Effects of the dopamine agonist pramipexole on depression, anhedonia and motor functioning in Parkinson's disease.

Depression affects approximately 45% of all patients with Parkinson's disease, reduces quality of live independent of motor symptoms and seems to be underrated and undertreated. Pramipexole shows D(3)- versus D(2)-receptor preference at cortico-frontal dopamine receptors and neurotrophic effects which seem to relate to its antidepressant and anti-anhedonic properties in Parkinson's disease and bipolar depression found in controlled studies. In the present study, effects of pramipexole were investigated under routine clinical conditions. Anhedonia was measured in patients with Parkinson's disease (n=657) using the self-rated Snaith-Hamilton-Pleasure-Scale (SHAPS-D), depression was assessed by the observer-rated Short-Parkinson's-Evaluation Scale (SPES). Anhedonia was present in 45.7% of all patients and in 79.7% of the depressed patients with Parkinson's disease. Mild depression was present in 47%, moderate to severe depression in 22% of the patients. At the end of the study period of 9 weeks on an average, the mean dosage of pramipexole was 1.0+/-0.6 mg/d (range 0.3 to 4.2). Frequency of depression (moderate to severe: 6.8%, mild: 37.6%) and anhedonia (25.5%) as well as motor deficits were significantly reduced during treatment with pramipexole. Drop-outs due to adverse events occurred in 3.5%. Future studies should investigate specificity of anti-anhedonic and antidepressive properties of pramipexole.

Anhedonia, depression, and motor functioning in Parkinson's disease during treatment with pramipexole.

Anhedonia, a core symptom of depression, correlates with motor alterations in major depressive disorder and has been assumed to be frequent in depressed patients with Parkinson's disease (PD). In the present study, the authors assessed for the first time frequency of anhedonia in patients with idiopathic Parkinson's disease (N = 657) and the relationship of anhedonia and parkinsonian motor deficits during treatment with pramipexole. Mild depression was present in 47% of the patients and moderate to severe depression in 22%. Anhedonic individuals included 45.7% of all patients and 79.7% of depressed Parkinson's disease patients. Anhedonic Parkinson's disease patients had greater motor deficits, restrictions in activities of daily living, and depression compared to nonanhedonic patients. Frequency of anhedonia and depression was significantly reduced during treatment with pramipexole. Future studies should further investigate antianhedonic efficacy of dopamine agonists including pramipexole in depressed patients with Parkinson's disease.