[Dopaminergic stimulation in the non-motor symptoms of Parkinson's disease]

The non-motor symptoms of Parkinson's disease have a great impact in terms of quality of life. They are frequently underdiagnosed and clinical experience suggests that not only is dopamine therapy ineffective but that in many cases it is also responsible for the appearance of some of these symptoms. Different studies have drawn attention to the involvement of the dopaminergic pathways in the pathogenesis of some non-motor symptoms. It has been observed that they can undergo fluctuations in relation to dopaminergic stimulation, generally in wearing off states, while displaying a significant correlation with motor fluctuations and a clinical response with continuous dopaminergic therapy.

Although recent reviews offer insufficient evidence for treatment of non-motor symptoms with dopaminergic therapy, involvement of the dopaminergic pathways in the aetiopathogenesis of some of these disorders and the clinical observation that such symptoms undergo fluctuations in relation to pulsatile dopaminergic stimulation may lead us to reconsider the possible role of dopaminergic therapy in the treatment of these symptoms.