April 1, 2021

Smart People Can Have ADHD Too

We know from many studies that ADHD is associated with a slightly lower intelligence quotient (IQ) and with problems in thinking known as executive function deficits. If that's the case, you might think that people with a high IQ cannot have ADHD.  You would be wrong. Data on groups sometimes mislead us about individuals. Although on average, ADHD people have IQ scores that are about 9 points lower than others, there is a wide spread of IQs in both ADHD and non-ADHD people. So many people with ADHD have higher IQs than those without ADHD and vice-versa. Moreover, studies of people with high IQs support the idea that ADHD can be validly diagnosed among very intelligent individuals.

A series of studies using Antshel and colleagues showed that the clinical profile of high IQ ADHD was very similar to what has been observed for ADHD in general. For example, like their less intelligent counterparts, high IQ ADHD children have an increased risk for mood, anxiety, and disruptive behavior disorders. Children with a high IQ and ADHD showed a pattern of familial transmission as well as cognitive, psychiatric, and behavioral impairments consistent with the diagnosis of ADHD. The degree to which ADHD persisted into adulthood was also similar between the two groups.

In studies of adults with ADHD, the same group concluded that "adults with ADHD and a high IQ display patterns of functional impairments, familiarity and psychiatric co-morbidities that parallel those found in the average-IQ adult ADHD population." Of particular interest, despite their high intelligence, High-IQ adults with ADHD show impaired executive functioning, and their performance on tests of executive functioning predicted life impairments.

Why are these data important? 
Milioni and colleagues argue that among higher IQ adults with ADHD, a higher degree of intellectual efficiency may compensate for deficits in executive functions. This ability to compensate allows them to succeed in many tasks, which otherwise might have been impaired by their ADHD symptoms. But, in many cases, such compensation is not sufficient or is too burdensome. When compensation fails, ADHD symptoms and other impairments emerge. When this occurs later in life, some clinicians are reluctant to diagnose ADHD. Caution is warranted, but clinicians need to know that the diagnosis of ADHD among high IQ is valid.

Antshel, K. M., S. V. Faraone, et al. (2008). "Temporal stability of ADHD in the high-IQ population: results from the MGH Longitudinal Family Studies of ADHD." J Am Acad Child Adolesc Psychiatry47(7): 817-825.
Antshel, K. M., S. V. Faraone, et al. (2009). "Is adult attention deficit hyperactivity disorder a valid diagnosis in the presence of high IQ?" Psychol Med39(8):1325-1335.
Antshel, K. M., S. V. Faraone, et al. (2010)."Executive functioning in high-IQ adults with ADHD."Psychol Med40(11): 1909-1918.
Antshel, K. M., S. V. Faraone, et al. (2007). "Inattention deficit hyperactivity disorder a valid diagnosis in the presence of high IQ? Results from the MGH Longitudinal Family Studies of ADHD."child Psychol Psychiatry48(7): 687-694.
Katusic, M. Z., R. G. Voigt, et al. (2011)."Attention-deficit hyperactivity disorder in children with high intelligence quotient: results from a population-based study." JDevBehavPediatr32(2): 103-109.

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Evidence-Based Interventions for ADHD

EBI-ADHD: 

If you live with ADHD, treat ADHD, or write about ADHD, you’ve probably run into the same problem: there’s a ton of research on treatments, but it’s scattered across hundreds of papers that don’t talk to each other.  The EBI-ADHD website fixes that. 

EBI-ADHD (Evidence-Based Interventions for ADHD) is a free, interactive platform that pulls together the best available research on how ADHD treatments work and how safe they are. It’s built for clinicians, people with ADHD and their families, and guideline developers who need clear, comparable information rather than a pile of PDFs. EBI-ADHD Database  The site is powered by 200+ meta-analyses covering 50,000+ participants and more than 30 different interventions.  These include medications, psychological therapies, brain-stimulation approaches, and lifestyle or “complementary” options. 

