The DSM-5 recognized that the separation anxiety disorder (SEPAD) may span the entire life course or have an adult-onset. Epidemiological data indicated a 23%–69% prevalence of SEPAD in clinical settings and a high comorbidity with both prolonged grief disorder (PGD) and post-traumatic stress disorder (PTSD). Some authors hypothesize that while life threat represents the key trigger of PTSD, disruptions or threats to interpersonal bonds lead to PGD and SEPAD. This study aims to test the hypothesis that adult-onset SEPAD might be a trauma-related disorder, triggered by events threatening to interpersonal bonds.

The sample included 106 consecutive adult outpatients with anxiety and/or mood disorders. SEPAD was diagnosed according to DSM-5 criteria by means of the Structured Clinical Interview for Separation Anxiety Symptoms (SCI-SAS). The Adult Separation Anxiety Checklist (ASA-27) was used to assess symptoms severity. To assess exposure to trauma, the SCID-5 criterion A form for PTSD was administered. Traumatic events were coded as directly experienced (self) or involving close ones (others). Lifetime exposure to separation events was also assessed.

60.4% of participants were categorized as not having SEPAD in adulthood or in childhood (NO-SEPAD), 18.9% as childhood-onset SEPAD, and 20.8% as adult-onset SEPAD. Controlling for comorbid disorders, lifetime traumatic events involving self and separation events, traumatic events involving others significantly predicted adult-onset SEPAD. A significant correlation between the age at trauma exposure and the age of SEPAD onset was found.

Our results are consistent with the hypothesis that adult-onset SEPAD may represent an event-related disorder.