Psychiatric and neurologic predictors of psychogenic pseudoseizure outcome

Abstract

OBJECTIVE: To investigate the patterns of occurrence of psychogenic pseudoseizures (PPS) of 45 consecutive patients during a 6-month period after diagnosis, and to determine whether psychiatric and neurologic variables identified previously in PPS patient series can predict their recurrence after diagnosis, and whether any of these variables are associated with a particular outcome pattern. METHOD: Postdiagnosis PPS recurrence was assessed twice: during the first month and during a period ranging from the second to the sixth month. Outcome was categorized as follows: class I, complete cessation of PPS; class II, PPS only during one of the two observation periods; and class III, persistent PPS during the two observation periods. The authors used a logistic regression model to identify predictors of PPS recurrence (versus no PPS) among four neurologic and nine psychiatric variables, and compared their frequency among the three outcome classes. RESULTS: Class I, n = 13 (29%); class II, n = 12 (27%); and class III, n = 20 (44%). The presence of an abnormal MR image predicted PPS recurrence during the second observation period with a 75% accuracy. The presence of all nine psychiatric variables predicted PPS recurrence during both the first and second observation periods with a 93% and an 89% accuracy respectively. Patients with a class III outcome had a markedly higher frequency of recurrent major depression, dissociative and personality disorders, and a history of chronic abuse. Patients with a class II outcome displayed a notably higher frequency of denial of stressors and psychosocial problems, refusal of treatment recommendations, and new somatic symptoms after disclosure of diagnosis. Conversely, one episode of major depression was the one common diagnosis in patients with a class I outcome. CONCLUSIONS: PPS outcome after disclosure of diagnosis can be predicted by the presence of certain psychiatric characteristics. More than one psychopathogenic mechanism appears to operate in PPS.