ADHD Incidence Trends Fluctuated from 2016 to 2023 in Adults, Adolescents

In recent years, the incidence of new ADHD diagnoses rose for adults and remained stable for adolescents. This data came from one of the largest retrospective cohort studies to investigate the incidence of new ADHD diagnoses among adolescents and adults before, during, and after the COVID-19 pandemic.

“These findings indicate that the incidence rate of ADHD diagnoses among adults and adolescents has fluctuated over the years, with distinct trends observed during different time periods,” wrote investigators, led by Margaret L. Paul, MS, from the department of psychology at Saint Louis University.

Investigators sought to examine the incidence and recent trends of a new ADHD diagnosis between 2016 and 2023. Participants (n = 144,103; mean age, 33.8 years) included adolescents (16.1%) and adults (84%) who used Sisters of Saint Mary healthcare services. The sample comprised mostly female (68.8%) and White (82.2%) participants.

The incidence of new ADHD diagnoses among adolescents and adults was 7.2%, and the annual incidence of ADHD in 2020 ranged from 0.67% to 1.15%. Adolescents aged 10 – 18 years had a yearly ADHD incidence rate that was more than double that of adults aged 19 – 50 years (1.36% - 2.89% vs 0.54 – 0.94%, respectively).

The study observed a significant downward trend (-10.6%; 95% confidence interval [CI], -25.0% to -2.8%) in ADHD incidence among adults from 2016 to 2020, followed by an upward trend from 2020 to 2023 (+15.2%; 95% CI, 2.0% to40.3%). Among adolescents, the analysis observed a significant downward trend in ADHD incidence from 2016 to 2018, dropping from 2.89% in 2016 to 1.53% in 2018 (−26.1%; 95% CI, −33.4% to −14.4%) and a stable trend from 2018 to 2023.

“Fluctuations in incidence rates are likely due to a complex interplay of various factors, such as increased knowledge and destigmatization of ADHD, changes in diagnostic practices, increased access to healthcare services and treatment-seeking patterns, and the impact of the COVID-19 pandemic on mental health,” investigators explained. “Increased awareness and destigmatization of ADHD can lead to more diagnoses being made, resulting in higher incidence rates.”

The team added how expanding the ADHD criteria in the DSM-5 could have contributed to the increase in diagnoses, although the variation of diagnostic practices and assessment methods across clinics and regions could impact incidence rates. Some clinics may be more stringent when following diagnostic criteria, using a full psychoeducational assessment, and some clinics may be more lenient and opt for brief screening measures.

The COVID-19 pandemic also contributed to the increase in mental health issues. The Mayo Clinic reported an increase in levels of stress, insomnia, anxiety, and depression during 2020 and 2021, which lowered by 2022, but the pandemic also affected levels of ADHD.2 During the pandemic, there were also reports of worsening ADHD symptoms and new onset diagnoses of ADHD, resulting in an increased ADHD incidence rate among adults.

Investigators wrote that the findings were limited by the lack of covariate adjustment in the joinpoint regression analysis, demographic variability with an overrepresentation of White individuals and females, and the use of data exclusively from the SSM healthcare system which includes participants from Illinois, Missouri, Oklahoma, and Wisconsin). Furthermore, the study did not explore the underlying factors contributing to ADHD incidence trends, leaving this an area for future research.

“In advancing our understanding of ADHD diagnostic trends in clinical practice, accurate diagnosis and management of ADHD can be promoted,” investigators wrote. “Findings from this study support future investigation in identifying potential modifiable risk factors, ensuring sufficient treatment resources, developing targeted interventions, and addressing diagnostic disparities.”

References

1. Paul, M, Sheth, P, David, R, et al. Incidence of Attention-Deficit/Hyperactivity Disorder Between 2016 and 2023: A Retrospective Cohort. Psychiatric Research and Clinical Practice. 2025. https://doi.org/10.1176/appi.prcp.20240121.
2. COVID-19 and Your Mental Health. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/coronavirus/in-depth/mental-health-covid-19/art-20482731. Accessed January 15, 2025.