Pramipexole versus bromocriptine for levodopa-induced complications in Parkinson's disease.Cochrane Database Syst Rev. 2000CD
To compare the efficacy and safety of adjuvant pramipexole versus bromocriptine therapy in patients with Parkinson's disease, already established on levodopa and suffering from motor complications.
Electronic searches of MEDLINE, EMBASE and the Cochrane Controlled Trials Register. Handsearching of the neurology literature as part of the Cochrane Movement Disorders Group's strategy. Examination of the reference lists of identified studies and other reviews. Contact with Pharmacia Upjohn and Boehringer Ingelheim.
Randomised controlled trials of pramipexole versus bromocriptine in patients with a clinical diagnosis of idiopathic Parkinson's disease and long-term complications of levodopa therapy.
DATA COLLECTION AND ANALYSIS
Data was abstracted independently by the authors and differences settled by discussion. The outcome measures used included Parkinson's disease rating scales, levodopa dosage, 'off' time measurements and the frequency of drop outs and adverse events.
One randomised controlled trial has compared pramipexole with bromocriptine using a double-blind, parallel group, multicentre design. It was not powered to examine differences between active treatment arms. There was a larger reduction in off time with pramipexole therapy compared with bromocriptine (weighted mean difference 1.4 hours; 0, 2.8, 95% CI). No differences occurred in dyskinesia rating scale, dyskinesia as an adverse event or UPDRS complication score. The UPDRS ADL and motor scores showed similar improvements compared to placebo with both agonists. Levodopa dose reduction was similar with both agonists. Subscales of the Functional Status Questionnaire showed significant improvements compared to placebo with both agonists. The finding that the EuroQol improved significantly compared with placebo with pramipexole but not bromocriptine should be treated with caution. Dopaminergic adverse events were similar with each agonist, as was the all cause withdrawal rate.
Although pramipexole and bromocriptine improved off time and reduced parkinsonian motor impairments and disability compared with placebo, no conclusions regarding their comparative effectiveness and safety can be drawn as this single trial did not have adequate power to assess such differences. Further larger trials are required to examine this issue in the future.