Depression is associated with impairment of ADL, not motor function in Parkinson disease

We read the Holroyd et al. article with great interest.1 We evaluated 50 patients with Parkinson disease (PD). All patients had idiopathic PD, none had a previous history of stroke, and all met Diagnostic and Statistical Manual of Mental Disorders–III criteria for dementia. We evaluated depressive state using Zung self- rating depression scale.2 Motor disability (tremor, rigidity, bradykinesia), Hoehn & Yahr stage, age at onset, levodopa dosage, duration of illness, history of depression, and score on Mini-Mental State Examination3 did not correlate with the SDS …