June 5, 2025

Meta-analysis Finds Little Evidence of Efficacy for Animal-Assisted Interventions for Treating Childhood ADHD

Study Background:

Animal-assisted interventions (AAIs) involve structured interactions with animals, designed and carried out by mental health teams assisted by trained human–animal professionals, to achieve specific therapeutic or educational goals. While a wide variety of animals may be used, horses and dogs tend to predominate. These interventions often involve physical contact, imitation, and play aimed at reducing stress and generating affection. Previous research has suggested that AAI to those with a range of developmental and mental health conditions.

Just how effective are they for treating ADHD in children and adolescents? Recent years have seen an increase in studies into AAIs for children with ADHD, but previous systematic reviews have not included quantitative meta-analysis to evaluate efficacy.

The Study:

A Chinese study team based in Nanjing set out to remedy that with a systematic search of the peer-reviewed published medical literature aimed at performing meta-analyses of efficacy.

The team limited its search to randomized controlled trials (RCTs) and pre–post single-group studies involving children and adolescents diagnosed with ADHD.

Meta-analysis of five studies with a combined total of 95 participants reported no significant effect of AAIs on ADHD symptom severity. There was negligible variation (heterogeneity) in outcomes among the studies.

Similarly, meta-analysis of the six studies encompassing 323 individuals found no significant improvements in social behavior. There was no heterogeneity and no sign of publication bias. Breaking that down into subcategories of social interaction (4 studies, 190 persons), social skill (3 studies, 53 persons), and problem behavior (4 studies, 80 participants) made no difference.

Likewise, meta-analysis of the three studies encompassing 61 individuals found no significant improvements in emotional control. Again, there was no heterogeneity and no sign of publication bias.

Three studies combining 56 participants reported no significant reductions in anxiety and depression, again with no heterogeneity and no sign of publication bias.

However, meta-analyses of five studies encompassing 194 individuals found a medium effect size association between AAIs and declines in attention problems, and a medium-to-large effect size improvement in learning and cognition. Heterogeneity was negligible to low.

Finally, meta-analysis of three studies combining 95 participants reported a large effect size improvement in motor proficiency, with moderate heterogeneity.

The Conclusion:

The team concluded, “As an ADHD management strategy complementary to gold-standard approaches, such as medication or multimodal interventions, AAIs did not appear to be more effective in improving the majority of core ADHD outcomes in children. Future studies should incorporate rigorous study designs with large sample sizes and a standard protocol to achieve more valid and reliable conclusions.”

Shuxin Yu, Hui Xue, Yuqing Xie, Guanyue Shao, Yihui Hao, Lijun Fan, and Wei Du, “Review: Animal-assisted intervention for children with attention-deficit/hyperactivity disorder – a systematic review and meta-analysis,” Child and Adolescent Mental Health (2025), 30, No. 1, 34-52, https://doi.org/10.1111/camh.12744.

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Acupuncture for ADHD: A Promising Alternative or Placebo? A Look at Recent Research

Attention Deficit Hyperactivity Disorder (ADHD) is a common condition affecting children and adolescents worldwide, characterized by symptoms such as hyperactivity, impulsivity, and inattention. While traditional treatments like medication and behavioral therapy are often used, some individuals are turning to complementary and alternative therapies (CAM) for help. One such option gaining attention is acupuncture. But does it really work for ADHD?

A recent comprehensive study aimed to evaluate the effectiveness of acupuncture in treating ADHD symptoms. Here’s a breakdown of the findings, with a focus on the age groups included in the research and what these findings could mean for ADHD treatment options.

What the Study Explored

The study in question conducted a systematic review and meta-analysis (SR/MA) of acupuncture trials for ADHD, comparing its effects to traditional treatments such as pharmacotherapy and behavioral therapy. The researchers focused on acupuncture’s impact on core ADHD symptoms like hyperactivity, impulsivity, inattention, and conduct problems, while also exploring how acupuncture might help with other issues, such as learning difficulties and psychosomatic symptoms.

One key feature of this study was the inclusion of a broad age range of participants, specifically children and adolescents. These two groups are the most commonly diagnosed with ADHD, and their responses to treatments can vary significantly. Understanding how acupuncture works for these age groups is critical for evaluating its effectiveness as an ADHD treatment.

Here’s what the study found across the different age groups:

  • Children: Acupuncture appeared to be particularly effective in reducing hyperactivity and impulsivity in younger children with ADHD. These symptoms, often more prominent in younger populations, responded well to acupuncture when used alongside other treatments like medication.

