Aging and Autism Spectrum Disorder: A Naturalistic, Longitudinal Study of the Comorbidities and Behavioral and Neuropsychiatric Symptoms in Adults with ASD.

Bao et al. (2017) tracked 74 adults with autism for about 25 years. They used medical charts and caregiver reports to see which problems got better, worse, or stayed the same.

The team counted 13 common issues like anxiety, mood swings, sleep trouble, and repetitive behaviors. They compared scores from early adulthood to scores in late adulthood.

Twelve of the 13 problems dropped significantly. Sleep issues, irritability, and anxiety faded the most. Core autism traits—social difficulty and restricted interests—hardly budged.

By their fifties, most adults still met autism criteria, but day-to-day life was calmer for them and their families.

Yarar et al. (2022) asked younger and older autistic adults to fill out surveys. They also saw that older groups felt less anxious and had better social quality of life, backing up the downward trend.

Parsons et al. (2019) looked at the same age band and found lots of medical issues—epilepsy, heart disease, stomach problems—yet those adults still reported fewer mood symptoms. The health load stays high even while behavior improves.

Leader et al. (2021) showed that sleep and stomach pain remain common in adults and drag down quality of life. A et al. agree these symptoms decline, but they rarely disappear, so screening is still needed.

You can reassure families that explosive behaviors often ease after forty, but you should not drop supports that target core social or adaptive skills. Keep anxiety and sleep screens on the care plan, and watch for hidden medical problems that pile up with age. Use the calmer baseline to teach new leisure or workplace skills while the client is less disrupted by irritability.