L-DOPA vs. Placebo for Depression and Psychomotor Slowing in Older Adults

Individuals with Late Life Depression (LLD) often have cognitive problems, particularly problems with memory, attention, and problem solving, all of which contribute to antidepressant non-response. Our group and others have shown that decreased thinking speed is the central cause of functional problems in patients with LLD. Similarly, decreased walking speed is associated with depression and carries additional risk for falls, hospitalization, and death. Available evidence suggests that declining functionality in the brain's dopamine system contributes to age-related cognitive and motor slowing. The central hypothesis of this study is that by enhancing dopamine functioning in the brain and improving cognitive and motor slowing, administration of carbidopa/levodopa (L-DOPA) will improve depressive symptoms in older adults.