Transdiagnostic Clinical Burden of Insecure Attachment, Emotion Regulation Difficulties, and Alexithymia in Suicidal Behavior and Substance Use Disorder Publisher



Heydari M ; Abdollahpour Ranjbar H ; Modjtahedi S H ; Hassanian Moghaddam H ; Habibi Asgarabad M
Source: International Journal of Mental Health and Addiction Published:2026

Abstract

Background: Insecure attachment, difficulties in emotion regulation, and alexithymia have been independently linked to both suicidal behavior and substance use disorders. However, their joint contribution as intersecting, transdiagnostic mechanisms in comorbid clinical presentations remains insufficiently explored. Objective: Current study examined the associations of attachment insecurity, emotion regulation problems, and alexithymia across individuals with suicidal behavior, substance use disorder, their comorbidities, and healthy controls. Method: A total of 425 participants were recruited from hospital-based suicide units, addiction treatment centers, and community settings. Participants were categorized into four groups: individuals with comorbid suicidal behavior and substance use disorder (n = 100), suicidal behavior (n = 123), substance use disorder (n = 97), and healthy controls (n = 105). Clinical diagnoses were confirmed using the Structured Clinical Interview for DSM-5 – Clinician Version (SCID-5-CV). Suicidal behavior was assessed using the Columbia-Suicide Severity Rating Scale (C-SSRS), and participants completed validated measures of attachment [Experiences in Close Relationships–Revised (ECR-R]], emotion regulation [Difficulties in Emotion Regulation Scale (DERS]], and alexithymia [The Toronto Alexithymia Scale (TAS-20)]. Multivariate analysis of covariance and hierarchical regression analyses were performed. Results: All clinical groups displayed higher attachment anxiety and avoidance, more severe emotion regulation difficulties, and elevated alexithymia compared with control. The comorbid group showed the greatest impairments across all psychological domains. Emotion regulation difficulties were strongly associated with both attachment insecurity and alexithymic traits, suggesting an interconnected vulnerability profile. Conclusions: Attachment disturbances, emotional dysregulation, and alexithymia appear to form a shared vulnerability network underlying suicidal behavior and substance use disorders, with the greatest impairment in comorbid cases. The findings highlight the importance of interventions that enhance emotional awareness and regulatory capacity as transdiagnostic targets for prevention and treatment. © The Author(s) 2026.