Autism: The Real Reason It’s Going Up

What It Covers

Autism diagnoses increased five-fold in 25 years, reaching one in 31 US children. Research reveals the rise stems primarily from expanded diagnostic criteria capturing milder cases, not environmental toxins or vaccines.

Key Questions Answered

• •Genetic contribution: Seventy to ninety percent of autism risk comes from inherited genes, with maternal age over 40 increasing odds from 3.2% to 5.6%, though older parents explain only a small portion of rising diagnoses overall.
• •Diagnostic evolution: Autism definitions expanded from requiring severe intellectual disability and nonverbal presentation in the 1960s to including high-functioning individuals with specific interests and subtle social differences, capturing previously missed cases across all demographics.
• •Case severity data: Analysis of eight-year-olds from 2000 to 2016 shows severe autism cases requiring daily living assistance declined slightly, while the largest increase occurred in children with no measurable functional limitations requiring extra support.
• •Misdiagnosis patterns: Girls and non-white children historically received incorrect diagnoses like bipolar disorder instead of autism, leading to inappropriate treatments. Current diagnostic practices now identify these previously overlooked populations, contributing significantly to apparent case increases.