Abnormal facilitatory mechanisms in motor cortex of migraine with aura

Motor coordination impairment and migraine in children: a new comorbidity?

Migraine without aura (MoA) could be considered the most frequent form of primary headache in children, associated with many known comorbidities, but only the recent literature has begun to consider the importance of motor impairment linked to the attacks. The developmental coordination disorder (DCD) is a very common problem among children, with a prevalence ranging up to 19 %. The aim of this study was to evaluate the presence of motor coordination impairment in a population of children affected by MoA, and its role as putative risk factor for motor skills impairment. This observational study was performed in the Clinic of Child and Adolescent Neuropsychiatry of the Second University of Naples. MoA was diagnosed according to the International Classification of Headache Disorders (IHS-2) criteria. The study population consisted of 27 patients affected by MoA (16 females, 11 males) (mean age: 8.7 ± 2.15 years) and 59 typically developing children (34 females, 25 males) (mean age: 8.0 ± 2.1 years). The whole population underwent a clinical evaluation in order to assess the total IQ level, the visual motor integration skills, and the presence of DCD. Our results showed that MoA children had more impairments in motor coordination (p < 0.001) and visual motor integration (p < 0.001) than control group. To our knowledge, this is the first study to assess the association of poor motor coordination and MoA in children using objective measurements. These findings suggest a new perspective in the management of migraine disease in children, pinpointing that the relationship between DCD and migraine could represent a not yet understood or identified comorbidity, even if further reports are necessary, and that migraine probably could be considered not only a painful syndrome in future.

Beta-blocker migraine prophylaxis affects the excitability of the visual cortex as revealed by transcranial magnetic stimulation

The objective of this study is to assess effects of beta-blocker migraine prophylaxis on cortical excitability determined by transcranial magnetic stimulation (TMS). Phosphene and motor thresholds (PT, MT) were investigated in 29 patients with migraine, in 15 of them prior to and following preventive medication with metoprolol and in 14 patients without prophylaxis. Following prophylaxis headache frequency significantly decreased (p = 0.005) and mean PT were significantly increased (51.5 ± 7.5 vs. 63.6 ± 8.4%) compared to patients without preventive treatment (53.7 ± 5.3 vs. 52.3 ± 6.3%; p = 0.040). Mean MT did not significantly differ either between groups or due to treatment. In the group of all patients, a significant inverse correlation between headache frequency and the level of PT was found (R = -0.629; p < 0.01). There was, however, no significant correlation in the subgroups of patients. We conclude that (a) clinical efficacy of beta-blocker treatment in migraine could be (at least partly) linked to its ability to modulate the excitability of the visual cortex and (b) the PT determined by TMS appears suitable to assess the effects of prophylaxis on cortical excitability in the individual patient. This may be useful in clinical trials investigating migraine preventive drugs.