Mortality in patients with psychogenic non-epileptic seizures

<p><span><b>Objective</b></span></p> <p><span>To investigate the hypothesis that patients diagnosed with PNES on video-EEG monitoring (VEM) have increased mortality by comparison to the general population. </span></p> <p> </p> <p><span><b>Methods</b></span></p> <p><span><span>This retrospective cohort study included patients evaluated in VEM units of three tertiary hospitals in Melbourne, Australia, between January 1^st, 1995 and December 31^st, 2015. Diagnosis was based on consensus opinion of experienced epileptologists and neuropsychiatrists at each hospital. </span>Mortality was determined <span>in patients diagnosed with PNES, epilepsy or both conditions,</span> by linkage to the Australian National Death Index (NDI)<span>. Lifetime history of psychiatric disorders in PNES was determined from formal neuropsychiatric reports. </span></span></p> <p> </p> <p><span><b>Results </b></span></p> <p><span>5,508 patients underwent VEM. 674 (12.2%) were diagnosed with PNES, 3064 (55.6%) with epilepsy, 175 (3.2%) with both conditions, and 1,595 (29.0%) received other diagnoses or had no diagnosis made. The standardised mortality ratio (SMR) of patients diagnosed with PNES was 2.5 (95% CI 2.0–3.3). Those younger than 30 years had an 8-fold higher risk of death (95% CI 3.4–19.8). Direct comparison revealed no significant difference in mortality rate between diagnostic groups. Amongst deaths in patients diagnosed with PNES (n=55), external causes contributed 18%, with 20% of deaths in those younger than 50 years attributed to suicide, and "epilepsy" was recorded as the cause of death in 24%.  </span></p> <p> </p> <p><span><b>Conclusions </b></span></p> <p><span><span>Patients diagnosed with PNES have a SMR 2.5 times above the general population, dying at a rate comparable to those with drug-resistant epilepsy. This emphasises the importance of prompt diagnosis, identification of risk factors, and the implementation of appropriate strategies to prevent potential avoidable deaths.</span></span></p>