  • Adolescents: For adolescents, acupuncture seemed to improve both hyperactivity and inattention, two symptoms that can often become more challenging as children grow older. This age group also benefited from acupuncture’s ability to reduce side effects from ADHD medications, such as irritability or sleep disturbances.

  • Combined Effects for Both Groups: When acupuncture was used in combination with pharmacotherapy, it also helped reduce side effects such as sleep problems and appetite loss in both children and adolescents. This could make it an attractive adjunctive treatment for those already on medication but experiencing undesirable effects.

  • Inattention and Conduct Problems: For both children and adolescents, acupuncture used in conjunction with either medication or behavioral therapy showed notable improvements in inattention and conduct problems—two of the most difficult symptoms of ADHD to manage.

  • Learning Difficulties and Psychosomatic Symptoms: Interestingly, the combination of acupuncture and medication provided significant improvements in learning difficulties, which are particularly relevant for children with ADHD. Meanwhile, acupuncture paired with behavioral therapy had a positive impact on psychosomatic symptoms, such as anxiety or stress, that often co-occur with ADHD.

Despite these promising results, the study also highlighted several limitations:

  • Study Quality Issues: The quality of the studies reviewed was often low, with many trials lacking the rigorous controls needed for high confidence in their results. For example, only a small number of trials used objective ADHD diagnostic tools, which could lead to biases in assessing acupuncture’s effectiveness.

  • Need for More Research: There is a lack of large-scale, high-quality randomized controlled trials (RCTs) comparing acupuncture with placebo treatments, which makes it hard to determine whether acupuncture’s effects are truly therapeutic or simply a placebo.

Conclusion: Is Acupuncture a Good Option for ADHD?

In short, and as is so often the way of evidence-based medicine, we still can’t say with absolute certainty one way or the other. These studies may show promise in improving hyperactivity, impulsivity, inattention, and conduct problems– in both children and adolescents. However, the evidence is not yet strong enough to recommend it as a primary treatment. While it may serve as a helpful complement to standard therapies, especially for those struggling with medication side effects or access to behavioral therapy, more research is needed to establish its effectiveness.

April 21, 2025

Are Shared Care Models Effective in Treating Childhood ADHD?

Are Shared Care Models Effective in Treating Childhood ADHD?

A systematic review found five studies that evaluated shared care models involving children and adolescents, in which primary care providers(PCPs) collaborated with mental health care providers in treating ADHD. The 655 participants ranged in age from 5 to 17. Two of the studies were randomized.

In one, the largest, with 321 participants, care managers acted as liaisons between PCPs and psychiatrists and provided psychoeducation and skills training for families. Effect sizes on the Vanderbilt ADHD Diagnostic Teacher Rating Scale were very small, ranging from a standardized mean difference (SMDs) of 0.07 to 0.12. Improvement on the Clinical Global Impression scale was also small (SMD = 0.3)and was not significant (p = 0.4).

In the other randomized study, with 63 participants, care managers also acted as liaisons between PCPs and a psychiatric decision support panel to provide Positive Parenting Training. The SNAP-IV hyperactivity/impulsivity score showed a medium effect size (SMD = 0.7), with a medium-to-large effect size (0.7) for improvement in social skills. The score difference for SNAP-IV inattention was not statistically significant. The other three studies followed groups of individuals over time.

In one cohort with 129 participants, PSPs consulted with psychiatrists by telephone; an evaluation, where necessary, was performed within 4 weeks. As assessed by the Clinical Global Impression-Severity scale, symptoms declined from moderately severe to mild or borderline. On the Children's Global Assessment Scale, there was an improvement from problems in more than one area of functioning to just one area.

In another cohort with 116 participants, care managers acted as liaisons between pediatricians and a psychiatrist and provided education to parents. Just over a quarter of participants showed improvement of greater than one standard deviation on the Vanderbilt ADHD Diagnostic Parent Rating Scale, and just under one in seven on the Vanderbilt ADHD Diagnostic Teacher Rating Scale.

The remaining cohort had only 26 participants. It offered PCPs access to outpatient psychiatric consultations within three weeks. PCPs reported a high level of satisfaction with their improved skills in mental health care. There was no evaluation of the effect on symptoms.

With varied study designs, methodologies, and outcomes, the authors of the review could only conclude "that PCP collaboration with psychiatrists may be associated with the increased comfort level. However, the association with symptom outcome and increased capacity was variable." Given that randomized studies report only small effects, these shared care models cannot be routinely recommended.

