The main pathologic and biochemical characteristic of Parkinsons disease is the selective cell death of dopaminergic neurons in the midbrain area called substantia nigra and marked decrease in dopamine neurotransmitter produced by these neurons.
In a study conducted by the Parkinson Study Group and led by investigators at the Institute for Neurodegenerative Disorders in New Haven, Conn., the rate of this dopaminergic degeneration after early treatment with the drugs pramipexole and levodopa, administered to 82 early Parkinsons patients, was compared using brain imaging.
Our data suggest that patients initially treated with pramipexole experience a significantly slower rate of loss of dopaminergic neuronal functioning compared to those treated with levodopa, said study author Kenneth Marek, MD. While there remains debate about treatment for early Parkinsons disease -- and all treatment should be individualized to meet the needs of the patient this study adds important new information to the growing body of knowledge on the early treatment of Parkinsons disease.
Ultimately, most patients will be treated with both levodopa and a dopamine agonist, Marek said.
Marek cautions that further, long-term study comparing the clinical endpoints of these drug therapies relative to Parkinsons progression will be required to assess the clinical impact of these imaging findings.