Diagnostic accuracy of clinical signs and symptoms for psychogenic nonepileptic attacks versus epileptic seizures..., 2021, Gilmour et al

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

Highlights

• Systematic review comparing psychogenic nonepileptic attacks and epileptic seizures.
• Individual clinical features carry limited distinguishing certainty.
• History of sexual abuse had highest specificity for psychogenic nonepileptic attacks.
• Female sex had highest sensitivity for psychogenic nonepileptic attacks.
• Need for creation of multisource predictive tools to optimize likelihood ratios.

Abstract
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.

Paywall, https://www.epilepsybehavior.com/article/S1525-5050(21)00264-X/fulltext

 

If it was as simple as "not caused by abnormal electrical cortical activity" surely there would be no need for any other criteria?

Being female and having been sexually abused could be the best indicators because people in those categories are more likely to be diagnosed with it.

Pooling lots of bad studies does not add any credibility to the diagnosis.

 

Aren't predominantly female and a higher rate of sexual abuse two sides of the same coin? The real rates of sexual abuse are significantly higher than most people understand, even clinical psychologists, so any demographic with a predominantly female population will have higher rates of sexual abuse than a general population split 50:50, especially in a setting that is more intrusive in getting real answers, many abused never report it anywhere, but they may in a medical setting. Sounds about as useful as hair length, which would correlate about the same way.

But anyway this is completely pointless, they are comparing unreliable guesstimates to other unreliable guesstimates, which is about as accurate as asking different people to estimate something. Using other estimates to validate one additional estimate is really not useful when you are required to have precision. You know, the whole point of science, of not guessing but actually verifying. At some point there is supposed to be a comparison that relates to real things, without this it's all just eyeballing with a few extra steps.

Then of course if one uses a history of sexual abuse to diagnose this, like Mithriel said, you will naturally find more diagnosed with a history of sexual abuse. Bit like using a population of roller-coaster riders and finding they are taller than average, or that military recruits have exactly two arms on average. I mean yeah it's literally an admission criterion. SMH.

And the fact that this is commonly used in practice without there being any validity to it should be raising all the damn questions about ethics, but this is all too easy not to know about if nobody is allowed to ask the questions.

 

Thinking about it, "female" and "sexual abuse" are not specific enough to use for a diagnosis. There is no path offered by which being female can cause a seizure. It harks back to women having weaker brains and constitutions and is no more medical than that.

Then "a history of sexual abuse", what exactly does that mean for health? The term is a broad one used in criminal and sociological contexts but the abuse covers everything from violent rape to being flashed in the playground. Now they may mean that the trauma causes continuing mental health issues but then why should sexual trauma be worse than any other? Being groped on a bus compared to seeing a parent murdered, which one causes seizures and why?

For a diagnosis which is based on symptoms not being "congruent" their alternative to physical disease are wildly unlikely.