Lennox–Gastaut syndrome in adulthood: Long-term clinical follow-up of 38 patients and analysis of their recorded seizures Aglaia Vignoli a,b , Gaia Oggioni a , Giovanni De Maria c , Angela Peron a,b, ⁎, Miriam Nella Savini a , Elena Zambrelli a , Valentina Chiesa a , Francesca La Briola a , Katherine Turner a , Maria Paola Canevini a,b a Epilepsy Center, San Paolo Hospital, Milan, Italy b Department of Health Sciences, Università degli Studi di Milano, Italy c Epilepsy Center, Spedali Civili, Brescia, Italy abstract article info Article history: Received 3 August 2017 Revised 4 September 2017 Accepted 10 September 2017 Available online xxxx Lennox–Gastaut syndrome (LGS) is a severe epileptic encephalopathy with childhood onset that usually con- tinues through adolescence and into adulthood. In the long term, patients with this condition still have intracta- ble seizures, intellectual disability, behavioral problems, and physical comorbidities. The aim of this study was to describe the clinical and EEG characteristics of a group of adults with Lennox–Gastaut syndrome. We identified 38 (22 females, 16 males) patients with LGS older than age 18 years at their last evaluation, with mean age of 43.3 ± 10.6 years. Median follow-up was 14.4 years (range: 2–40). All of our patients had 3 or more seizure types during their clinical history. The most prevalent seizure types at follow-up were atypical absences (28/38), tonic (28/38), generalized tonic–clonic (17/38), focal (11/38), and myoclonic seizures (9/38). All patients had drug-resistant seizures. Besides epilepsy, intellectual disability and behavioral problems were prominent features. Surprisingly, paroxysmal nonepileptic seizures were reported in 3 patients. Our observations confirm the poor outcome of Lennox–Gastaut syndrome through adulthood, regardless of age at seizure onset, etiology, and history of previous West syndrome. © 2017 Elsevier Inc. All rights reserved. Keywords: Lennox–Gastaut syndrome Long-term evolution Video-EEG recordings Drug-resistance Seizures 1. Introduction Lennox–Gastaut syndrome (LGS) is a rare age-related epileptic en- cephalopathy, characterized by multiple types of intractable seizures, cognitive and behavioral impairment, and typical electroencephalo- graphic (EEG) findings [1]. In the recent International League Against Epilepsy (ILAE) classifica- tion of the epilepsies, LGS is included in the new group of combined generalized and focal epilepsies, due to the fact that patients have both generalized and focal seizures [2]. The term “epileptic encephalop- athy” applies to LGS, since the epileptic activity itself contributes to se- vere cognitive and behavioral impairment, in addition to what is expected based on the underlying pathophysiology alone [3]. Although LGS usually begins in childhood (mainly before age 8 years, more rarely in adolescence or adulthood) [1], it usually con- tinues through adolescence and into adulthood. Several longitudinal and retrospective studies have documented the clinical and EEG evolu- tion of LGS [4–10], highlighting the high frequency of persistent and intractable seizures and the prevalence and relevance of intellectual disability (ID), behavioral problems and physical comorbidities, which often represent the main issues in patients' management [11]. In most studies, the number and variety of seizure types usually de- crease over time, although tonic seizures are reported to persist, espe- cially during sleep [10]. Conversely, evaluation of the EEG evolution showed that the typical pattern of diffuse fast rhythms during sleep was retained in adult LGS [7]. Despite the relatively high number of adult patients with LGS described, seizures have been characterized based on their caregivers' descriptions in most of them, and recorded only in few cases [8,10]. Due to the rarity of the syndrome (2–10/100,000) [12], we collected adult patients with LGS from two epilepsy centers in Northern Italy: the Regional Center for Epilepsy of the San Paolo Hospital in Milan and the Adult Epilepsy Center of the Spedali Civili in Brescia. Since video-EEG recordings of seizures in adulthood have been scarcely reported, the aim of our study was to describe the characteristics of seizures in an adult cohort of patients with LGS with long-term follow-up. 2. Methods Out of nearly 5500 patients with different types of epilepsies evalu- ated between 1992 and 2012, we selected patients with LGS with at least one evaluation at age N 18 years. Epilepsy & Behavior 77 (2017) 73–78 ⁎ Corresponding author at: Epilepsy Center, San Paolo Hospital, Dipartimento di Scienze della Salute, Università degli Studi di Milano, Via di Rudinì, 8, 20142 Milano, Italy. E-mail address: angela.peron@unimi.it (A. Peron). http://dx.doi.org/10.1016/j.yebeh.2017.09.006 1525-5050/© 2017 Elsevier Inc. All rights reserved. Contents lists available at ScienceDirect Epilepsy & Behavior journal homepage: www.elsevier.com/locate/yebeh