July 22, 2021

Meta-Analysis: Physical Activity for Children and Adolescents with ADHD

Attention Deficit Hyperactivity Disorder (ADHD) is a prevalent neurodevelopmental disorder that significantly impacts children’s academic performance, social interactions, and overall quality of life (QoL). While medication is the standard treatment, it often comes with side effects and may not always provide sufficient benefits. A new systematic review and meta-analysis aims to investigate whether physical activity can offer a viable and effective alternative or complement to medication.

About the Study
This protocol, developed in line with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA) guidelines, focuses on randomized clinical trials involving children and adolescents (ages 3–18) diagnosed with ADHD or hyperkinetic disorder. The study's goal is to evaluate the effects of physical activity on:

  • Quality of life (QoL)
  • Executive functions
  • ADHD symptoms
  • Functional impairments

Unlike earlier reviews, which often included non-randomized trials or imposed limits on activity types, this analysis takes a more robust and inclusive approach. It is the first of its kind to examine QoL as an outcome while also incorporating trial sequential analysis—a method to assess evidence strength over time.

Why Physical Activity?
Physical activity is believed to impact the same brain systems targeted by ADHD medications, particularly the catecholaminergic system. This overlap suggests that exercise could play a key role in managing symptoms, potentially reducing reliance on medication or enhancing its effects.

Methodology Highlights

  • The review will adhere to principles outlined in the Cochrane Handbook for Systematic Reviews of Interventions.
  • It incorporates the latest research and focuses on randomized trials to ensure high-quality evidence.
  • No restrictions are placed on the frequency or intensity of physical activity interventions, making the findings broadly applicable.

Significance and Dissemination
The results of this systematic review will provide critical insights into how physical activity could improve outcomes for children and adolescents with ADHD. It is also notable as the first review in this field to prioritize quality of life—a crucial, often-overlooked measure of treatment success.

The findings will be published in peer-reviewed journals and presented at relevant conferences to inform clinicians, educators, and families.

Conclusion
As concerns about the limitations of ADHD medication grow, exploring alternatives like physical activity becomes increasingly important. This systematic review has the potential to shape future treatment strategies, offering children with ADHD a chance for better symptom management and a higher quality of life.

January 21, 2025

Beyond Dopamine: How Serotonin Influences ADHD Symptoms

ADHD is usually framed as a dopamine-and-norepinephrine condition, but recent studies have revealed that serotonin may also play a significant role. To delve deeper into this, we conducted a systematic literature review of studies looking at serotonin, its receptors, and the serotonin transporter (SERT) in relation to ADHD. The result: serotonin appears to be an important piece of the puzzle, but the overall picture is quite complex.

An ADHD & Serotonin Literature Review:

The authors searched the literature without time limits and screened thousands of records to end up with 95 relevant publications. Those included animal/basic-science work, neuroimaging, pharmacodynamics, a couple of large genetic/transcriptomic studies (GWAS and a cortico-striatal TWAS), and a few clinical reports. Each paper was graded for quality: 17 high, 59 medium, and 19 low.

The Results:
  • Most studies support a serotonergic role. About 81% (77/95) of the papers reported altered serotonin production, binding, transport, or degradation linked to ADHD or ADHD-like behaviors.

  • Multiple lines of evidence: animal models frequently show that changing serotonin levels or receptor activity alters hyperactivity and impulsivity; human imaging and clinical studies provide supportive but smaller and sometimes mixed signals; genetic/transcriptomic work points to serotonin-related pathways among many implicated systems.

  • Receptors and SERT matter: Multiple serotonin receptor subtypes (5-HT1A, 1B, 2A, 2C, 7) and SERT show associations with impulsivity, hyperactivity, attention, or brain activity patterns in ADHD models and some human studies.

  • Mixed and conflicting data: Central measures (brain, CSF) more often show serotonin deficits, while peripheral measures (platelets, plasma) sometimes show higher serotonin — methodological differences likely explain some contradictions.

  • Drugs used for ADHD can affect serotonin: Stimulants and non-stimulant drugs approved by FDA for treating ADHD (e.g., methylphenidate, atomoxetine, extended release viloxazine) or under investigation (centafafadine) have direct or indirect effects on serotonin systems, supporting the idea that monoamines interact rather than acting separately.  Because drugs that mainly affect serotonin are not useful for ADHD it seems likely that a pathway forward for ADHD drug development would be drugs that target multiple neurotransmitter systems.  A complex treatment for an etiologically complex disorder.

The Role of Serotonin in ADHD: What's The Take-Away?

As the study points out, the idea that serotonin may play a role in the neurobiology of ADHD is not new, but this literature review “identified multiple individual strands of evidence gathered over several decades and brought them into a more coherent focus”. It concludes that serotonergic neurotransmission is implicated in ADHD.  This doesn’t mean variations in serotonin levels cause ADHD, but that serotonin may be a plausible target for future treatments and research.

