No association between migraine frequency and white matter lesions and silent brain infarctions: a study in a series of chronic migraine women.

BACKGROUND AND PURPOSE: It has been suggested that silent infarctions (SI) and hyperintense white matter lesions (WML) are related to migraine frequency. We studied their prevalence and anatomical distribution in chronic migraine (CM) patients. METHODS: 96 CM (mean age 43; range 16-65 years) and 29 episodic migraine (EM) women (36, 16-58 years) underwent a 1.5 T MRI following CAMERA protocol. Number, size and location of SI and deep WML (dWML) were recorded and a modified Fazekas scale was applied to assess periventricular WML (pWML). RESULTS: WML were found in 59 (61.5%) CM and 17 (58.6%) EM women (OR= 1.13; 95% CI 0.48-2.62, p= 0.784). The majority (63% CM and 71% EM) were small dWML. Exclusive pWML were exceptional. Of the 739 WML seen in CM patients, 734 (99.3%) were hemispheric and mostly frontal (81%). Posterior fossa WML were seen in only 5 (0.7%) CM (always in the pons) and 2 (2.1%) EM women. Age >45 was the only vascular risk factor (VRF) associated with a higher WML number (medians of 0 45 years, p= 0.004). We found 7 SI in 6 CM women (6.5%). CONCLUSIONS: As compared with the expected prevalence at this age, this study confirms that the prevalence of WML, in most cases small, deep and frontal, is increased in CM and EM. However, our results do not support an association of WML or SI with a higher frequency of attacks, but with the presence VRF and mainly age > 45 years.