Functional neurological disorder is common in patients attending chronic pain clinics 2023 Mason, McWhirter, Carson, Stone et al

Background

Chronic pain is a common comorbidity in those with functional neurological disorder (FND), however the prevalence and characteristics of FND in those with chronic pain is unknown.

Methods
A retrospective electronic records review of consecutive new patients attending a chronic pain clinic of a regional service. Clinical features, medication and outcome of chronic pain, any lifetime diagnoses of functional, FND and psychiatric disorders and undiagnosed neurological symptoms were recorded.

Results
Of 190 patients attending the chronic pain clinic, 32 (17%) had a lifetime diagnosis of FND and an additional 11 (6%) had undiagnosed neurological symptoms. Pain patients with comorbid FND were more likely to have chronic primary pain (88% with FND, 44% without FND, p < 0.0001), widespread chronic primary pain (53%, 15%, p < 0.00001) and depression (84%, 52%, p < 0.005) and less likely to have a pain-precipitating event (19% vs 56%, p < 0.001). However, there was no significant difference between these patients in opiate prescription, benzodiazepine prescription or pain outcome.

Conclusions
This first study of FND in a chronic pain patient population found a remarkably high prevalence of FND (17%) and is possibly an underestimate. The size of the overlap indicates that FND and chronic pain research fields are likely to have a lot to learn from each other.

Paywall, https://onlinelibrary.wiley.com/doi/10.1111/ene.15892

 

They're probably using an extremely vague definition of FND to reach that conclusion, just like how BPS researchers use extremely vague definitions of ME. Real FND requires very careful evaluation. Their definition is probably "we found the most ableist neurologist we could, and he opined 1/6 of people with chronic pain had FND."

 

Since FND is so poorly defined, you can probably equally validly claim that "FND is common in patients who <watch reality TV, put ketchup on waffles, pretty much anything anyone does>".

 

->

The median time elapsing between the onset of chronic pain and the onset of FND was 5 years (range 0-22 years).
The median time elapsing between the onset of FND and chronic pain was 4 years (range 0-27 years).

 

Stone’s neurobabble website says that symptoms like tingling and fatigue etc are FND. Basically, any symptom imaginable experienced by nearly everyone.

 

That's how you know it's super common!

 

Chronic pain clinics are designed to manage people with chronic pain for which no cause can be found - i.e., in Stone's terminology functional pain.

Pain is neurological.

So ALL the patients should have this 'functional neurological disorder'. Why could they only find 17%? Seems they aren't that hot at making a diagnosis.

Looked at another way, since we should expect MUCH higher rates of FND in these clinics than in routine clinics doesn't this suggest that figures banded about for routine clinics are a bit exaggerated? @dave30th

 

Only 17% had Hoover's sign or one of the other signs they claim can be used for a positive diagnosis?