Elevated Suicidal Thoughts and Behaviors and Nonsuicidal Self-Injury in Autistic Youth and Adults: A Multinational...

Autistic people are at significant risk for suicidal thoughts and behaviors (STBs) and nonsuicidal self-injury (NSSI). We examined STB and NSSI in different age-groups, considering sex- and age-based effects, in a pooled multinational sample of English-speaking autistic children and adults.

We administered the Columbia-Suicide Severity Rating Scale to 245 autistic people without intellectual disability (139 youth and 106 adults; 46.1% female sex; M _age = 24.8, SD _age = 16.3 years, range = 7-70) or their caregivers in Australia, Canada, and the United States. The study samples were enriched with autistic people experiencing depression and suicidality.

Most participants (87.8%) reported suicidal ideation and NSSI (56.3%). Nearly one-third of autistic people (31.0%) reported a lifetime suicide attempt (M = 2.9 attempts; range = 1-26); overdosing was the most common method of suicide attempt. Sex was not a significant risk factor for suicidal ideation, behavior, or NSSI. Increases in lifetime suicidal ideation were observed across older age-groups, with those aged over 18 years reporting more severe and longer-lasting ideation than in children or adolescents. The youngest age of suicide attempt was 7 years in this sample, and the average ages of first/initial, most lethal, and most recent suicide attempts in youth (n = 24) and adults (n = 42) were 16.6, 19.2, and 20.8 years old, respectively.

Regardless of age-group, autistic people across the lifespan constitute a high-priority group for suicide prevention strategies, development of appropriate assessments, and evaluation of system-level programs that effectively address the problem of preventable death by suicide.