Page 14 - Migraine, the heart and the brain

Chapter 1
Not only clinical brain infarcts (that cause noticeable symptoms), but also silent brain infarcts (without any noticeable symptoms) have been associated with migraine.16 Clinical imaging studies in migraine patients also suggested that the risk of silent white matter brain lesions (not strati ed for deep or peri-ventricular location) was increased four times among migraineurs compared to controls. In this study gender or migraine subtype were not speci ed.17 It is not known if clinical infarcts, silent infarcts and white matter lesions share the same pathophysiological mechanism. Because earlier studies had methodological limitations and were mostly clinic-based, likely investigating a more severe migraine phenotype, results could have been biased. An unbiased, population-based study, assessing the prevalence of silent infarcts and white matter brain lesions in a wide spectrum of migraine patients from the general population was required.
baCkground and outline of this thesis
To investigate the association between both silent infarcts, white matter lesions and migraine the Cerebral Abnormalities in Migraine, an Epidemiological Risk Analysis (CAMERA-I) study was performed from 1999-2000. For this study subjects with migraine and controls aged 30 to 60 years were randomly selected from the Genetic Epidemiology of Migraine (GEM) study. The GEM study was a large population study in the 90ths in two county population registries in the Netherlands to assess the prevalence of migraine.6 Migraine patients were identi ed with a three- step procedure including a semi-structured interview by telephone. The lifetime prevalence of migraine in women was 33% and in men 13% and migraineurs suffered a median of 12 migraine attacks per year; 25% had at least two attacks per month. For the CAMERA-I study brain magnetic resonance imaging (MRI) was performed in 435 participants (134 patients with migraine without aura, 161 patients with migraine with aura, and 140 controls). The CAMERA-I study demonstrated a higher prevalence and greater volume of deep white matter hyperintensities, infratentorial hyperintensities, and posterior circulation territory infarcts in participants with migraine.18;19 In migraineurs with a higher attack-rate, the risk of lesions was higher, which was found suggestive of a potential causal relationship. But, because this was a cross-sectional study no causal relationship could be established. The ndings from the CAMERA-I study thus raised several questions;
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