Abstracts

Rationale: In addition to conversion disorder, youth with psychogenic nonepileptic seizures (PNES) have more prevalent psychiatric comorbidities, including internalizing (anxiety, depression) and post-traumatic stress disorders (PTSD), somatization, and anxiety sensitivity (AS), than siblings (AS) (1). Given the difficulties diagnosing the conversion and comorbid psychiatric disorders of pediatric PNES, this national multisite study compared the risk factors for psychiatric comorbidities in PNES youth and their siblings.Methods: The study included 55 PNES youth and 35 siblings, aged 8-18 years. A video EEG confirmed a PNES diagnosis. Parents provided information on the children’s demographic, medical, psychiatric, educational history. Each child and parent underwent a structured psychiatric interview about the child that yielded DSM-IV diagnoses and information on adversities. Each child completed somatization and AS questionnaires, and received cognitive, language, and achievement testing. Probands and siblings were compared on outcome measures using ANCOVAs (controlling for age) and Fisher’s exact tests. Associations of continuous measures (number of internalizing diagnoses (IntDx), somatization and AS scores) within the PNES and sibling groups were examined using general linear models and associations of categorical measures (presence of IntDx, depression and PTSD) were examined using logistic regressions. We examined the profile of correlates of depression and PTSD only in the PNES group because anxiety disorders were present in 83.6% of probands, and only 2.9% and 14.3% siblings had PTSD and depression, respectively.Results: Table 1 presents the number of probands and siblings with internalizing disorders and PTSD, and their somatization and AS scores. The number of proband IntDx was significantly related to female gender (p=.03) and older age of PNES onset (p=.04). In the siblings, it was associated with female gender (p=.04), more adversities (p=.04), and higher somatization scores (p=.02). Higher proband somatization scores were associated with older age (p=.03) and epilepsy (p=.01). In the siblings, they were related to being bullied (p<.0001). Significantly higher proband AS scores were found in females (p=.002) and in those who experienced more adversities (p=.02). But, the siblings AS scores were unrelated to any risk variables. Whereas proband PTSD was significantly associated with female gender and lower Full Scale IQ, depression was unrelated to the risk variables studied.Conclusions: The risk factor profile of internalizing disorders in the siblings (female, adversities, bullying, somatization) is similar to that of youth in the general population. A distinct risk factor profile (female, older age, epilepsy, adversities, lower IQ) characterizes the more prevalent comorbid psychopathology of PNES youth. This finding might play a role in the difficulty diagnosing internalizing disorders and PTSD in PNES youth particularly when cognitive problems are present.