This article has been clinically reviewed on April 15, 2022. 

An early, accurate diagnosis is always important—but it’s especially crucial when comorbidities exist. Current research shows that when autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) co-occur, symptoms of both are likely to be more severe. The sooner targeted therapies begin, the better outcomes are likely to be for people with these conditions. 

Here’s what we know about the social, educational, and mental health impacts of a dual diagnosis of ASD + ADHD. 

The risk of comorbidity is high 

ADHD is among the most common comorbidities with an ASD diagnosis. As many as 30%-80% of those with an ASD diagnosis also have ADHD symptoms significant enough to meet the diagnostic criteria for that disorder. Among children with ADHD, 20%-50% also have autism (Kernbach et al., 2018).  

Careful diagnosis may identify other mental health conditions 

Roughly three-quarters of those with ASD + ADHD also have at least one other mental health condition. Some of the most common are: 

• Depression  
• Anxiety 
• Substance use disorder 
• Separation anxiety disorder 
• Behavior disorders (Pehlivanidis et al., 2020)
  

Families, clinicians, and educators who are aware of the mental health risks can keep an eye on changing symptoms. Family education, regular screenings, and open conversations about mental wellbeing can be part of the treatment plan right from the start.   

Diagnosis and treatment can address the “additive” effect 

With a dual diagnosis, the problem isn’t simply that symptoms of two different conditions are present. There’s evidence to suggest that when these conditions coincide, symptoms of each condition become more severe.  

For example, ASD and ADHD disrupt the process of paying attention in different ways. When the conditions coexist, there is an additive effect on both types of disruption (Canigueral et al., 2021). Studies show a similar increase in impulsivity with ASD + ADHD (McClain et al., 2019). 

Early treatment can help students in the classroom  

ADHD symptoms can make learning more difficult for students with a dual diagnosis. More severe ADHD symptoms generally mean greater cognitive and behavioral problems—both of which affect academic progress (Mansour et al., 2017). There’s also evidence that added anxiety interferes with learning (Jogia et al., 2022).  

Now for the good news. Strategies that focus on helping students with working memory, planning, initiative, and organization of materials can improve ADHD symptoms and boost students’ attitude toward learning (Rosello et al., 2018).  

More focused interventions may be needed for social skills for children with ASD and ADHD 

ASD + ADHD may have a greater impact on social functioning than either condition might have on its own. For example, researchers in one study said boys with a dual diagnosis showed fewer pro-social behaviors than those diagnosed with ASD alone (Yamawaki et al., 2020). Prosocial behaviors include cooperating, comforting, and helping others.  

Here’s the takeaway: Interventions aimed at improving social skills can still make a powerful difference. One Swedish study found that a 24-week social skills program called KONTACT significantly improved social communication skills among students with ASD. Among those in the KONTACT program, 70% had a diagnosis of ASD + ADHD (Jonsson et al., 2019).  

Once again, the key is early intervention. When social skills training takes places at a young age, results are better (Fuller & Kaiser, 2020).  

Dual diagnosis has implications for medication choices 

Medication is an important part of the treatment plan for people with ASD + ADHD. Finding the precise combination of treatments can be more challenging with a dual diagnosis, though. 

The National Institute for Health and Care Excellence (NICE) in the U.K. recommends that people with ASD + ADHD be offered the same medication options as those with ADHD alone. The NICE guidelines add that healthcare providers should titrate doses slowly and monitor patients closely for side effects. Early diagnosis gives healthcare providers time to find the combination of medications that’s most effective for each individual.  

Earlier intervention can lead to better overall outcomes for children with ASD and ADHD 

Early identification isn’t a magic wand. ASD and ADHD are lifelong conditions. The challenges they present don’t disappear when the conditions are accurately diagnosed. Yet research into both conditions shows that earlier interventions often lead to better long-term outcomes (Towle et al., 2020; Wigal et al., 2020).  

Diagnosis takes time, especially with neurodevelopmental comorbidities. But an early, accurate diagnosis buys time. Time for clinicians to create individualized treatment plans. For educators to adapt the learning environment. For caregivers to learn about complex conditions. Those supports are critical for people with ASD + ADHD. 

