The January 28, 2004, issue of the Journal of the American Medical Association (JAMA) included an article that captured the attention of the media and generated reports all over the Internet. The article, "Migraine as a Risk Factor for Subclinical Brain Lesions,"1 reported on a study conducted in the Netherlands.
It has been suggested that Migraines may be an independent risk factor for stroke, but some in the medical community had considered consistent data lacking. I asked Terri Miller Burchfield, Co-Founder and Vice President of MAGNUM, why previous studies hadn't been given more in-depth consideration. She explained, "Although there have been many case studies and clinical studies, there always seemed to be issues regarding them that the medical community couldn't agree on.
Studies of patients with Migrainous stroke exist, but data regarding the prevalence of subclinical (not causing any symptoms) infarcts (An area of tissue that undergoes necrosis due to cessation of the blood supply. In the brain, an infarct may contribute to a stroke.) in Migraine patients has been lacking. The study was to investigate whether Migraineurs from the general population are at increased risk of brain infarcts and white matter lesions (WMLs) (Areas of pathologically altered tissue in the nerve tissue of the spinal cord and brain.) or whether this risk varies by Migraine subtype and attack frequency.
Some of the findings:
- A total of 60 brain infarcts were detected in 31 study participants. Proportionately more Migraineurs had at least one infarct compared with controls. "However, in the cerebellar region of the posterior circulation territory (PCT), patients with Migraine had a higher prevalence of infarct than controls [5.4 percent vs. 0.7 percent; more than seven times the risk],"
- The risk of posterior circulation territory infarcts was 7.1 times higher in the Migraineurs than the control patients.
- Migraine with aura was associated with significantly increased PCT infarcts, but not Migraine without aura.
- "The adjusted OR was 13.7 (95% CI, 1.7-112) for patients with migraine with aura compared with controls. In patients with migraine with a frequency of attacks of 1 or more per month, the adjusted OR was 9.3 (95% CI, 1.1-76). The highest risk was in patients with migraine with aura with 1 attack or more per month (OR, 15.8;95%CI, 1.8-140)."1
- Among women, compared with controls, Migrainuers had a significantly increased risk of high DWML (dense white matter lesion) load... that was similar for patients with migraine without aura... and patients with migraine with aura...This risk increased with increasing attack frequency...; compared with controls, female migraine patients with fewer than 1 attack per month had an OR (odds ratio) of 1.6 (95% CI, 0.8-3.5) and those with 1 or more attack per month had an OR of 2.6 (95% CI, 1.2-5.7)."1
- The group with migraine with aura and 1 or more attack per month had the highest risk of PCT infarct.