Familial migraine with and without aura: clinical characteristics and co-occurrence

Migraine with aura (MwA) and migraine without aura (MwoA) are the two commo n forms of migraine. Many migraine patients suffer from both kinds of attac ks. In a questionnaire-based study using the current International Headache Society (IHS) criteria we determined the clinical characteristics and occu rrence of MwA + MwoA in 1000 migraine patients belonging to 210 Finnish mig raine families. Nine hundred and six patients were able to indicate whether they suffered from MwA (but not MwoA), migraine aura without headache (mig raine equivalent) (but not MwA) or MwA and MwoA. Of these patients, 3.2% ha d experienced MwoA, 11.1% MwA, 40.6% MwA + MwoA, 23.5% MwoA and 20.3% MwA-l ike symptoms not meeting the IHS criteria. The high prevalence of MwA attac ks in the families studied supports the belief that aura has a strong hered itary component. The MwA + MwoA patients had significantly more severe atta cks, more typical headache and more prodromal symptoms than the MwA and Mwo A subjects. Therefore, it is possible that there is a continuum with pure M wA at the neural and pure MwoA at the headache end of the spectrum, and MwA + MwoA lying in between the two. The MwA + MwoA patients would thus be lia ble to both types of migraine, making their attacks more characteristic and more severe. This would also explain why the co-occurrence of MwA and MwoA is more common in the clinic compared with population based epidemiologica l studies. These findings have consequences for future research on liabilit y genes for migraine.