Anti-depressants don't solve depression in patients with Parkinson's Disease 28 Aug 2007

Many patients with Parkinson's Disease continue to experience depressive symptoms despite taking anti-depressants.

This is the finding of the pan-European PRODEST study in 1,016 patients with Parkinson's disease (PD), which was presented at the 11th Congress of the European Federation of Neurological Societies (EFNS) in Brussels this week.

The study confirmed that depressive symptoms associated with PD are not only highly prevalent, but nearly half (44.1%) of patients receiving antidepressant treatment continued to experience depressive symptoms.

"These symptoms have a significant impact on PD patients' quality of life, often equal in impact to that of the traditionally better known motor symptoms of Parkinson's disease. The results suggest that many depressive symptoms are an expression of Parkinson's disease, rather than of a depressive syndrome," said Professor Paolo Barone, Department of Neurological Sciences, University of Napoli-Federico II, Naples, Italy and lead investigator of PRODEST.

"This consideration, if supported by further analysis of the PRODEST study results, might suggest different treatment approaches of depression in PD," he added.

In those 282 patients with a reported medical history of depression, the study results also showed that over half (54.3%) of these patients had a marked score in The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) with 66% receiving anti-depressant treatment, confirming a persistence of depressive symptoms despite treatment.

Data from recent studies with pramipexole, a non-ergot dopamineagonist, have shown a beneficial effect on the depressive and motivational symptoms in PD. Ongoing trials are aimed to confirm these previous findings.

Professor Matthias Lemke, M.D., Professor of Psychiatry and Medical Director at the Rheinische Kliniken, Bonn, Germany, said: "PD-related depressive symptoms can overlap or even be mistaken for motor symptoms. It is therefore important that physicians learn to differentiate these in order to find the optimal treatment for their PD patients. While pramipexole has proven an effective treatment for the motor symptoms of PD, there is now evidence that pramipexole may also improve PD-related depressive symptoms."

PD-related depressive symptoms have also been studied in an ongoing two-year Italian study, known as PRIAMO. Initial findings of the 55 centre study support the evidence that non-motor symptoms (NMS) are highly prevalent with the majority of patients experiencing one or more NMS. Psychiatric symptoms (anxiety and depression) were rated most frequently and with a high impact on patients' quality of life.

"The conclusions from PRIAMO further support the PRODEST study inhighlighting the need to address the often undiagnosed and under-treated aspects of Parkinson's disease which impart a significant burden on PD patients, relative to their disease severity," Professor Barone told the conference.