36 Study of the prevalence of autistic traits and alexithymia, with associated psychiatric comorbidity, in an outpatient program of patients with functional neurological symptom disorder (FNSD)
Authors: Cole Richard , Elmalem Michael , Abrol Esha , Petrochilos Panayiota 
Published: December 2022

Introduction

Whilst higher rates of alexithymia have previously been reported in FNSD, little is known about the prevalence of autistic traits in adults with FNSD. We aim to:

Report on the prevalence of autistic traits in an outpatient group of adults diagnosed with FNSD using the Autism Spectrum Quotient (AQ-10)

Report on the prevalence of alexithymia using the Toronto Alexithymia Scale (TAS-20)

Report on differences in symptom severity of psychiatric comorbidity between those scoring <6 or ≥6 on the AQ-10, and those with or without alexithymia

Method

Out of 105 consecutive patients reviewed in an outpatient FNSD program, 91 completed self-report assessments for autistic traits, alexithymia, generalised anxiety, depression, social phobia, somatic symptom severity, attention deficit hyperactivity disorder (ADHD) and dyslexia. Patients were grouped by AQ-10 scores of <6 or ≥6 and compared for significant differences in tested variables using a Mann-Whitney U test. Kruskal-Wallis H tested differences in alexithymia status. Simple effects were tested using pairwise comparisons.

Results

40% screened positive on the AQ-10 (scoring ≥6), and 40% screen positive for alexithymia. When comparing those scoring < or ≥6 on the AQ-10, those with the higher number of autistic traits scored significantly higher on scales of alexithymia, depression, generalised anxiety, social phobia,ADHD, and dyslexia. Positive alexithymia status was significantly associated with a higher number of autistic traits as well symptoms of generalised anxiety, depression, somatic symptoms severity, social phobia and dyslexia.

Conclusion

Whilst higher rates of neurodevelopmental disorders have previously been reported in FNSD, we report new evidence for a high proportion of autistic traits and further evidence of a high prevalence of alexithymia in a group of adults with FNSD.1–10Mechanistic insights are limited however autistic traits may be associated with FNSD due to altered sensitivity to sensory data, as well as cognitive or affective biases, or increased susceptibility to panic. There may be an additional contribution from psychosocial stressors. Clinically, the AQ-10 and TAS-20 may be important tools in the management of FNSD, and a higher prevalence of autistic traits may highlight a need for specialised communication styles in the MDT.11

This builds on research exploring the relationship between autistic traits, alexithymia and FNSD. Previous research suggests that alexithymia and altered interoceptive awareness may be modifying factors in the relationship between autistic traits and FNSD,12and further research is required to clarify the nature of these relationships.

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