Despite the negative effects of depression in Parkinson's disease, there is currently no evidence-based standard of care. The purpose of this study was to examine the efficacy of individually administered cognitive-behavioral therapy (CBT), relative to clinical monitoring (with no new treatment), for depression in this medical population.

Eighty depressed (based on DSM-IV criteria) patients with Parkinson's disease participated in a randomized, controlled trial of CBT relative to clinical monitoring (1:1 ratio) in an academic medical center from April 2007 to July 2010. All patients continued to maintain stable medication regimens under the care of their personal physicians. The 17-item Hamilton Depression Rating Scale (HAM-D) total score was the primary outcome. CBT was modified to meet the unique needs of the Parkinson's disease population and provided for 10 weeks. Assessments were completed by blind raters at baseline and 5 (midpoint), 10 (end of treatment), and 14 weeks (follow-up evaluation) postrandomization.

The CBT group reported greater reductions in depression (change in HAM-D score) than the clinical monitoring group. At week 10, the mean HAM-D score change was 7.35 for CBT relative to 0.05 for clinical monitoring. CBT was also superior to clinical monitoring on several secondary outcomes (i.e., Beck Depression Inventory scores, anxiety, quality of life, coping, Parkinson's disease symptom ratings). There were more treatment responders in the CBT group than the clinical monitoring group (56% versus 8%, respectively).

CBT may be a viable approach for the treatment of depression in Parkinson's disease. Further research is needed to replicate and extend these findings.