Contents lists available at ScienceDirect Psychiatry Research journal homepage: www.elsevier.com/locate/psychres The mediating effect of trauma and stressor related symptoms and ruminations on the relationship between autistic traits and mood spectrum Liliana Dell'Osso a , Barbara Carpita a, ⁎ , Ivan Mirko Cremone a , Dario Muti a , Elisa Diadema a , Filippo Maria Barberi a , Gabriele Massimetti a , Natascia Brondino b , Beatrice Petrosino c , Pierluigi Politi b , Eugenio Aguglia c , Primo Lorenzi d , Claudia Carmassi a , Camilla Gesi a a Department of Clinical and Experimental Medicine, University of Pisa, Italy b Department of Brain and Behavioral Sciences, University of Pavia, via Bassi 21, Pavia 27100, Italy c Department of Clinical and Experimental Medicine, Psychiatry Unit, University of Catania, Catania, Italy d Clinical Psychology and Psychotherapy, University of Florence, Careggi Hospital, Florence, Italy ARTICLE INFO Keywords: Autism spectrum Mood spectrum Ruminations Stressor related symptoms Trauma ABSTRACT An increasing number of studies highlighted significant correlations between autistic traits (AT) and mood spectrum symptoms. Moreover, recent data showed that individuals with high AT are likely to develop trauma and stressor-related disorders. This study aims to investigate the relationship between AT and mood symptoms among university students, focusing in particular on how AT interact with ruminations and trauma-related symptomatology in predicting mood symptoms. 178 students from three Italian Universities of excellence were assessed with The Structured Clinical Interview for DSM-5 (SCID-5), the Adult Autism Subthreshold Spectrum (AdAS Spectrum), the Ruminative Response Scale (RRS), the Trauma and Loss Spectrum (TALS) and the Moods Spectrum (MOODS). Considering the AdAS Spectrum total scores, 133 subjects (74.7%) were categorized as “low scorers” and 45 subjects (25.3%) as “high scorers”. Students in the high scorer group showed significantly higher scores on RRS, TALS-SR and MOOD-SR total scores. Total and direct effects of AdAS Spectrum total score on MOODS-SR total score were both statistically significant. AdAS Spectrum total score also showed a significant indirect effect on MOODS-SR total score through TALS and RRS total scores. Results showed a significant re- lationship between AT and mood spectrum, which is partially mediated by ruminations and trauma/stressor- related symptomatology. 1. Introduction The Broad Autism Phenotype (Billeci et al., 2016; Dell'Osso et al., 2016a, b; Losh et al., 2009; Losh et al., 2008; Taylor et al., 2017) has been conceptualized to describe milder manifestations of autism, such as impaired social and communication skills, unusual aloof personality, repetitive and stereotyped behaviors, frequently found among un- affected relatives of people with Autism Spectrum Disorder (ASD). Parallel, subthreshold manifestations of autism have been shown to be variously distributed in some high risk groups from the general popu- lations (Choteau et al., 2016; Dell'Osso et al., 2017; Skylark and Baron- Cohen, 2017; Suzuki et al., 2017), as well as highly prevalent in a broad variety of clinical groups, including patients with eating disorders, major depression, suicidal behavior, borderline personality disorder (Dell'Osso et al., 2018a, b, 2015a; Takara and Kondo, 2014a; Tchanturia et al., 2013), where they are usually referred to as autistic traits (AT). The specific interest in exploring AT lies in the fact that they seem to interfere with overall functioning, and they may be, according to a growing number of studies, a significant risk factor for developing clinical symptoms, as well as suicidal ideation (Dell'Osso et al., 2016a, b). While the role of AT in affecting the development of personality has been long debated in literature (Anckarsäter et al., 2006), several data suggest that they may also represent a vulnerability factor for devel- oping many other disorders. In particular, robust data highlight a sig- nificant correlation between AT and mood disorders (Kanne et al., 2009; Kunihira et al., 2006; Liu et al., 2017; Matsuo et al., 2015; Pine et al., 2008; Towbin et al., 2005) which is also consistent with findings about the clinical forms of ASD, that show a high prevalence of de- pressive disorders among ASD patients (Hofvander et al., 2009) as well as a significant caseness for ASD among patients referring for depres- sion (Takara and Kondo, 2014b). Parallel, subjects with ASD have been https://doi.org/10.1016/j.psychres.2018.10.040 Received 2 May 2018; Received in revised form 25 September 2018; Accepted 15 October 2018 ⁎ Corresponding author. E-mail address: barbara.carpita1986@gmail.com (B. Carpita). Psychiatry Research xxx (xxxx) xxx–xxx 0165-1781/ © 2018 Elsevier B.V. All rights reserved. Please cite this article as: Dell'Osso, L., Psychiatry Research, https://doi.org/10.1016/j.psychres.2018.10.040