Drug-resistant idiopathic generalized epilepsy: A meta-analysis of prevalence and risk factors

•Pooled reported prevalence in IGE is 27% with a mean follow-up of 14 years.•Psychiatric comorbidities, combined three seizure types, the presence of absence seizure, generalized polyspike trains, status epilepticus, and catamenial epilepsy significantly increase the odds of drug resistance.•Further prospective cohort studies are needed to investigate the clinical and EEG factors to help complete the prognostic guidelines. Idiopathic generalized epilepsy (IGE) is a common epilepsy syndrome with early age onset and generally good seizure outcomes. This study aims to determine the incidence and predictive risk factors for drug-resistant IGE. We systematically searched three databases (PubMed, Embase, and Cochrane Library) in November 2022 and included 12 eligible studies which reported long-term outcomes (mean = 14.05) after antiseizure medications (ASMs) from 2001 to 2020. We defined drug resistance as the persistence of any seizure despite ASMs treatment (whether as monotherapies or in combination) given the criteria of drug resistance varied in original studies. A random-effects model was used to evaluate the prevalence of refractory IGE. Studies reporting potential poor prognostic factors were included for subsequent subgroup meta-analysis. The pooled prevalence of drug resistance in IGE cohorts was 27% (95% CI: 0.19–0.36). Subgroup analysis of the risk factors revealed that the psychiatric comorbidities (odds ratio (OR): 4.87, 95% confidence interval (CI): 2.97–7.98), combined three seizure types (absences, myoclonic jerks, and generalized tonic-clonic seizures) (OR: 5.37, 95% CI: 3.16–9.13), the presence of absence seizure (OR: 4.38, 95% CI: 2.64–7.28), generalized polyspike trains (GPT) (OR: 4.83, 95% CI: 2.42–9.64), sex/catamenial epilepsy (OR: 3.25, 95% CI: 1.97–5.37), and status epilepticus (OR: 5.94, 95% CI: 2.23–15.85) increased the risk of poor prognosis. Other factors, including age onset, family history, and side effects of ASMs, were insignificantly associated with a higher incidence of refractory IGE. Drug resistance is a severe complication of IGE. Further standardized research about clinical and electroencephalography factors is warranted.