Migraine sufferers may be at increased risk of stroke

Migraine may be an independent risk factor for ischaemic stroke, say the authors of a recent systematic review and meta-analysis.The results of studies investigating the risk of stroke in people with migraine have been inconsistent. Therefore, researchers conducted a systematic review and meta-analysis of data from 11 case control studies and three cohort studies in order to quantify the risk of ischaemic stroke in people with migraine (with or without aura) and to assess the level of this risk in different age groups and in women using oral contraceptives. The results of the analysis suggest that people with all types of migraine are at increased risk of ischaemic stroke (relative risk = 2.16 [1.89-2.48]). The relative risks of ischaemic stroke in migraine sufferers with and without aura were found to be 2.27 (1.61-3.19) and 1.83 (1.06-3.15), respectively. The degree of risk did not vary across different age groups.The analysis showed an approximately eight-fold increase in the risk of stroke in women using oral contraceptives compared with women not using these agents (relative risk = 8.72 [5.05-15.05]). The researchers point out that although the risk of stroke associated with oral contraceptive use appears to be very high the figure is based on the findings of just three studies. In other studies in women using oral contraceptives around a two-fold increase in stroke risk has been observed in those with a history of migraine. The researchers conclude that their findings strongly suggest that migraine may be an independent risk factor for stroke, recommending that that more studies be conducted in order to determine the mechanism behind this potential association.They add that, given the prevalence of oral contraceptive use in young women, further investigation into the potential risk of stroke in migraine sufferers using oral contraceptives is also required. Reference...