Functional neurological disorder is a feminist issue

Functional neurological disorder (FND) is a common and disabling disorder, often misunderstood by clinicians. Although viewed sceptically by some, FND is a diagnosis that can be made accurately, based on positive clinical signs, with clinical features that have remained stable for over 100 years. Despite some progress in the last decade, people with FND continue to suffer subtle and overt forms of discrimination by clinicians, researchers and the public. There is abundant evidence that disorders perceived as primarily affecting women are neglected in healthcare and medical research, and the course of FND mirrors this neglect. We outline the reasons why FND is a feminist issue, incorporating historical and contemporary clinical, research and social perspectives. We call for parity for FND in medical education, research and clinical service development so that people affected by FND can receive the care they need.

Functional neurological disorder in people with long COVID: A systematic review

BACKGROUND AND PURPOSE

Acute health events, including infections, can trigger the onset of functional neurological disorder (FND). It was hypothesized that a proportion of people with long COVID might be experiencing functional symptoms.

METHODS

A systematic review of studies containing original data on long COVID was performed. The frequency and characteristics of neurological symptoms were reviewed, looking for positive evidence suggesting an underlying functional disorder and the hypothesized causes of long COVID.

RESULTS

In all, 102 studies were included in our narrative synthesis. The most consistently reported neurological symptoms were cognitive difficulties, headaches, pain, dizziness, fatigue, sleep-related symptoms and ageusia/anosmia. Overall, no evidence was found that any authors had systematically looked for positive features of FND. An exception was three studies describing temporal inconsistency. In general, the neurological symptoms were insufficiently characterized to support or refute a diagnosis of FND. Moreover, only 13 studies specifically focused on long COVID after mild infection, where the impact of confounders from the general effects of severe illness would be mitigated. Only one study hypothesized that some people with long COVID might have a functional disorder, and another eight studies a chronic-fatigue-syndrome-like response.

DISCUSSION

Neurological symptoms are prevalent in long COVID, but poorly characterized. The similarities between some manifestations of long COVID and functional disorders triggered by acute illnesses are striking. Unfortunately, the current literature is plagued by confounders, including the mixing of patients with initial mild infection with those with severe acute medical complications. The hypothesis that long COVID might in part correspond to a functional disorder remains untested.

Prognosis of functional neurologic disorders

The prognosis of functional (psychogenic) neurologic disorders is important in being able to help answer patients' and carers' questions, determine whether treatment is worthwhile, and to find out which factors predict outcome. We reviewed data on prognosis of functional neurologic disorders from two systematic reviews on functional motor disorders and dissociative (nonepileptic) seizures as well as additional studies on functional visual and sensory symptoms. Methodologic problems include heterogeneity in studied samples and outcome measures, diagnostic suspicion and referral bias, small size and retrospective design of available studies, possible treatments during follow-up, and literature review bias. With these caveats, the prognosis of functional neurologic disorders does appear to be generally unfavorable. In most studies, functional motor symptoms and psychogenic nonepileptic attacks remain the same or are worse in the majority of patients at follow-up. Measures of quality of life and working status were often poor at follow-up. Frequency of misdiagnosis at follow-up was as low as other neurologic and psychiatric disorders. Long duration of symptoms was the most distinct negative predictor. Early diagnosis and young age seem to predict good outcome. Emotional disorders and personality disorders were inconsistent predictors. Litigation and state benefits were found to be negative predictors in some studies, but others found they did not influence outcome.

The prognosis of functional (psychogenic) motor symptoms: a systematic review

BACKGROUND

The prognosis of functional (or psychogenic) motor symptoms (weakness and movement disorder) has not been systematically reviewed.

METHODS

We systematically reviewed PubMed for all studies of eight or more patients with functional motor symptoms reporting follow-up data longer than 6 months (excluding studies reporting specific treatments). We recorded symptom duration, physical and psychiatric comorbidity, disability, occupational functioning at follow-up and prognostic factors.

RESULTS

24 studies were included. There was heterogeneity regarding study size (number of patients (n)=10 491), follow-up duration clinical setting and data availability. Most studies (n=15) were retrospective. Reported symptom outcome was highly variable. Mean weighted follow-up duration was 7.4 years (in 13 studies where data was extractable). The mean percentage of patients same or worse at follow-up for all studies was 39%, range 10% to 90%, n=1134. Levels of physical disability and psychological comorbidity at follow-up were high. Short duration of symptoms, early diagnosis and high satisfaction with care predicted positive outcome in two studies. Gender had no effect. Delayed diagnosis and personality disorder were negatively correlated with outcome. Prognostic factors that varied between studies included age, comorbid anxiety and depression, IQ, educational status, marital status and pending litigation.

CONCLUSIONS

Existing follow-up studies of functional motor symptoms give us some insights regarding outcome and prognostic factors but are limited by their largely retrospective and selective nature. Overall, prognosis appears unfavourable. The severity and chronicity of functional motor symptoms argues for larger prospective studies including multiple prognostic factors at baseline in order to better understand their natural history.