Introduction: Depression is a state of mind often associated with Parkinson's disease, which is not correlated with the stage of the disease or the response to treatment with L-dopa. It has been suggested that patients with right-sided Parkinsonism have more depression than those with left-sided.
Objective: To assess whether patients whose dominant side is affected primarily have more depression than those whose non-dominant side is affected; and to evaluate whether when the dominant side is more affected this is accompanied by greater deterioration on the scale of everyday activities (ADLS) and on the motor part of the unified scale for evaluation of Parkinsonism (UPDRSm).
Patients and methods: The study group was formed of 63 patients with Parkinsonism at stage 1 or 1.5 (Hoehn and Yahr), with an average age of 66.17 years. They were divided into two groups. Those who received L-dopa (Dopa group) and those who were newly-diagnosed patients (Naive group). They were evaluated on the Hamilton test, UPDRSm and ADLs scale. We used Wilcoxon's nonparametric sum of ranges test taking p < 0.01 as significant.
Results: The indexes of depression were greater, in both groups, in the patients whose dominant side was affected (p < 0.001). There were no differences in UPDRSm or ADLs.
Conclusions: The patients with Parkinson's disease whose dominant side is primarily affected have worse depression. The depression seems originate in the dominant hemisphere.