Research and Resources: 

Cañigueral, R., Palmer, J., Ashwood, K.L., Azadi, B., Asherson, P., Bolton, P.F., McLoughlin, G. and Tye, C. (2022). Alpha oscillatory activity during attentional control in children with autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and ASD+ADHD. Journal of Child Psychology and Psychiatry. https://doi.org/10.1111/jcpp.13514 

Fuller, E. A., & Kaiser, A. P. (2020). The effects of early intervention on social communication outcomes for children with autism spectrum disorder: A meta-analysis. Journal of Autism and Developmental Disorders, 50(5), 1683–1700. https://doi.org/10.1007/s10803-019-03927-z 

Johansson, V., Sandin, S., Chang, Z., Taylor, M. J., Lichtenstein, P., D'Onofrio, B. M., Larsson, H., Hellner, C., & Halldner, L. (2020). Medications for attention-deficit/hyperactivity disorder in individuals with or without coexisting autism spectrum disorder: Analysis of data from the Swedish prescribed drug register. Journal of Neurodevelopmental Disorders, 12(1), 44. https://doi.org/10.1186/s11689-020-09352-z 

Leader, G., Dooley, E., Whelan, S., Gilroy, S.P., Chen, J.L., Barton, A.F., Coyne, R., & Mannion, A. (2021). Attention-deficit/hyperactivity disorder symptoms, gastrointestinal symptoms, sleep problems, challenging behavior, adaptive behavior, and quality of life in children and adolescents with autism spectrum disorder. Developmental Neurorehabilitation. DOI: 10.1080/17518423.2021.1964005 

Jonsson, U., Olsson, N. C., Coco, C., Görling, A., Flygare, O., Råde, A., Chen, Q., Berggren, S., Tammimies, K., & Bölte, S. (2019). Long-term social skills group training for children and adolescents with autism spectrum disorder: A randomized controlled trial. European Child & Adolescent Psychiatry, 28(2), 189–201. https://doi.org/10.1007/s00787-018-1161-9 

Liu, Y., Wang, L., Xie, S., Pan, S., Zhao, J., Zou, M., & Sun, C. (2021). Attention deficit/hyperactivity disorder symptoms impair adaptive and social function in children with autism spectrum disorder, Frontiers in Psychiatry, 12, 654485. https://doi.org/10.3389/fpsyt.2021.654485 

Mansour, R., Dovi, A. T., Lane, D. M., Loveland, K. A., & Pearson, D. A. (2017). ADHD severity as it relates to comorbid psychiatric symptomatology in children with autism spectrum disorders (ASD). Research in Developmental Disabilities, 60, 52–64. https://doi.org/10.1016/j.ridd.2016.11.009 

Pehlivanidis, A., Papanikolaou, K., Mantas, V., Kalantzi, E., Korobili, K., Xenaki, L. A., Vassiliou, G., & Papageorgiou, C. (2020). Lifetime co-occurring psychiatric disorders in newly diagnosed adults with attention deficit hyperactivity disorder (ADHD) or/and autism spectrum disorder (ASD). BMC Psychiatry, 20(1), 423. https://doi.org/10.1186/s12888-020-02828-1 

Rosello, B., Berenguer, C., Baixauli, I., Colomer, C., & Miranda, A. (2018). ADHD symptoms and learning behaviors in children with ASD without intellectual disability. A mediation analysis of executive functions. PloS One, 13(11), e0207286. https://doi.org/10.1371/journal.pone.0207286 

Towle, P. O., Patrick, P. A., Ridgard, T., Pham, S., & Marrus, J. (2020). Is earlier better? The relationship between age when starting early intervention and outcomes for children with autism spectrum disorder: A selective review. Autism Research and Treatment. https://doi.org/10.1155/2020/7605876 

Wigal, S., Chappell, P., Palumbo, D., Lubaczewski, S., Ramaker, S., & Abbas, R. (2020). Diagnosis and treatment options for preschoolers with attention-deficit/hyperactivity disorder. Journal of Child and Adolescent Psychopharmacology. 30(2), 104–118. https://doi.org/10.1089/cap.2019.0116 

Yamawaki K, Ishitsuka K, Suyama S, Suzumura S, Yamashita H, Kanba S. (2020). Clinical characteristics of boys with comorbid autism spectrum disorder and attention deficit/hyperactivity disorder. Pediatrics International. 62(2),151-157. https://onlinelibrary.wiley.com/doi/10.1111/ped.14105