Physicians treating Parkinson disease (PD) today are focused as much on minimizing the long-term consequences of PD as on immediate control of symptoms. The concept of “modifying” the natural history of a neurodegenerative disease has evolved because of the limitations of purely symptomatic therapies, the inexorable progression of disease, and a research initiative to understand the basic mechanisms of disease and develop appropriate ways to slow or halt neurodegeneration. Modifying the course of PD represents a spectrum of interventions that begins with therapies that treat the motor and nonmotor symptoms and reduce morbidity, mortality, and treatment-related complications and ends with interventions that are aimed at the underlying disease process, so called neuroprotective therapies. Dopamine agonists (DAs) have been part of PD therapy for many years, yet have only been recently studied for their potential to modify the course of PD. There is now overwhelming evidence that DAs, used early in the course of PD, modify the natural history of treated PD by reducing the incidence of dyskinesias and, in some cases, motor fluctuations. A more intriguing notion, for which some basic and clinical evidence exists, is that DAs also interfere with the underlying disease process.
Stern MB. Dopamine Agonists Modify the Course of Parkinson Disease. Arch Neurol. 2004;61(12):1969-1971. doi:10.1001/archneur.61.12.1969