Does levodopa alter depression and psychopathology in Parkinsonism patients?

Twenty-seven Parkinsonism patients and 31 controls, matched for age and verbal IQ, were tested on an objectively scored personality test (Minnesota Multiphasic Personality Inventory) at the beginning of the patients' levodopa therapy and three months later. Patients, but not the controls, were retested after 15 months of levodopa treatment. The patients, all of whom were intact intellectually, obtained MMPI scores indicating moderate depression before beginning levodopa treatment. There was no test evidence to indicate that levodopa significantly increased or decreased the amount of depression in the patients after three or 15 months of levodopa. The patient group, however, significantly increased their Index of Psychopathology (Ip) score after 15 months of levodopa but not after three months.