The heart of the site is an interactive dashboard.  You can: 

  1. Choose an age group: children (6–17), adolescents (13–17), or adults (18+). 
  1. Choose a time frame: results at 12, 26, or 52 weeks. 
  1. Choose whether to explore by intervention (e.g., methylphenidate, CBT, mindfulness, diet, neurofeedback) or by outcome (e.g., ADHD symptoms, functioning, adverse events), depending on what’s available. EBI-ADHD Database 

The dashboard then shows an evidence matrix: a table where each cell is a specific treatment–outcome–time-point combination. Each cell tells you two things at a glance: 

  1. How big the effect is, compared to placebo or another control (large benefit, small benefit, no effect, small negative impact, large negative impact). 
  1. How confident we can be in that result (high, moderate, low, or very low certainty).  

Clicking a cell opens more detail: effect sizes, the underlying meta-analysis, and how the certainty rating was decided. 

EBI-ADHD is not just a curated list of papers. It’s built on a formal umbrella review of ADHD interventions, published in The BMJ in 2025. That review re-analyzed 221 meta-analyses using a standardized statistical pipeline and rating system. 

The platform was co-created with 100+ clinicians and 100+ people with lived ADHD experience from around 30 countries and follows the broader U-REACH framework for turning complex evidence into accessible digital tools.  

Why it Matters 

ADHD is one of the most studied conditions in mental health, yet decisions in everyday practice are still often driven by habit, marketing, or selective reading of the literature. EBI-ADHD offers something different: a transparent, continuously updated map of what we actually know about ADHD treatments and how sure we are about it. 

In short, it’s a tool to move conversations about ADHD care from “I heard this works” to “Here’s what the best current evidence shows, and let’s decide together what matters most for you.” 

Meta-analysis Finds Tenuous Links Between ADHD and Thyroid Hormone Dysregulation

The Background:

Meta-analyses have previously suggested a link between maternal thyroid dysfunction and neurodevelopmental disorders (NDDs) in children, though some studies report no significant difference. Overweight and obesity are more common in children and adolescents with NDDs. Hypothyroidism is often associated with obesity, which may result from reduced energy expenditure or disrupted hormone signaling affecting growth and appetite. These hormone-related parameters could potentially serve as biomarkers for NDDs; however, research findings on these indicators vary. 

The Study:

A Chinese research group recently released a meta-analysis examining the relationship between neurodevelopmental disorders (NDDs) and hormone levels – including thyroid, growth, and appetite hormones – in children and adolescents.  

The analysis included peer-reviewed studies that compared hormone levels – such as thyroid hormones (FT3, FT4, TT3, TT4, TSH, TPO-Ab, or TG-Ab), growth hormones (IGF-1 or IGFBP-3), and appetite-related hormones (leptin, ghrelin, or adiponectin) – in children and adolescents with NDDs like ADHD, against matched healthy controls. To be included, NDD cases had to be first-diagnosis and medication-free, or have stopped medication before testing. Hormone measurements needed to come from blood, urine, or cerebrospinal fluid samples, and all studies were required to provide both means and standard deviations for these measurements. 

Meta-analysis of nine studies encompassing over 5,700 participants reported a medium effect size increase in free triiodothyronine (FT3) in children and adolescents with ADHD relative to healthy controls. There was no indication of publication bias, but variation between individual study outcomes (heterogeneity) was very high. Further analysis showed FT3 was only significantly elevated in the predominantly inattentive form of ADHD (three studies), again with medium effect size, but not in the hyperactive/impulsive and combined forms

Meta-analysis of two studies combining more than 4,800 participants found a small effect size increase in thyroid peroxidase antibody (TPO-Ab) in children and adolescents with ADHD relative to healthy controls. In this case, the two studies had consistent results. Because only two studies were involved, there was no way to evaluate publication bias. 

The remaining thyroid hormone meta-analyses, involving 6 to 18 studies and over 5,000 participants in each instance, found no significant differences in levels between children and adolescents with ADHD and healthy controls

Meta-analyses of six studies with 317 participants and two studies with 192 participants found no significant differences in growth hormone levels between children and adolescents with ADHD and healthy controls. 

Finally, meta-analyses of nine studies with 333 participants, five studies with 311 participants, and three studies with 143 participants found no significant differences in appetite-related hormone levels between children and adolescents with ADHD and healthy controls. 

