Page 118 - Migraine, the heart and the brain

Chapter 7
baCkground
A range of clinical neurophysiological and functional imaging studies have suggested that migraine might be associated with cerebellar dysfunction (1–10). However, these studies were all conducted in patients who were selected from headache clinics and thus likely are on the more severe end of the clinical spectrum. Moreover, tests were not analysed blinded for diagnosis, and most migraine patients were using antimigraine medications potentially interfering with cerebellar function. Therefore, it is still uncertain whether migraine is associated with cerebellar dysfunction, and, if so, to what extent and why? Is cerebellar dysfunction due to the increased prevalence of cerebellar ischaemic lesions in migraine patients or is there a more functional explanation similar to what’s seen in familial hemiplegic migraine type 1 (FHM1) (11,12)? Although a systematic quantitative assessment of cerebellar function in FHM has never been conducted, many FHM1 patients have signs of cerebellar ataxia on clinical examination (13). In the present study we systematically and quantitatively assessed in detail (i) motor and non-motor cerebellar function, (ii) presence and distribution of ischaemic lesions in the cerebellum and other parts of the brain, and (iii) the relationship between cerebellar lesions and dysfunction in 200 unselected patients with migraine with or without aura from the general population. The results were analysed blinded for diagnosis and compared with those obtained in 82 non- migraine control individuals and, as a positive control, 13 patients with genetically proven FHM1.
methods
Participants
Individuals with migraine with aura (n =111, MA) or without aura (n=89,MO) and non- migraine controls (n=82) were all participants from the population based Cerebral Abnormalities in Migraine, an Epidemiological Risk Analysis Cohort (CAMERA II) study, which was primarily aimed at assessing longitudinal progression of brain lesions on magnetic resonance imaging (MRI) (14). All participants were invited to undergo cerebellar functions tests on the day MRI was performed. Participants were allowed to complete some or all tests, according to available time on the test occasion. No speci c selection criteria were used. The study individuals were not informed about the speci c goals of each test to avoid selection bias. Fifteen patients with
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