Comparison of pramipexole versus ropinirole in the treatment of Parkinson’s disease

Parkinson’s disease is a progressive neurodegenerative disease characterized by motor and non-motor symptoms. Levodopa is the most effective drug in the symptomatic treatment of the disease. Dopamine receptor agonists provide sustained dopamin-ergic stimulation and have been found to delay the initiation of levodopa treatment and reduce the frequency of various motor complications due to the long-term use of levodopa. The primary aim of this study was to compare the efficacy of potent nonergoline dopamine agonists pramipexole and ropinirole in both “dopamine agonist monotherapy group” and “levodopa add-on therapy group” in Parkinson’s disease. The secondary aims were to evaluate the effects of these agents on depression and the safety of pramipexole and ropinirole. A total of 44 patients aged between 36 and 80 years who were presented to the neurology clinic at Ministry of Health Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey and were diagnosed with idiopathic Parkinson’s disease, were included into this randomized parallel-group clinical study. Dopamine agonist monotherapy and levodopa add-on therapy patients were randomized into two groups to receive either pramipexole or ropinirole. The maximum daily dosages of pramipexole and ropinirole were 4.5 mg and 24 mg respectively. Patients were followed for 6 months and changes on Unified Parkinson’s Disease Rating Scale, Clinical Global Impression-severity of illness, Clinical Global Impression-improvement, Beck Depression Inven­tory scores, and additionally in advanced stages, changes in levodopa dosages were evaluated. Drug associated side effects were noted and compared. In dopamine agonist monotherapy group all of the subsections and total scores of Unified Parkinson’s Disease Rating Scale and Clinical Global Impression-severity of illness of the pramipexole subgroup showed significant improvement particularly at the end of the sixth month. In the pramipexole subgroup of levodopa add-on therapy group, there were significant improvements on Clinical Global Impression-severity of illness and Beck Depression Inventory scores, but we found significant improvement on Clinical Global Impression-severity of illness score at the end of the sixth month in ropinirole subgroup too. The efficacy of pramipexole and ropinirole as antiparkinsonian drugs for monotherapy and levodopa add-on therapy in Parkinson’s disease and their effects on motor complications when used with levodopa treatment for add-on therapy have been demonstrated in several previous studies. This study supports the effectiveness and safety of pramipexole and ropinirole in the monotherapy and levodopa add-on therapy in the treatment of Parkinson’s disease.