Reduction in the Intensity of Abortive Migraine Drug Use During Coumarin Therapy

OBJECTIVE: To investigate the impact of coumarin therapy on migraine attack frequency. BACKGROUND: Sporadic case reports and clinical studies have described beneficial effects of coumarin therapy on migraine severity. DESIGN AND METHODS: A retrospective follow-up study based on a prescription database covering a population of 450 000 was conducted. All patients using an abortive migraine drug (ergotamine or sumatriptan) and subsequently treated with either coumarin (index group) or low-dose acetylsalicylic acid (control group) were analyzed. The impact of coumarin and low-dose acetylsalicylic acid on the frequency of migraine attacks was assessed by measuring the intensity of ergotamine and sumatriptan use, in defined daily doses per month per patient, before and during coumarin or acetylsalicylic acid treatment. In addition, a "therapeutic intensity reduction" was determined for each patient. RESULTS: The study population consisted of 92 patients; 35% had been prescribed coumarin and 65% had been prescribed low-dose acetylsalicylic acid after the initiation of ergotamine or sumatriptan. Two thirds of the study population was treated with ergotamine. Overall, ergotamine and sumatriptan use for the coumarin cohort decreased from 6.4 defined daily doses per month prior to coumarin treatment to 3.0 defined daily doses during coumarin treatment, compared with a reduction from 5.2 defined daily doses per month to 4.4 defined daily doses per month for the low-dose acetylsalicylic acid cohort (P>.05). The therapeutic intensity of ergotamine and sumatriptan use was significantly decreased by 40% for the coumarin cohort, compared with 4.7% for the low-dose acetylsalicylic acid cohort (P=.004). CONCLUSIONS: We observed that coumarin treatment was clearly associated with a reduction in the therapeutic intensity of abortive migraine drug use in comparison with low-dose aspirin treatment. This suggests that, overall, the coumarin cohort had experienced a substantial reduction in the frequency of migraine attacks during anticoagulation treatment. Our findings, as well as those of others, justify a controlled clinical trial to further establish the effects of coumarin therapy on migraine severity and its possible role in the prophylactic management of patients suffering from migraine.