Antidepressants Don't Worsen Parkinson's Symptoms
Irene H. Richard, MD, from the University of Rochester in New York, and colleagues conducted a double-blind, placebo-controlled trial of 115 patients who were randomized to receive a selective serotonin reuptake inhibitor (paroxetine, maximum daily dose of 40mg), a serotonin and norepinephrine reuptake inhibitor (venlafaxine XR, maximum daily dose of 225mg), or placebo. Subjects were followed for 12 weeks, with dosage adjustment during the first six weeks and then six weeks of maintenance therapy. Subjects met Diagnostic and Statistical Manual of Mental Disorders, 4th Edition criteria for depression and scored >12 on the first 17 items of the Hamilton Rating Scale for Depression (HAM-D). Change in the HAM-D score at week 12 compared with baseline was assessed.
The researchers found that patients in the paroxetine group showed a significant mean 12-week reduction (6.2 points) in the HAM-D score, compared with the placebo group, as did the venlafaxine XR group (4.2 points). No treatment effects on motor function were reported.
"Both paroxetine and venlafaxine XR significantly improved depression in subjects with Parkinson's disease," the authors write.
Several authors report financial ties to pharmaceutical companies, including Wyeth Pharmaceuticals and GlaxoSmithKline, both of which provided the study medications.