The Conclusion:

The team concluded that FT3 and TPO-Ab might be useful biomarkers for predicting ADHD in youth. However, since FT3 was only linked to inattentive ADHD, and TPO-Ab’s evidence came from just two studies with small effects, this conclusion may overstate the meta-analysis results. 

Our Take-Away:

Overall, this meta-analysis found only limited evidence that hormone differences are linked to ADHD. One thyroid hormone (FT3) was higher in children with ADHD—mainly in the inattentive presentation—but the findings varied widely across studies. Another marker, TPO-Ab, showed a small increase, but this came from only two studies, making the result less certain. For all other thyroid, growth, and appetite-related hormones, the researchers found no meaningful differences between children with ADHD and those without. While FT3 and TPO-Ab may be worth exploring in future research, the current evidence is not strong enough to consider them reliable biomarkers.

 

December 15, 2025

Meta-analysis Finds Assisted Reproductive Techniques Associated with Offspring ADHD

Meta-analysis Finds Assisted Reproductive Techniques Associated with Offspring ADHD 

Background:

Recent progress in reproductive medicine has increased the number of children conceived via assisted reproductive techniques (ART). These include: 

  • In vitro fertilization (IVF), in which eggs are retrieved from the ovaries and fertilized with sperm in a laboratory; embryos are then transferred into the uterus.  
  • Intracytoplasmic sperm injection (ICSI), where a single sperm is injected directly into an egg. 
  • Intrauterine insemination (IUI), in which sperm is placed directly into the uterus around the time of ovulation. This is often combined with ovulation-inducing (OI) medications. 

Although ART helps with infertility, there are concerns about its long-term effects on offspring, especially regarding neurodevelopment. Factors such as hormonal treatments, gamete manipulation, altered embryonic environments, as well as parental age and infertility, may influence brain development and raise the risk of neurodevelopmental and mental health disorders. 

With previous studies finding conflicting results on a possible association between ART and increased risk of mental health disorders, an Indian research team has just published a new meta-analysis exploring this topic. 

The Study:

Studies were eligible if they were observational (cohort, case-control, or cross-sectional), reported confounder-adjusted effect sizes for ADHD, and were published in English in peer-reviewed journals. 

A meta-analysis of eight studies encompassing nearly twelve million individuals indicated a 7% higher prevalence of ADHD in offspring conceived via IVF/ICSI compared to those conceived naturally. The heterogeneity among studies was minimal, and no evidence of publication bias was observed. 

The study’s 95% confidence interval ranged from 4% to 10%. Further analysis of five studies comprising almost nine million participants that distinguished outcomes by sex revealed that the increase in ADHD risk among female offspring was not statistically significant. In contrast, the elevated risk in male offspring persisted, though it was marginally significant, with the lower bound of the confidence limit at only 1%. 

Results:

A meta-analysis of three studies (1.4 million participants) found a 13% higher rate of ADHD in children conceived via ovulation induction/intrauterine insemination (OI/IUI) compared to natural conception. The effect size, though doubled, remains small. Minimal heterogeneity and no publication bias were observed. 

The team concluded, “The review found a small but statistically significant moderate certainty evidence of an increased risk of ADHD in those conceived through ART, compared to spontaneous conception. The magnitude of observed risk is small and is reassuring for parents and clinicians.” 

Our Take-Away:

Overall, the meta-analysis points to a small, but measurable increase in ADHD diagnoses among children conceived through ART, but the effect sizes are modest and supported by moderate-certainty evidence. And we must always keep in mind that the researchers who wrote the original articles could not correct for all possible confounds.  These findings suggest that while reproductive technologies may introduce slight variation in neurodevelopmental outcomes, the effects are small and uncertain. For families and clinicians, the results are generally reassuring: ART remains a safe and effective avenue to parenthood, and the results of this study should not be viewed as a prohibitive concern. Thoughtful developmental monitoring and open, evidence-based counseling can help ensure that ART-conceived children receive support that caters to their individual needs.

 

December 12, 2025