Previous studies reported a high prevalence of depression among patients with autism spectrum disorder (ASD) and suggested a relationship between ASD and suicidality. However, whether ASD independently increases the risk of attempted suicide regardless of depression has not been determined.
Using the Taiwan National Health Insurance Research Database, 5,618 adolescents aged 12-17 years and young adults aged 18-29 years with ASD (ICD-9-CM code: 299) and 22,472 age- and sex-matched controls were enrolled between 2001 and 2009 and followed to the end of 2011. Any suicide attempt was identified during the follow-up period.
Patients with ASD had a higher incidence of suicide attempts (3.9% vs 0.7%, P < .001) than did those without ASD. Both adolescents (HR = 5.79; 95% CI, 3.98-8.41) and young adults (HR = 5.38; 95% CI, 3.58-8.06) with ASD were more likely to attempt suicide in later life after adjusting for demographic data and psychiatric comorbidities. Sensitivity analyses after excluding the first year (HR = 4.52; 95% CI, 3.39-6.03) or first 3 years (HR = 3.36; 95% CI, 2.40-4.70) of observation showed consistent findings.
Patients with ASD had an increased risk of suicide attempts compared with those without ASD. ASD was an independent risk factor of attempted suicide. Further studies are needed to clarify the underlying pathophysiology between ASD and suicidality and to elucidate whether prompt intervention for ASD may reduce this risk.