PD bradykinesia was more often the dominant clinical feature, and susceptibility to levodopa induced dyskinesia was higher. In 9 cases of young‐onset PD (20.5% of this group) paraesthesia was a presenting symptom, compared to only 1 patient (2%) in the group of old‐onset PD.