Page 165 - Migraine, the heart and the brain

This thesis describes the results of studies on subjects with migraine and controls without migraine within the population based “Cerebral abnormalities in migraine an epidemiological risk analysis II (CAMERA II) study”. These studies include longitudinal brain imaging (part I), right-to-left shunt (RLS) investigation (part II), and cognitive and cerebellar function evaluation (part III). Two clinical based studies are also included; 1) to evaluate the transient effects of the acute migraine attack on cognitive function and 2) to investigate an association between non-shunting cardiac abnormalities and migraine aura.
i migraine and brain imaging
In our population-based cohort that was followed up after 9 years, women with migraine had a higher volume of deep white matter hyperintensities and also more new lesions. This was not related to the presence of aura symptoms. Measures of migraine severity (eg attack frequency or life time attack load) were not related to progression of brain lesions. In men no difference between migraineurs and controls in deep white matter volume nor progression was found. (Chapter II) The prevalence of infratentorial hyperintensities was also higher in female migraineurs (both with and without aura) than in controls. Also progression of infratentorial hyperintensities during follow up was more frequent in migraineurs (trend). Again this was not found in men. (Chapter II)
White matter hyperintensities are common with age and increase over time. They are
likely ischemic in origin, probably caused by chronic hypo-perfusion at borderzones of
vessels and arteriolosclerosis. 1;2 Recently, it was shown that, like in the acute state of
ischemia, a border zone with decreased cerebral blood flow, the so called penumbra,
surrounds white matter hyperintensities in general, also suggesting an ischemic
origin.3 In our study, female migraineurs were found to have more progression 9 of supratentorial deep white matter lesions and infra-tentorial hyperintensities,
not speci c for a migraine subtype. These ndings somewhat differ from those in a meta-analysis of six population-based and 13 clinical-based studies, in which an increased risk was only present in migraine with aura, and not as in our study in both migraine with and without aura.4 However studies included in this meta-analysis were heterogeneous, and often did not distinguish between deep and peri-ventricular white matter lesions which is important as their origin is hypothesized to be quite
Summary and general discussion
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