Characteristics of patients with confirmed epilepsy and psychogenic nonepileptic seizures in Qatar

Psychogenic non-epileptic seizures with and without epilepsy: Exploring the influence of co-existing psychiatric disorders on clinical characteristics and outcomes

BACKGROUND AND OBJECTIVES

Psychogenic non-epileptic seizures (PNES) are commonly associated with co-existing psychiatric disorders. The relationship between psychiatric factors and PNES episodes with and without epilepsy remains understudied. We reviewed co-existing psychiatric disorders in PNES-only, PNES with epilepsy aiming to examine whether these co-existing disorders associated with PNES clinical presentation and long-term outcomes.

METHODS

We conducted a retrospective, longitudinal cohort study of patients with PNES diagnosed at our EMU from May 2000 to April 2008, with follow-up clinical data until September 2015. We categorized patients into three groups: PNES-only, PNES+ definite epilepsy, and PNES+ possible/probable epilepsy.

RESULTS

In total, 271 patients with PNES were identified: 194 had PNES-only, 30 had PNES+ possible or probable epilepsy, and 47 had PNES+ definite epilepsy. No significant differences were observed in the prevalence of depression, anxiety, post-traumatic stress disorder (PTSD), substance abuse, or suicidal thoughts among the three groups. Similarly, no differences in co-existing psychiatric disorders characteristics were discovered among patients grouped by various durations and frequencies of PNES episodes. At EMU admission, for PNES-only patients total of 130/194 patients (67%) were on ASMs, and 64/194 (32.9%) were not. PNES-only not on ASM were the most likely to report at least two of the three main psychiatric disorders (depression, anxiety, and PTSD; p = 0.01). At the final follow-up, 68/130 (52.3%) and 92/130 (70.8%) patients were able to discontinue or reduce their ASM intake, respectively, with no significant differences in co-existing psychiatric disorders among them (p < 0.001). Overall, 51.6% or 31.3% of patients reported reduced or resolved PNES episodes, respectively. Further, this reduction and resolution of PNES episode were not affected by any psychological variable.

CONCLUSIONS

Co-existing psychiatric disorders prevalence did not differ between patients with PNES-only and those with coexisting epilepsy. Further, co-existing psychiatric disorders characteristics did not reliably predict PNES episode duration, frequency, reduction, or resolution. For patients with PNES-only, the presence of co-existing psychiatric disorders did not predict the rate at which ASMs could be reduced or discontinued.

Diagnostic accuracy of clinical signs and symptoms for psychogenic nonepileptic attacks versus epileptic seizures: A systematic review and meta-analysis

BACKGROUND

Psychogenic nonepileptic attacks (PNEA) are events of altered behavior that resemble epileptic seizures (ES) but are not caused by abnormal electrical cortical activity. Understanding which clinical signs and symptoms are associated with PNEA may allow better triaging for video-electroencephalogram monitoring (VEM) and for a more accurate prediction when such testing is unavailable.

METHODS

We performed a systematic review searching Medline, Embase, and Cochrane Central from inception to March 29, 2019. We included original research that reported at least one clinical sign or symptom, included distinct groups of adult ES and PNEA with no overlap, and used VEM for the reference standard. Two authors independently assessed quality of the studies using the Quality Assessment of Diagnostic Accuracy Studies tool. Pooled estimates of sensitivity and specificity of studies were evaluated using a bivariate random effects model.

RESULTS

We identified 4028 articles, of which 33 were included. There was a female sex predominance in the PNEA population (n = 22). From our meta-analysis, pooled sensitivities (0.27-0.72) and specificities (0.51-0.89) for PNEA were modest for individual signs. History of sexual abuse had the highest pooled specificity (89%), while the most sensitive feature was female sex (72%). Individual studies (n = 4) reported high levels of accuracy for ictal eye closure (sensitivity 64-73.7% and specificity 76.9-100%) and post-traumatic stress disorder (no reported sensitivity or specificity). Assuming the pre-test probability for PNEA in a tertiary care epilepsy center is 14%, even the strongest meta-analyzed features only exert modest diagnostic value, increasing post-test probabilities to a maximum of 33%.

CONCLUSIONS

This review reflects the limited certainty afforded by individual clinical features to distinguish between PNEA and ES. Specific demographic and comorbid features, even despite moderately high specificities, impart minimal impact on diagnostic decision making. This emphasizes the need for the development of multisource predictive tools to optimize diagnostic likelihood ratios.