Role of dopaminergic agonists

The usefulness of an initial treatment of Parkinson's disease with a dopami ne agonist has now been studied for more than 20 years. The first clinical trials compared the long-term out come of patients receiving early bromocri ptine or lisuride to those receiving initial L-dopa. These pilot data sugge sted that the early use of these agonists (combined early or supplemented l ater with low doses of L-dopa) reduced the risk of occurence of motor compl ications such as dyskinesia and/or fluctuations. These initial conclusions were however criticised because of methodological limitations in study desi gn. The recent results from new large prospective randomized double-blind 5 -year L-dopa-controlled trials using newer dopamine agonists (cabergoline a nd ropinirole) confirmed the findings of the previous pilot studies. Theref ore. one now generally agrees that the early use of such agonists (to which low doses of L-dopa may be added as a second step if necessary to maintain an adequate control of parkinsonian symptoms) is useful to reduce the risk of occurence of motor complications. This result is achieved without a maj or increase in the risk of other dopaminergic adverse events (digestive, ca rdiovascular, psychiatric), specially in "young" patients (before 70 years) .