The effect of depression on motor function and disease severity of Parkinson's disease

Approximately 40% of patients with Parkinson's disease (PD) experience symptoms of depression. Our aim was to evaluate the effect of depression on disease severity, motor function and other phenotypic characteristics of PD.

We studied 32 PD patients with major depression (PD-D) according to the DSM-IV criteria and 32 PD patients with no depression (PD-C) matched for gender, age of onset and duration.

Major depression in PD patients was associated with increased disease severity, poorer motor function and worse performance in the activities of daily living as measured by UPDRS scores. Furthermore, there was an association of depression with the severity of bradykinesia and axial rigidity.

Depression in PD can have a profound negative impact on a patient's sense of wellbeing and motor functioning. Therefore, PD patients should be routinely and carefully screened for the presence of depression and appropriate management should be considered. Larger studies on the subject are warranted.