Use and Misuse of Domperidone in Parkinson's Disease in France - Observational

Parkinson disease is the second most frequent neurodegenerative disease after Alzheimer disease and affect 1% of the population over 60 years. The treatment of PD is based on dopamine replacement therapies (DRT). Nausea is the most frequent adverse event whatever the drug, occurring in 30-40% of patients at the initiation of DRT. Domperidone, a dopamine D2 receptor antagonist with antiemetic properties, does not readily cross the blood-brain barrier, allowing its used in PD. Domperidone may prolong the duration of the QT interval in predisposed patients, and has been associated with proarrhythmia and arrhythmic deaths. Arrhythmias, sudden death and cardiac arrest were reported with high intravenous doses which has led to withdraw of the parenteral form of the drug in 1984. Two case control studies found an increased risk of sudden death associated with domperidone use. In these reports, the increased risk was depending on age, dose, and the use of domperidone in combination with CYP3A4 inhibitors. Following the discussion created by this alert, the PRAC of the EMA has issued recommendations restricting domperidone use to patients younger than 60 years at doses below 30 mg/day and for a short period (7 days). Because there is no alternative antiemetic drug to be used in PD, domperidone is commonly prescribed as a preventive therapy in most PD patients initiating DRT. In this population, usually older than 60 years, doses of 60 or 80 mg/day are commonly prescribed, for at least 2 months of the DRT escalating dose period or longer. A particular "niche" of domperidone misuse might be patients treated with continuous subcutaneous administration of apomorphine, a second line therapy in PD, inducing severe and prolonged nausea in almost all patients. Little is known about the use of domperidone in PD in France, but misuse of domperidone in PD patients is probably very high. Data collected from two French PD cohorts, COPARK and DIGPD, showed that 8-14% of PD patients were treated with domperidone. The aim of this proposal is to conduct a cross sectional observational study performed in consecutive patients followed by the 24 PD expert centers of the NS Park network, general hospitals and private practice neurologists, to describe the actual use of domperidone in PD patients.