Adult Autism Subthreshold spectrum correlates to Post-traumatic Stress Disorder spectrum in patients with fibromyalgia.

Fibromyalgia (FM) is an increasingly prevalent disorder that usually shows a chronic course and a disappointing therapeutic response in which psychiatric features seem to play a relevant role. Most recently, the relationship between FM and Post-traumatic Stress Disorder (PTSD) has gained interest since several studies demonstrated a higher rate of PTSD, both full blown and partial, and Post-traumatic Stress spectrum symptoms. While the relationship between higher burden of autistic symptoms and PTSD is reported in literature, the relationship between FM and autism spectrum symptoms is still unexplored. In this study we investigated both post-traumatic and autistic spectrum in a sample of FM patients with the aim of exploring the relationships between these dimensions. One hundred and nineteen patients with FM, diagnosed according the American College of Rheumatology 2010 criteria, were consecutively enrolled at the Unit of Rheumatology, University of Pisa, Italy. Assessments included: the Trauma And Loss Spectrum-Self Report (TALS-SR), for the post-traumatic stress spectrum symptomatology, the Adult Autism Subthreshold spectrum (AdAS spectrum) for the assessment of subthreshold autism spectrum. The scores reported to AdAS (total and per domain) by the entire sample and subgroups with PTSD diagnosis, partial PTSD and no PTSD were compared in order to detect a relation between Autistic Traits (ATs) and post-traumatic spectrum in this clinical sample. Our results show that FM patients with PTSD report an AdAS total score significantly higher than those reported by patients without PTSD. Moreover, through an examination of the correlation between AdAS spectrum and TALS-SR scores, significant correlations between the total score of the two instruments has emerged. The correlation resulted to be particularly significant between TALS-SR scores and non-verbal communication domain of the AdAS and between hyper-hypo reactivity to sensory input domain and several TALS-SR domains. These results highlight the clinical relevance of autistic traits in FM patients with PTSD. In this regard, we may claim a potential role of abnormal processing of sensory input and deficits in non-verbal communication in explaining this association.