At the Autistic.co.il portal, we strive to bring up-to-date and relevant information to the adult autistic community in Israel. A new study published in Nord J Psychiatry, 2026 Jul, offers important insights into the link between Intellectual Developmental Disorder (IDD) and co-occurring mental health conditions, especially among individuals hospitalized due to severe self-harm.

Self-harm is a complex phenomenon that can be associated with a wide range of mental health conditions. In severe cases, requiring prolonged hospitalization, comorbidity-the co-occurrence of multiple mental disorders-is often present. This study focused on whether Intellectual Developmental Disorder might be an underlying factor in these cases, examining its link to a broader range of mental health conditions.

What Was Examined in the Study

The researchers included 42 adults hospitalized in psychiatric hospitals due to severe self-harm. Participants underwent comprehensive assessments including diagnostic interviews, a screening test for possible IDD (using a tool called HASI), and self-reported childhood trauma. The study's aim was to examine the link between possible IDD and various mental health conditions, and to test the effectiveness of a specific subscale within the HASI tool for initial identification of IDD.

Study Findings

  • The researchers report a significant link between the presence of possible IDD and a higher prevalence of co-occurring mental health conditions. This link remained even after statistical adjustment for conditions such as Borderline Personality Disorder (BPD), Substance Use Disorders (SUD), Autism, and childhood trauma.
  • Possible IDD and childhood trauma were found to be independently associated with the number of diagnosed mental health conditions.
  • The HASI tool's subscale used to assess background information showed good predictive ability in identifying possible IDD.

Significance of the Findings for Autistic Adults in Israel

These findings highlight the importance of proactive IDD assessment among individuals hospitalized due to severe self-harm, especially among those who also have Autism. An IDD diagnosis may open the door to a wider range of therapeutic accommodations, designed to specifically address the unique needs of individuals with complex developmental and psychological challenges.

Understanding the links between IDD, Autism, and other mental health conditions can help therapists build more personalized and comprehensive treatment plans, which will improve quality of life and reduce the risk of self-harm. It is important to remember that a correct diagnosis is the first step towards receiving appropriate support and treatment.

Limitations and Call for Further Research

It should be noted that the study included a relatively small sample of participants. Therefore, the findings should be considered preliminary and as such, intended to generate hypotheses for further research. Additional studies with larger samples are needed to confirm and expand these findings.