Study suggests profile of people diagnosed with ADHD and autism has changed over the past decade

A study conducted by the Barcelona Institute for Global Health and Aarhus University reveals that children and adolescents diagnosed with ADHD or autism in Denmark today resemble their general population peers more closely than those diagnosed a decade ago. The research, published in JAMA Psychiatry, suggests that the increase in diagnoses over the past decade may be due to changes in the characteristics of the people receiving these diagnoses, rather than a true rise in the prevalence of these conditions.

Researchers analyzed data from over 2.1 million Danish children and adolescents, comparing those diagnosed with ADHD or ASD between 2012 and 2022 with more than 713,000 peers without these diagnoses. While diagnosed individuals still exhibit risk factors such as low birth weight, preterm birth, and socioeconomic disadvantage, the differences between them and their non-diagnosed peers have narrowed significantly.

For instance, the likelihood of being born with low birth weight was 54% higher for those diagnosed with ADHD or ASD a decade ago, but this gap has reduced to 17%. The study's findings highlight the need to consider changes in the diagnosed population when interpreting trends in ADHD and ASD prevalence and when planning health care, educational, and social services.