Migraine and stroke risk in the perinatal period

Migraines have been associated with increased risk of maternal stroke in the perinatal period.

Hypertensive disorders have been hypothesized to mediate the association; however,

to our knowledge, this has not been formally quantified.

The objective of anew study (Gretchen Bandoli, PhD1; Rebecca J. Baer, MPH2; Dawn Gano, MD, MAS3; et al) was to determine the extent to which hypertensive disorders mediate the association between migraines and maternal stroke.

They queried a retrospective California birth cohort of 3 million singleton, live births between January 2007 to December2012 created from linked birth certificates and hospital discharge summaries.

There were 26 440 women with a diagnosis of migraine (914/100 000 deliveries).

Strokes occurred in 843 women (29/100 000 deliveries); ischemic strokes were 58% of all stroke events.

Women with migraines were more likely to be non-Hispanic white, have private insurance, have obesity, have diabetes (preexisting or gestational), have amental health disorder, use tobacco, and use drugs or alcohol

Women with migraines during pregnancy were more likely to have a hypertensive disorder (15.1% vs 7.0%; adjusted risk ratio [aRR], 1.6; 95% CI, 1.6-1.7), a stroke during pregnancy or delivery (0.15% vs 0.01%; aRR, 6.8; 95% CI, 4.7-9.8), or a stroke post partum (0.05% vs 0.01%; aRR, 2.1; 95% CI, 1.2-3.7).

Although the numbers were small, the effects were twice as strong in models for ischemic stroke compared with hemorrhagic stroke

Similar to previous work both in pregnant and nonpregnant women, they found an elevated risk of stroke among women with migraines.

Approximately one-fourth of the excess cases of maternal stroke associated with migraine were attributable to hypertensive disorders. This suggests that other pathways exist between migraine and stroke during the perinatal period, potentially through pathophysiologic changes, such as increased blood volume and cerebral circulation