Psychogenic nonepileptic seizures: The effect of accurate diagnosis on cognition.

OBJECTIVE

Much remains to be elucidated about the cognitive profile of patients with psychogenic nonepileptic seizures (PNES) and about how this changes over time and compares to that of patients with epilepsy. The aim of this study was to study the neuropsychological profile of patients with PNES and an age-matched group of patients with temporal lobe epilepsy (TLE) during admission to a video electroencephalography monitoring unit (VEMU) and 1 year after discharge.

METHODS

Patients diagnosed with PNES or TLE at a VEMU were prospectively recruited. Neuropsychological, demographic, clinical, and treatment variables were collected at baseline and 1 year. To minimize multiple comparisons, scores from different cognitive tests were computed for attention and psychomotor speed, verbal memory, visual memory, language, and executive function. A global cognitive impairment index (GCII) was also created. Post hoc analyses were conducted to identify clinical variables that might mediate the differences observed in cognition over time between the groups. These included seizure frequency, number of antiseizure medication (ASM), number of psychotropic drugs, depression, and quality of life.

RESULTS

We studied 24 patients with PNES and 24 patients with TLE. The groups performed similarly in the baseline neuropsychological tests. There was a significant time (baseline to 1-year follow-up) by group (PNES vs TLE) interaction for the GCII (p = 0.006), language (p = 0.04), and executive function (p = 0.013), with PNES patients showing improvement and TLE patients remaining stable. The time by group interaction for attention and psychomotor speed showed a trend toward significance (p = 0.056), Reduction in number of ASM was associated with improved cognition in PNES patients at 1 year.

CONCLUSION

PNES patients showed improved cognition at 1 year of follow-up, particularly in language and executive functions. This finding shows the potential benefits of an early, accurate diagnosis, which range from improved cognition to better management.