The Comorbidity between Autism Spectrum Disorder and Post-Traumatic Stress Disorder Is Mediated by Brooding Rumination

Student summary

Why This Research Matters

Autism spectrum disorder (ASD) frequently co-occurs with other mental health conditions such as ADHD, anxiety, and depression. Post-traumatic stress disorder (PTSD), however, has received far less research attention as a co-occurring condition in autistic adults, even though understanding shared mechanisms between ASD and other disorders can guide both diagnosis and treatment. This short report by Golan, Haruvi-Lamdan, Laor, and Horesh, published in the journal Autism in 2022, asked a focused question: does a thinking style called rumination help explain why autistic adults experience more post-traumatic stress symptoms?

Rumination is the tendency to repeatedly dwell on distressing thoughts or feelings. Researchers distinguish two types: brooding, a passive, self-critical, and unproductive style of dwelling on problems, and reflection, a more thoughtful, problem-solving style of processing emotions. The study team recruited 34 adults with ASD who had no intellectual impairment and 66 typically developing (TD) adults, matched for age and gender, so that any differences found could be attributed more confidently to autism rather than to demographic factors. Participants completed two self-report questionnaires: the PTSD Checklist for DSM-5 (PCL-5), which measures the severity of post-traumatic stress symptoms, and the Ruminative Response Scale, which separately scores brooding and reflective rumination.

The results showed two clear group differences. First, autistic adults reported significantly more post-traumatic stress symptoms than the TD comparison group. Second, autistic adults also reported significantly higher levels of brooding rumination than TD adults. The key analytic step in the study was a mediation analysis, a statistical technique used to test whether one variable (here, rumination) helps explain the relationship between two other variables (ASD status and PTSD symptoms). The findings showed that brooding rumination, but not reflective rumination, statistically mediated the link between ASD and PTSD symptom severity. In plain terms, part of the reason autistic adults in this sample had more severe PTSD symptoms appears to be connected to their tendency toward brooding, rather than autism status alone driving the difference.

The authors interpret this in the context of known cognitive patterns in ASD, particularly cognitive inflexibility, which is the difficulty shifting attention away from a fixed thought or behavior pattern. They suggest that this inflexibility may make it harder for autistic individuals who have experienced trauma to disengage from distressing, repetitive thoughts, which in turn could intensify or prolong post-traumatic symptoms. Because the study is described as a short report, it presents a focused, preliminary finding rather than an exhaustive investigation, and the authors explicitly call for future research to examine other psychological mechanisms that might also connect ASD and PTSD.

For nursing students, this research is a useful example of why comorbidity is not always simple to explain. Two conditions can appear together not just because one directly causes the other, but because a third factor, in this case a thinking pattern, links them. This has practical relevance for nurses working with autistic clients who have experienced trauma: screening for PTSD symptoms alone may not capture the full clinical picture, and a brief inquiry into ruminative thinking patterns could add valuable assessment information. This fits the trauma-informed, person-centred orientation that Canadian nursing regulators and best-practice guidance expect entry-level nurses to bring to mental health assessment. The authors also propose that interventions specifically targeting brooding rumination and cognitive flexibility, rather than generic trauma-focused approaches, may help reduce post-traumatic symptoms in autistic adults.

Students should also note the limits of this evidence. The sample was small (100 participants total, with only 34 in the ASD group), the design was cross-sectional so cause-and-effect cannot be confirmed, and participants were autistic adults without intellectual impairment, meaning the findings may not extend to the broader autistic population. The metadata record used for this article did not provide a working DOI link or open full text, so this summary relies on the detailed abstract and cross-verified bibliographic details (published in Autism, 2022, Volume 26, Issue 2, pages 538 to 544). Students seeking the complete statistical tables and discussion should consult the full journal article through a library database.

Faculty notes

Educational Relevance

This short report by Golan, Haruvi-Lamdan, Laor, and Horesh (Autism, 2022, 26(2), 538-544; DOI 10.1177/13623613211035240) addresses an underexamined comorbidity: post-traumatic stress disorder (PTSD) among autistic adults. While ASD's co-occurrence with ADHD, anxiety, and depression is well documented, the authors note that PTSD has received comparatively little empirical attention, despite its clinical relevance to trauma-informed care planning. The study's contribution is testing a candidate psychological mechanism, rumination, as a mediator of this comorbidity, distinguishing between brooding (a passive, self-critical rumination style) and reflection (a more adaptive, problem-solving style) via the two established subscales of the Ruminative Responses Scale.

Methodologically, the design is a between-groups comparison: 34 adults with ASD and no intellectual impairment versus 66 typically developing adults, matched on age and gender. Participants completed the PCL-5 (a validated, DSM-5-aligned PTSD symptom measure) and the Ruminative Response Scale. The authors report that the ASD group scored significantly higher on both PTSD symptoms and brooding rumination relative to controls, and that a mediation analysis indicated brooding, but not reflective rumination, significantly mediated the ASD-PTSD symptom association. This is a theoretically coherent finding: cognitive inflexibility, a well-established feature of ASD, plausibly interacts with brooding's repetitive, non-resolving quality to prolong or amplify post-traumatic distress.

For classroom use, this is a strong teaching case for mediation analysis versus simple group comparison, and for distinguishing correlation, mediation, and causation in comorbidity research. Students can be prompted to articulate why a third-variable mediator (rumination) is a more clinically actionable target than the ASD diagnosis itself, since it points toward a modifiable intervention lever (e.g., rumination-focused or cognitive-flexibility-oriented adaptations of trauma therapy) rather than an unmodifiable trait.

Limitations worth foregrounding in discussion include: the modest and unequal group sizes (34 versus 66), which constrain power and effect-size precision; the cross-sectional design, which cannot establish temporal precedence among ASD traits, rumination, and PTSD symptoms; the exclusion of autistic adults with intellectual impairment, limiting generalizability to a subgroup of the autism spectrum; and reliance on self-report instruments, which may be affected by known differences in interoceptive awareness or alexithymia sometimes reported in autistic populations. As a short report, the paper is also necessarily brief, and the authors explicitly flag that other psychological mechanisms beyond rumination remain unexamined.

The metadata packet available for this entry lacked a resolvable DOI and open full text; bibliographic verification (journal, volume, pages, and DOI) was confirmed via the publisher's indexing record and institutional repository listing rather than the primary PDF. Faculty assigning this article for appraisal exercises should have students independently retrieve the full text through a library database to review the complete statistical output (e.g., mediation coefficients, confidence intervals) before drawing firm clinical conclusions. This piece pairs well with the authors' earlier 2020 Autism paper on ASD-PTSD co-occurrence for a two-part module on comorbidity mechanisms and trauma-informed autism care.