Effect of Parental Severe Mental Disorders on the Timing of Autism Diagnosis: A Family Linkage Study

The mean diagnosis age of autism was about 5 years in Taiwan. Whether the delayed diagnosis of autism (≥ 6 years) was associated with parental severe mental disorders remained unknown. The parents of 22,859 autistic individuals and 228,590 age- and sex-matched nonautistic individuals were assessed for the presence of severe mental disorders (schizophrenia, bipolar disorder, major depressive disorder, alcohol use disorder, and substance use disorder). The timing of autism diagnosis was classified into three age categories: