Psychogenic Nonepileptic Seizures (PNES): Comprehensive Clinical Overview
Etiology and Pathophysiology
Psychogenic nonepileptic seizures represent a conversion disorder—an involuntary external somatic manifestation of internal psychological stresses—and should not be confused with malingering. 1
Underlying Mechanisms
The etiology is heterogeneous and multifactorial, involving several interacting components:
Psychological trauma: Exposure to traumatic events is common but not universal in PNES patients, with elevated rates of physical and/or sexual abuse history, particularly in young females 1, 2
Dissociative mechanisms: Trait dissociation is frequently present but not inevitable; there is a characteristic mismatch between subjective anxiety reports and actual physical arousal during episodes 2
Psychiatric comorbidities: Elevated physical symptom reporting, somatization patterns, and preexisting psychiatric conditions (depression, anxiety) are consistently identified 2
Vulnerability factors: Include insecure attachment patterns, emotion regulation difficulties, alexithymia, and maladaptive coping mechanisms 2
Perpetuating factors: Symptom modeling, learned behaviors, family/relationship dysfunction, and secondary gain mechanisms contribute to chronicity 3, 2
Importantly, PNES occurs in the absence of impaired cerebral perfusion or abnormal cortical electrical activity, distinguishing it fundamentally from epileptic seizures. 1
Diagnostic Features
Clinical Characteristics That Suggest PNES
Video-EEG monitoring remains the gold standard for diagnosis, demonstrating normal EEG activity during episodes with preserved consciousness. 4
Key clinical features include:
- Eyes closed during unconsciousness (highly suggestive; epileptic seizures typically occur with eyes open) 1, 4
- Pelvic thrusting movements 1, 4
- Eye fluttering 1, 4
- Waxing and waning intensity with changes in movement patterns (repeated fluctuations in nature and intensity) 1, 4
- Prolonged duration of loss of consciousness (>5 minutes suggests PNES rather than syncope; mean duration ~90 seconds vs. brief syncope) 1
- Out-of-phase limb movements (though less frequent than historically believed) 5
- Slow, subtle writhing or in-phase limb movements (can be mistaken for status epilepticus) 5
Distinguishing from Epileptic Seizures
- Normal pulse, blood pressure, and EEG during episodes can be documented 1
- Absence of postictal confusion (patients often return to baseline quickly) 1
- Variability in clinical presentations across different episodes 1
- Distractibility and suggestibility during episodes 1
- Adult age of onset (more common in PNES than new-onset epilepsy) 1
Diagnostic Pitfalls
A critical caveat: 74% of PNES patients receive inappropriate anticonvulsant therapy, and some are aggressively treated for presumed status epilepticus based solely on observation without proper neurologic examination. 5 This represents a major diagnostic and therapeutic error with significant morbidity implications.
Treatment Plan
Initial Intervention: Diagnosis Communication
The necessary first step is explaining the diagnosis with care in a clear but sympathetic manner that acknowledges the involuntary nature of the attacks. 1, 3
- A candid discussion about the diagnosis may be reasonable (Class IIb recommendation) 1
- Psychoeducational programs about the condition can improve quality of life and seizure management 4, 6
- Emphasize that PNES is a real medical condition, not "faking" or malingering 3, 7
Primary Treatment Modality
Cognitive Behavioral Therapy (CBT) represents the preferred treatment for most PNES patients, though evidence shows only a non-statistically significant trend toward improvement. 1
Specific psychotherapeutic interventions include:
- CBT principles as the foundation 4, 6
- Relaxation therapy techniques 4, 6
- Psychoeducational programs 4, 6
- Family counseling 4
- Individualized psychological assessment to tailor interventions to underlying factors 6, 3
Multidisciplinary Approach
A holistic approach involving multiple specialists yields better outcomes than single-provider management. 4
The team should include:
- Neurologist to confirm diagnosis and exclude epilepsy 4
- Primary care physician to coordinate care 4
- Mental health professional (psychologist/psychiatrist) for psychotherapy 8, 7
- Other specialists as needed for comorbid conditions 4
Pharmacotherapy
There are no data supporting significant benefit from pharmacotherapy for PNES itself. 1 However, treatment of comorbid psychiatric conditions (depression, anxiety) may be appropriate using standard psychiatric medications.
Special Populations
For patients with intellectual disabilities, treatment should be adapted to cognitive level using modified approaches with gesture, prosody, and simplified psychoeducational programs 6
Prognosis and Outcomes
Short-Term Outcomes
No specific 30-day survival rate data exists for PNES because mortality from PNES episodes themselves is essentially zero—these are not life-threatening events in the acute sense. The concept of "30-day survival" is not applicable to PNES as it would be for conditions like stroke or myocardial infarction.
Long-Term Prognosis
Studies consistently report that one-third to one-quarter of PNES patients become chronic despite treatment. 3
Outcome measures should prioritize:
- Quality of life improvements (often more important than seizure frequency alone) 6, 8
- Seizure frequency and severity reduction 3, 8
- Functional status and disability measures 7
- Reduction in healthcare utilization 7
Prognostic Factors
- Seizure freedom may not be achieved in all patients, but quality of life can still improve with treatment 8
- Refractory cases exist and require additional treatment modalities and further research 8
- Early diagnosis and intervention likely improve outcomes, though specific data are limited 3, 7
Morbidity Considerations
The primary morbidity from PNES includes:
- Iatrogenic harm from inappropriate anticonvulsant therapy (74% receive unnecessary medications) 5
- Aggressive treatment for misdiagnosed status epilepticus with associated medication risks 5
- Significant functional disability and reduced quality of life 7
- Psychological distress and psychiatric comorbidity burden 7, 2
- Healthcare resource overutilization and associated costs 7
The heterogeneity of PNES patients means treatment must be individualized based on underlying psychological mechanisms, but CBT-based approaches with multidisciplinary support represent the current evidence-based standard. 3, 8, 2