Did you know, research has suggested that “Attention-Deficit-Hyperactivity-Disorder” (ADHD) has a prevalence of approximately 5% (Polanczyk et al., 2007). That means that about 1-2 children in every class in the country will experience clinically significant difficulties with inattention, hyperactivity, and/or impulsivity. I don’t know about you, but that sounds incredibly high to me!
To receive a diagnosis of ADHD, an individual must experience some of these difficulties to a greater extent than is developmentally expected. Difficulties must also cause a significant level of impairment in at least two major domains of psychosocial functioning (i.e., education, social relationships, self-esteem, etc.) (APA, 2013).
Aside from obvious difficulties, there are a cluster of secondary difficulties that may manifest from this neurodevelopmental condition. Some examples include motor (Kaiser et al., 2015), social (Sibley et al., 2010), and mental health (Langley et al., 2017) related difficulties. Moreover, ADHD has been linked to a vast array of co-morbid mental health conditions, learning disorders, and neurodevelopmental disorders (French et al., 2024). The list of risks and outcomes associated with ADHD unfortunately goes on.
As you can imagine, there is a significant breadth of research in this field. Due to this, many existing reviews have imposed strict guidelines on their search criteria. Could this have led to gaps in the existing literature?
I present to you a paper targeting this: French et al. (2024). Their aim:
To synthesise the adverse impacts that ADHD has on children and adults, with regards to physical and mental health, and social and lifestyle functioning.
This umbrella review aimed to explore the adverse impacts that ADHD has on children and adults in relation to physical health, mental health, social functioning and lifestyle risks.
Methods
This study proposed an interesting approach. A review of existing reviews that have reviewed the outcomes (i.e., impacts, long-term outcomes, and risks) associated with ADHD. What a mouth full! In simple terms, the researchers carried out an ‘umbrella review’.
Reviews published before July 2023 were considered for eligibility (including international reviews). While any methodological design was considered, eligible research had to have been peer-reviewed. Reviews including participants who met diagnostic criteria or were formerly diagnosed with ADHD were considered eligible.
The authors searched five research databases. From the research that was included, reference lists were searched for further eligible reviews. Titles and reviews were screened independently by two separate reviewers. Two reviewers then completed full-text assessments of the remaining reviews. Study quality was analysed using the SANTRA scale and Kmet, Lee and Cook (2004) guidelines.
Finally, a narrative synthesis was completed after findings from the qualitative and quantitative components of these reviews were aggregated.
Results
125 reviews were included in the analysis. The publication dates of these reviewes ranged from 1991 to 2023. They originated from a number of different countries and utilised a large amount of different review methodologies (including meta-analyses).
The researchers reported that under half (42%) of the included reviews were identified to be “good” in quality, according to the SANTRA scale and Kmet, Lee and Cook (2004) guidelines. However, it must also be acknowledged that only 10% of the included reviews were identified to be “poor” in quality.
The researcher’s narrative synthesis identified 3 clusters of risks related to ADHD.
Mental health risks (42 reviews), including:
- Addiction (16 reviews). ADHD was found to be associated with an increased risk of nicotine, alcohol and substance misuse, internet, sex and gaming addictions and problem gambling.
- Suicide and self-harm (8 reviews). ADHD was found to be associated with self-harming behaviours and suicide (i.e., suicidal behaviours, attempts, ideations, and completed suicides) in all 8 papers though, it is unclear whether this is mediated by other comorbidities such as delinquency and substance misuse.
- Mental disorders and self-esteem (16 reviews). ADHD was found to be associated with a risk of bipolar disorder, depression, borderline personality disorder and schizophrenia in adults. Further, it was associated with an increased risk of OCD and eating disorders in children and young people. ADHD was also associated with low self-esteem in adulthood.
Physical health risks (51 reviews). including:
- Sleep (13 reviews). ADHD was found to be associated with childhood and adulthood-related difficulties in a range of sleep issues and was more prevalent in those who experience narcolepsy and obstructive sleep apnoea.
- Oral health (6 reviews). ADHD was found to be associated with tooth grinding, clenching and dental trauma in children and adolescents.
- Weight (9 reviews). Those with ADHD were found to have a higher weight and BMI as well as a larger risk of obesity; there was a 70% increase in adults and a 40% increase in children with ADHD.
- Accidents and injuries (8 reviews). ADHD was found to be associated with higher rates of poisonings, unintentional injuries and death due to unnatural causes. Further, there was a small amount of evidence linking ADHD to brain injuries, though the direction of this relationship remained unclear.
- Diseases and impairments (15 reviews). ADHD was found to be associated with higher risk of asthma, chronic pain, celiac disease, vision related impairments, type 2 diabetes, neurodegenerative diseases in aging populations and cardiovascular disease. Conversely, ADHD was associated with lower urinary tract symptoms.
Social and lifestyle risks (32 reviews), including:
- Offending, criminality, and violence (9 reviews). ADHD was found to be associated with offending behaviours, increased risk of re-offending and an increased risk of victimisation. ADHD had a high prevalence amongst forensic populations regardless of age and gender.
