Prospective multicenter cohort study of possible psychogenic nonepileptic seizure cases—Results at 1‐year follow‐up examinations

OBJECTIVE: The primary purpose of this prospective multicenter study was to examine clinical and demographic feature differences according to the diagnostic level of psychogenic nonepileptic seizures (PNES) and then clarify whether prognosis may also differ accordingly. METHODS: Two hundred forty‐two consecutive patients strongly suspected of having PNES attacks were invited to participate, of whom 52 did not consent or contact was lost. At the 1‐year follow‐up examination, PNES diagnosis was reconsidered in nine patients. In 96 patients, the diagnostic level remained the same (P‐group), with that in 43 considered to be clinically established (CE‐group) and in 42 documented (D‐group). The Qolie‐10 and NDDI‐E questionnaires were examined at both the study entry and the follow‐up examination. RESULTS: Multiple regression analysis of quality of life (QoL) score (n = 173; R (2) = 0.374; F = 7.349; P < 0.001) revealed NDDI‐E score (t = −6.402; P < 0.001), age of PNES onset (t = −3.026; P = 0.003), and ethnic minority status (t = 3.068; P = 0.003) as significant contributors. At entry, the P‐group showed the lowest PNES attack frequency (P < 0.000), the lowest rate of antiseizure, antidepressant, and antipsychotic medication (P < 0.000; P = 0.031; P = 0.013, respectively), and the lowest proportion of psychosis (P = 0.046). At follow‐up, PNES attack frequency (P < 0.000), number of admittances to emergency room (P < 0.000), and scores for QoL (P < 0.000) as well as depression (P = 0.004) were found to be significantly improved together with other collateral indicators, such as rate of antiseizure medication prescription (P = 0.001) and psychiatric symptoms (P = 0.03). Multiple regression analysis of a sample limited to patients with intellectual disability (ID) (n = 44; R (2) = 0.366; F = 4.493; P = 0.002) revealed continued psychotherapy at follow‐up (t = 2.610, P = 0.013) and successful reduction in antiseizure medication (t = 2.868; P = 0.007) as positively related with improved QoL. SIGNIFICANCE: Clinical and the socio‐psychological constellation of possible, clinically established, and documented PNES were found to differ greatly. Unexpectedly, significant effects of the continuous psychotherapeutic intervention were confirmed in PNES patients with ID.