Study Shows 450 Percent Jump in Adult Autism Diagnoses, Suggesting a Trend in Late Diagnosis

Women and racial minorities have also seen a significant increase in diagnosis rates.

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The number of Americans diagnosed with autism spectrum disorder (ASD) has nearly tripled over the past decade, with young adults aged 26 to 34 showing the most dramatic surge—a 450 percent increase, according to a new cross-sectional study published in JAMA Psychiatry on Wednesday.

From 2011 to 2022, overall autism diagnosis rates increased by 175 percent, the authors found.