- Employment and education (5 reviews). ADHD was found to be associated with a need for additional support in schools, early exit from education, poorer educational outcomes, employment performance and employment maintenance.
- Quality of life (5 reviews). Increasing ADHD symptom severity predicted poorer outcomes on quality-of-life measures in adults and children. However these negative effects were less robust when children rated their own quality-of-life, as opposed to their parents.
- Relationships and social interactions (5 reviews). ADHD was found to impact childhood peer functioning, social skills and the relationships formed with teachers. It was also associated with impacts to adult intimate relationships, intimate partner violence and parenting difficulties in adulthood.
- Risk taking (5 reviews). ADHD was found to be associated with an increased risk of driving accidents and teenage pregnancy.
ADHD has been associated with more than just inattention and high energy levels. Even oral health is impacted by ADHD!
Conclusions
Establishing the relationship between ADHD and different adverse outcomes was the aim of this study. As can be seen above, there are a wide range of mental health, physical health, and social and lifestyle functioning risks that are associated with ADHD.
The mapping of ADHD related difficulties appears more difficult than one would typically expect.
Strengths and limitations
Strengths:
- The researchers adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) (Page et al., 2021) guidelines. They therefore demonstrated their commitment to reliability and high-quality research.
- The researchers included any research that was published before July 2023. As a result, this research included reviews that dated as far back as 1991. This gave the researcher the opportunity to identify any issues in the temporal validity of their findings.
Limitations:
- The researchers reported that 9 reviews were excluded as they were not published in English. In addition to the unique perspectives that these excluded reviews may have offered, the exclusion of these reviews calls into question whether this research truly offers an international perspective.
- The researchers reported that a diagnosis of ADHD was based on a variety of methods. Some of these methods include “achieving a specified cut-off on a validated measure”. However, the identity of these measures was not provided. This does not allow the reader to critique the quality of these measures for themselves.
- Under half (42%) of the included reviews were identified to be “good” in quality. Could some form of bias have been implicated within the remaining reviews findings?
- What about the studies that haven’t yet been included within a review? Could these studies have identified lesser-known risks?
The researchers were transparent about their research protocol and search strategies. This leaves room for other researchers to pick up where French et al. (2024) left off.
Implications for practice
This review has implications for services and may be used to explore future policy development and care pathways. For example, these findings advocate for the development of ADHD-specific interventions (i.e., tailored exercise programmes, diet management programmes, and psychoeducational packages) that are targeted at improving outcomes for those diagnosed with ADHD. The hope is that these interventions would provide client-centred care that considers and mitigates existing difficulties with core ADHD symptomology. Furthermore, there are hopes that this review will provide future researchers with the opportunity to compare their findings with previous research. Hopefully this will allow for further advancements in this important field.
This research paper is a useful document for a wide target audience, including those diagnosed with ADHD and clinicians, services, and future researchers. Future research should also explore under-represented areas of research. These include the areas of gender dysphoria and self-esteem.
Having worked as a supporting clinician responsible for carrying out ADHD assessments, I am excited to see that further research is being conducted to benefit those diagnosed with ADHD. While a diagnosis of ADHD can be a positive and validating experience, there is a need for post-diagnostic support. The development of patient-centred interventions will only improve wider outcomes for those who need it most.
While a diagnosis of ADHD can be a positive and validating experience, clearly there is a need for post-diagnostic support in a wide range of areas.
Statement of interests
No formal conflicts of interest.
Links
Primary paper
French, B., Nalbant, G., Wright, H., Sayal, K., Daley, D., Groom, M. J., … & Hall, C. L. (2024). The impacts associated with having ADHD: an umbrella review. Frontiers in psychiatry, 15, 1343314.
Other references
APA. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC: APA.
Kaiser, M. L., Schoemaker, M. M., Albaret, J. M., & Geuze, R. H. (2015). What is the evidence of impaired motor skills and motor control among children with attention deficit hyperactivity disorder (ADHD)? Systematic review of the literature. Research in developmental disabilities, 36, 338-357.
Kmet, L. M., Lee, R. C., & Cook, L. S. (2004). Alberta Heritage Foundation for Medical Research. Standard quality assessment criteria for evaluating primary research papers from a variety of fields.
Langley, K., Pozo-Banos, M. D., Daalsgard, S., Paranjothy, S., Riglin, L., John, A., & Thapar, A. (2023). ADHD and Autism Spectrum Disorder (ASD) in Childhood: establishing the feasibility and validity of a nation-wide e-cohort. medRxiv, 2023-01.
Polanczyk, G., De Lima, M. S., Horta, B. L., Biederman, J., & Rohde, L. A. (2007). The worldwide prevalence of ADHD: a systematic review and metaregression analysis. American journal of psychiatry, 164(6), 942-948.
Sibley, M. H., Evans, S. W., & Serpell, Z. N. (2010). Social cognition and interpersonal impairment in young adolescents with ADHD. Journal of Psychopathology and Behavioral Assessment, 32, 193-202.
