Dopamine and migraine: does Parkinson's disease modify migraine course?

As brainstem mechanisms and dopaminergic neurotransmission are involved in migraine pathophysiology, we decided to investigate the course of migraine in Parkinson's disease (PD), the paradigm of brainstem dopaminergic disease. We screened 237 consecutive PD out-patients by direct interview to assess the prevalence of lifetime and current migraine. Moreover, we compared the course of migraine in PD patients with that of otherwise healthy age- (+/- 3 years) and sex-paired migraine controls in a cross-sectional study. PD patients showed a lifetime migraine prevalence of 27.8% and a current migraine prevalence of 13.1%. A positive family history of migraine was less frequent in PD patients than in controls. The frequency of current migraine was significantly lower in PD patients than in controls (47.0% vs. 68.2%; odds ratio = 0.41, 95% confidence interval = 0.19-0.89). Approximately two-thirds of PD patients reported an improvement in or remission of migraine after PD onset. Effects of menopause on migraine course were similar in patients and controls. These findings suggest that PD might somehow shorten the clinical course of migraine. Possible explanations include a prolonged prophylactic effect by chronic dopaminergic therapy or a positive effect of PD pathophysiology, namely nigral degeneration, on migraine mechanisms.