Childhood illnesses linked to psych disorders in autistic adults

Aug 5, 2026, Medical Express: Childhood physical illnesses linked to increased risk of mental health disorders in autistic young adults

Mental health conditions are more common among autistic individuals than in the general population, but knowledge about how physical and mental health interact over time has been limited. In the new study, researchers analyzed data from nearly 2 million individuals born in Sweden between 1985 and 2004, including more than 58,000 people diagnosed with autism.

The researchers investigated whether physical illnesses before age 16 were associated with psychiatric diagnoses between ages 16 and 25. The results, published in The Lancet Child & Adolescent Health, show that autistic individuals who experienced physical illnesses during childhood were more likely to receive psychiatric diagnoses in young adulthood than autistic individuals without such illnesses.

"Autistic individuals often experience a range of health conditions across their lives, yet these are frequently studied in isolation. These findings reinforce the importance of understanding health as interconnected across different body systems and stages of life," said Miriam Martini, a researcher at the Institute of Environmental Medicine, Karolinska Institutet.

Chronic pain and migraine were particularly associated with an increased risk of several psychiatric conditions. The researchers also found that the associations between childhood physical illnesses and later mental health disorders were stronger among females than males.

At the same time, the study shows that physical illnesses are only part of the explanation. Even autistic individuals without childhood physical illnesses had a higher risk of psychiatric disorders than people without autism.

"Physical health in childhood is only one piece of the puzzle. To improve mental health outcomes for autistic individuals, we also need to understand how social and environmental factors shape health across the life course and how these contribute to differences we see between autistic females and males," Martini said.

According to the researchers, the findings highlight the importance of paying attention to both physical and mental health in autistic children and adolescents. Better coordination between somatic and psychiatric health care could help identify care needs earlier and improve support during the transition to adulthood.

The study is based on data from Swedish national registers and includes diagnoses from both somatic and psychiatric specialist care.