Decreased Sound Tolerance Disorders (Hyperacusis and Misophonia) in Cognitively Able Autistic Adults II: Demographic and Clinical Correlates

Background: Between 50–70% of autistic individuals report clinically significant decreased sound tolerance (DST; i.e., difficulty tolerating sound in one’s environment) at some point in their lives. DST in autism comprises multiple distinct disorders, including hyperacusis (the perception of moderate-intensity sounds as excessively loud or physically painful) and misophonia (a neuropsychiatric condition in which specific “trigger” sounds cause excessive emotional reactions such as anger, irritation, and disgust), although few studies to date have distinguished these conditions from one another or studied their correlates independently. Methods: A sample of 936 independent autistic adults was recruited from the Simons Foundation Powering Autism Research for Knowledge cohort. Hyperacusis and misophonia case status were operationalized using self-report survey items reflecting DST symptom endorsement and functional impairment. Univariate and multivariate Bayesian models were then used to examine the demographic and clinical correlates of each DST diagnosis (both alone and independently of the other condition) in the autistic adult population. Results: Hyperacusis and misophonia were strongly correlated. Accordingly, all significant correlates in univariate analyses were found to associate with both conditions. In multivariate analyses (including control for depression and generalized anxiety, which strongly related to DST symptoms), both disorders were independently associated with female sex; increased autistic traits, attention-deficit/hyperactivity disorder (ADHD) symptoms, and phonophobia symptoms; and increased likelihood of seeking medical care for DST. Most other significant correlates (primarily hearing-related or neurological symptoms/disorders) were found to be associated only with hyperacusis rather than misophonia, although misophonia was uniquely associated with anger symptoms and identification as a gender minority. Conclusion: Both hyperacusis and misophonia explain substantial variance in clinical outcomes of interest in the autistic population and demonstrate utility as additional diagnoses for autistic adults who experience debilitating DST symptoms within clinical practice.