Risk of Stroke, Pulmonary Embolism, and Deep Vein Thrombosis Increased in Patients with Peripartum Migraines

Lindsey R. Perez, Pharm.D. Candidate, The University of Texas at Austin
ClotCare Editorial Review by Henry I. Bussey, Pharm.D., FCCP, FAHA May, 2009

Reference: Bushnell CD, Jamison M, James AH. Migraines during pregnancy linked to stroke and vascular diseases: US population based case-control study. BMJ. 2009; 338:b664.

Among 18 million pregnancies, the rate of migraine codes was 185 per 100,000 deliveries. Stroke was 15.8 times more common (odds ratio) in those with a migraine diagnosis. This included a strong association specifically with ischemic stroke (odds ratio 30.7). Pulmonary embolism and deep vein thrombosis also were associated with peripartum migraine (odds ratio 3.1 and 2.4, respectively).

Migraine headache sufferers may experience a reduced severity or frequency of episodes during the peripartum period. However, migraines during pregnancy are still a concern which may prompt a hospital admission and may be linked to vascular complications.

This study was a case-control study of a United States population inpatient sample from the Healthcare Cost and Utilization Project of the Agency of Healthcare Research and Quality. The study examined over 18 million pregnancy related discharges over a three year period. Diagnoses of migraine were identified by International Classification of Diseases, 9th revision (ICD-9) codes and subsequently linked to ICD-9 codes for stroke and other vascular diseases. In order to directly associate migraines to individual vascular diseases, pre-eclampsia diagnoses were excluded.

While the strong association between peripartum migraines and vascular complications is a valid concern, there is a lack of ability to determine which factor is the preceding event. Noted study limitations include the reliability of evaluating ICD-9 codes. Nonetheless, the results should urge clinicians to consider ruling out stroke and vascular complications in peripartum patients presenting with migraine headaches.