Are Patients with Psychogenic Movement Disorders More Likely to be Healthcare Workers?

Healthcare employment as a risk factor for functional neurological disorder: A case-control study

BACKGROUND AND PURPOSE

Female gender, younger age and stressful life events are known predisposing factors for functional neurological disorders (FNDs). Employment in a healthcare profession has also been suggested to be a predisposing factor. We set out to conduct a large-scale case-control study to estimate the rate employment in a healthcare profession among people with FND.

METHODS

We included 200 consecutive patients with a confirmed diagnosis of FND, referred to our clinic at University Hospital Bern Switzerland between October 1, 2016, and August 1, 2019. In addition, we included a control group of 200 patients with a confirmed neurological disorder, matched for age and gender, seen during the same period. The primary endpoint was to compare the prevalence of healthcare professionals between the groups. We also describe the clinical manifestations and concomitant psychiatric diagnoses in the FND cohort.

RESULTS

Female gender was predominant (70%), and the participants' mean age was 37 years. The proportion of healthcare professionals in the FND patients was 18% (33/186), which was significantly higher than in the control group, in which it was 10.6% (17/189; p = 0.019, 95% confidence interval odds ratio 1.168-4.074). Most healthcare professionals in both cohorts were nurses (21/33 among FND patients, 10/17 among controls). Among FND patients, 140 (70%) had motor symptoms and 65 (32.5%) had a concomitant psychiatric diagnosis.

CONCLUSION

This case-control study confirmed a higher rate of employment in healthcare professions in patients with FND, suggesting two potential mechanisms of FND: exposure to models/specific knowledge about neurological symptoms or stress-related professional factors. This warrants further studies on underlying mechanisms and prevention.

Predisposing Risk Factors for Functional Limb Weakness: A Case-Control Study

OBJECTIVE

Functional limb weakness is a common symptom of functional neurological disorder. Few controlled studies have examined possible predisposing factors to determine their specificity for this symptom.

METHODS

In this prospective case-control study, patients with functional limb weakness (<2 years duration, N=107) were compared with a control group (comprising patients with weakness attributable to neurological disease, N=46, and healthy individuals, N=39). A structured clinical interview and questionnaires assessed potential predisposing factors, including family structure and childhood abuse and neglect (Childhood Trauma Questionnaire [CTQ]), personality traits (NEO Five-Factor Inventory), medical and surgical comorbidity, and exposure to a symptom model.

RESULTS

The patients with functional limb weakness and the control subjects were similar in gender and age. Self-reported childhood sexual abuse (15% versus 5%, p<0.01), and physical abuse (18% versus 7%, p<0.01; CTQ "moderate or above") were more common in the functional limb weakness group, although the absolute frequency was lower than anticipated. In the functional limb weakness group, there were modest differences in two personality traits, compared with the control group: higher neuroticism (p=0.02) and lower openness (p=0.01). Medical comorbidity, including appendectomy (33% versus 5%), irritable bowel syndrome (36% versus 18%), and chronic back pain (40% versus 16%), was more frequent in the functional limb weakness group. There were no differences in birth order or exposure to a symptom model.

CONCLUSIONS

Medical and surgical comorbidity and adverse childhood experience are risk factors, but not essential, for the development of functional limb weakness. However, evidence for personality traits or exposure to a symptom model is less robust.

Clinical Correlates of Functional Motor Disorders: An Italian Multicenter Study

Background

Functional motor disorders (FMDs) are abnormal movements that are significantly altered by distractive maneuvers and are incongruent with movement disorders seen in typical neurological diseases.

Objective

The objectives of this article are to (1) describe the clinical manifestations of FMDs, including nonmotor symptoms and occurrence of other functional neurological disorders (FND); and (2) to report the frequency of isolated and combined FMDs and their relationship with demographic and clinical variables.

Methods

For this multicenter, observational study, we enrolled consecutive outpatients with a definite diagnosis of FMDs attending 25 tertiary movement disorders centers in Italy. Each patient underwent a detailed clinical evaluation with a definition of the phenotype and number of FMDs (isolated, combined) and an assessment of associated neurological and psychiatric symptoms.

Results

Of 410 FMDs (71% females; mean age, 47 ± 16.1 years) the most common phenotypes were weakness and tremor. People with FMDs had higher educational levels than the general population and frequent nonmotor symptoms, especially anxiety, fatigue, and pain. Almost half of the patients with FMDs had other FNDs, such as sensory symptoms, nonepileptic seizures, and visual symptoms. Patients with combined FMDs showed a higher burden of nonmotor symptoms and more frequent FNDs. Multivariate regression analysis showed that a diagnosis of combined FMDs was more likely to be delivered by a movement disorders neurologist. Also, FMD duration, pain, insomnia, diagnosis of somatoform disease, and treatment with antipsychotics were all significantly associated with combined FMDs.

Conclusions

Our findings highlight the need for multidimensional assessments in patients with FMDs given the high frequency of nonmotor symptoms and other FNDs, especially in patients with combined FMDs.

Characteristics of patients with motor functional neurological disorder in a large UK mental health service: a case-control study

BACKGROUND

Functional neurological disorder (FND), previously known as conversion disorder, is common and often results in substantial distress and disability. Previous research lacks large sample sizes and clinical surveys are most commonly derived from neurological settings, limiting our understanding of the disorder and its associations in other contexts. We sought to address this by analysing a large anonymised electronic psychiatric health record dataset.

METHODS

Data were obtained from 322 patients in the South London and Maudsley NHS Foundation Trust (SLaM) who had an ICD-10 diagnosis of motor FND (mFND) (limb weakness or disorders of movement or gait) between 1 January 2006 and 31 December 2016. Data were collected on a range of socio-demographic and clinical factors and compared to 644 psychiatric control patients from the same register.

RESULTS

Weakness was the most commonly occurring functional symptom. mFND patients were more likely to be female, British, married, employed pre-morbidly, to have a carer and a physical health condition, but less likely to have had an inpatient psychiatric admission or to receive benefits. No differences in self-reported sexual or physical abuse rates were observed between groups, although mFND patients were more likely to experience life events linked to inter-personal difficulties.

CONCLUSIONS

mFND patients have distinct demographic characteristics compared with psychiatric controls. Experiences of abuse appear to be equally prevalent across psychiatric patient groups. This study establishes the socio-demographic and life experience profile of this understudied patient group and may be used to guide future therapeutic interventions designed specifically for mFND.