PNES Epidemiology: what is known, what is new?

Abstract Psychogenic non-epileptic seizures (PNES) are clinically defined as events resembling epileptic seizures but presumed to be not conscious and an involuntary expression of emotional distress similar to panic attacks. Their neurobiological physiopathology is different. However, PNES-like states are recognized in some cultures as a cultural phenomenon. PNES rank among the top three neuropsychiatric problems and are targeted by an International League Against Epilepsy Task Force that published in 2017 an actualization concerning PNES epidemiology renewing the interest concerning PNES. Studies concerning PNES are complicated: these patients are difficult to identify, and a have tendency to disengage from medical services after diagnosis. The incidence and prevalence estimates in the literature are based on diagnoses from tertiary care epilepsy monitoring units, where approximately 20 to 40% of adult patients and 10 to 23% of children presenting with “drug-resistant epilepsy” are diagnosed with PNES, making the incidence of PNES to be 1.4–4.9 cases per 100,000 people per year and the prevalence range of 2–33/100,000 However, epilepsy can be associated with PNES with estimated comorbidity range from 5 to 50%. 75% of patients with PNES are young adult women. PNES are uncommon under 6 and after 50 years of age. The female predominance is classically not found in children, late-onset or intellectual disability (ID) subgroups (about 10% PNES patients). Psychiatric comorbidities such as anxiety, post traumatic stress disorders and history of trauma are frequent in PNES patients.One recent change concerning the epidemiology of PNES is the awareness that this condition is present worldwide, and not only in western developed countries. 1) PNES epidemiology study is of growing interest after ILAE task force publication.2) PNES are found worldwide and sometimes recognized as a cultural phenomenon. 3) New studies are warranted to improve PNES epidemiology knowledge worldwide.