Hemiplegic migraine with onset in childhood: The first multicenter Italian study

Objective: To describe the natural history of sporadic and familial hemiplegic migraines (SHM and FHM) with onset in the pediatric age. Methods: Retrospective observational study of 28 cases,visiting 9 Italian Centers for Juvenile Headache, diagnosed as SHM or FHM (ICHD-III b version, 2013) with onset under 16 years and with a longitudinal follow-up. Results: 28 cases (17 females, 11 males): 23 SHM (14 females, 9 male), 5 FHM (3 females, 2 male). Family history was positive for migraine without aura (5/28) or with aura non hemiplegic (8/28). Triggering factors were found in 13/28 cases. Age at HM onset: mean 10.1 y, range 4–16 y (5/28 cases under 6 y). Mean duration of aura was 11h 13’ (range 5’–48 h). Between HM attacks, neurologic examination was normal in 26/28 cases. At follow-up: mean age 16.9 y (range 6.5–47 y), mean duration of follow-up 8.1 y (range 2.5–38 y). The frequency of attacks ranged from 2 per month to less than 1 per year (mean 5–6 every year). During follow-up, FHM and SHM cases showed some differences: in cases with SHM attacks were less frequent but more severe while FHM patients had less intense but more frequent attacks and also a longer duration of disease. Preventive therapy for HM was prescribed to 12/28 cases. Conclusion: In the Literature data on the natural history of HM are quite limited, particularly in children. In the majority of our cases, the frequency and the type of attacks were quite variable, and in less than half of the cases trigger factors were identified. The majority of our patients had a good prognosis, even in cases with early onset of HM and/or prolonged and/or severe HM attacks. The natural history of SHM seems to differ from the FHM.