Long-term prognosis of juvenile myoclonic epilepsy: A systematic review searching for sex differences

Purpose: Juvenile myoclonic epilepsy (JME), like other forms of idiopathic generalized epilepsy, shows a marked female predominance. However, few studies have specifically addressed the role of sex in its long-term prognosis. We performed a systematic review of the literature relevant to JME prognosis, focusing on sex-based differences in prognostic factors and outcome. Methods: A comprehensive literature search of the PubMed and Scopus databases was performed, considering all articles up to April 2020 in which long-term prognosis in JME had been explored and sex differences in outcome or prognostic factors were specified. Results: We included 25 articles published between 1984 and 2020. Sex differences in epilepsy outcome were explored by 21 of the 25 studies, but only three reported different outcomes in male vs female patients. All three found female sex to be associated with a later response to antiseizure medications, worse seizure control, and a higher risk of relapse in their entire study samples, which included JME patients. Eight studies found sex-based differences in possible predictors of long-term outcome: prolonged epileptiform EEG runs and the presence of eye closure sensitivity, both more frequent in women, were factors possibly linked to a poorer prognosis, as were praxis induction and generalized EEG asymmetric changes, which instead were more common in men. Valproate use, more frequent in men, was associated with a better outcome. Conclusion: Most studies do not highlight sex differences in JME prognosis. However, some sex specificities do emerge, especially with regard to particular reflex traits and EEG abnormalities. Finally, sex may condition therapeutic choices, and thus have a possible impact on long-term outcome.