Bilateral independent periodic discharges are associated with electrographic seizures and poor outcome: A case-control study

• Authors: Gamaleldin Osman, Henry Ford Hospital; Rahul Rahangdale, Yale University; Jeffrey W. Britton, Mayo Clinic; Emily J. Gilmore, Yale University; Hiba Haider, Emory University; M. Brandon Mendoza, Emory University
• Journal Title: Clinical Neurophysiology
• Volume: Volume 129, Number 11
• Publisher: Elsevier Ireland Ltd | 2018-11-01, Pages 2284-2289
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1016/j.clinph.2018.07.025
• Subjects: Biology, Neuroscience
• Keywords: Science & Technology; Life Sciences & Biomedicine; Clinical Neurology; Neurosciences; Neurosciences & Neurology; Bilateral independent periodic discharges; Periodic discharges; Seizures; Continuous EEG monitoring; LATERALIZED EPILEPTIFORM DISCHARGES; CLINICAL-SIGNIFICANCE; EEG

Abstract

Objective: To determine the clinical correlates bilateral independent periodic discharges (BIPDs) and their association with electrographic seizures and outcome. Methods: Retrospective case-control study of patients with BIPDs compared to patients without periodic discharges (“No PDs”) and patients with lateralized periodic discharges (“LPDs”), matched for age, etiology and level of alertness. Results: We included 85 cases and 85 controls in each group. The most frequent etiologies of BIPDs were stroke, CNS infections, and anoxic brain injury. Acute bilateral cerebral injury was more common in the BIPDs group than in the No PDs and LPDs groups (70% vs. 37% vs. 35%). Electrographic seizures were more common with BIPDs than in the absence of PDs (45% vs. 8%), but not than with LPDs (52%). Mortality was higher in the BIPDs group (36%) than in the No PDs group (18%), with fewer patients with BIPDs achieving good outcome (moderate disability or better; 18% vs. 36%), but not than in the LPDs group (24% mortality, 26% good outcome). In multivariate analyses, BIPDs remained associated with mortality (OR: 3.0 [1.4–6.4]) and poor outcome (OR: 2.9 [1.4–6.2]). Conclusion: BIPDs are caused by bilateral acute brain injury and are associated with a high risk of electrographic seizures and of poor outcome. Significance: BIPDs are uncommon but their identification in critically ill patients has potential important implications, both in terms of clinical management and prognostication.