ADHD is polygenic and multi-systemic. For now, clinicians and patients should view serotonin as part of a complex network that may contribute to ADHD symptoms.  More research is needed before making treatment decisions based on these findings. 

Registry-based Cohort Study Finds No Association Between Maternal Diabetes and Offspring ADHD

Background:

A previous meta-analysis found that children born to mothers with diabetes had a 34% higher risk of developing ADHD compared to those born to non-diabetic mothers.  

However, previous studies suffered methodological limitations, such as small sample sizes, case-control or cross-sectional designs, and insufficient adjustment for key confounders such as maternal socio-economic status, mental health conditions, obesity, and substance use disorders.  

Moreover, many studies relied on self-reported maternal diabetes, and on non-clinical ADHD assessments, such as parental reports or screening tools, which are prone to bias and inaccuracies.  

Furthermore, the role of maternal antidiabetic medication use in relation to ADHD risk has rarely been examined. Antidiabetic medications are effective in controlling high blood sugar during pregnancy, but many can cross the placenta and the blood-brain barrier, raising concerns about potential effects on fetal brain development.  

Study:

To address these gaps, an Australian study team used a large cohort of linked health administrative data from New South Wales to investigate both the association between maternal diabetes and the risk of ADHD and the independent effect of prenatal exposure to antidiabetic medications. 

The study encompassed all mother-child pairs born from 2003 through 2005, with follow-up conducted through 2018 to monitor hospital admissions related to ADHD. That yielded a final cohort of almost 230,000 mother-child pairs. 

The team adjusted for potential confounders including maternal age, socioeconomic status, previous children, pregnancy-related hypertension, caesarean delivery, birth order and plurality, maternal anxiety, depression, schizophrenia, bipolar disorder, substance use (alcohol, tobacco, stimulants, opioids, cannabis), and child factors such as Apgar score, sex, prematurity, and low birth weight. 

Results:

For maternal diabetes overall, there was no significant association with offspring ADHD. That was also true when broken down into pre-existing maternal diabetes and gestational (pregnancy-induced) diabetes.  

In a subset of 11,668 mother-child pairs, including 3,210 involving exposure to antidiabetic medications, there was likewise no significant association with offspring ADHD

Conclusion:

The team concluded, “Our findings did not support the hypothesis that maternal diabetes increases the risk of ADHD in children. Additionally, maternal use of antidiabetic medication was not associated with ADHD.” 

This study highlights the importance of high-quality research. A previous meta-analysis linking ADHD and maternal diabetes did not appropriately adjust for confounders and cited many small studies that may have included biased self-report scales. This large, registry-based cohort study of nearly 230,000 mother–child pairs found no evidence that maternal diabetes—whether pre-existing or gestational—or prenatal exposure to antidiabetic medications was associated with subsequent offspring ADHD as measured by hospital-recorded ADHD outcomes. The study’s strengths include its population scale, prolonged follow-up, and extensive adjustment for maternal and perinatal confounders (including maternal mental health and substance-use disorders), which address many limitations of earlier, smaller studies that reported elevated risks.  

September 8, 2025

Population Study Finds Association Between COVID-19 Infection and ADHD

Background: 

The COVID-19 pandemic brought environmental changes that may have influenced ADHD symptoms and contributed to higher diagnosis rates. School closures, the transition to remote learning, and restrictions on outdoor activities led to increased screen time and isolation, both of which can affect attention and behavioral regulation. Children and adolescents, who usually depend on social interactions and structured routines, experienced significant disruptions during this period.  

Method:

South Korea has a nationwide single-payer health insurance system that keeps detailed health records on virtually its entire population. To explore the impact of COVID-19 on ADHD, a Korean research team used a database established by the Korean government that tracked all patients with COVID-19 between 2020 and 2023, nationwide COVID vaccination records, and insurance claims. They included all participants aged 6 through 29 years old. 

The onset of ADHD was determined by diagnosis combined with the prescription of ADHD medication. 

Altogether, the study encompassed almost 1.2 million Koreans, including over 150,000 children (6-12), more than 220,000 adolescents (13-19), and almost 800,000 young adults (20-29). 

The team adjusted for age, sex, income, Charlson Comorbidity Index, and medical visits. The Charlson Comorbidity Index predicts the mortality for a patient who may have a range of 17 concurrent conditions, such as heart disease, AIDS, or cancer. 

Results:

With these adjustments, young adults known to be infected with COVID-19 were about 40% more likely to be subsequently diagnosed with ADHD than their counterparts with no record of such infection

Adolescents known to be infected with COVID-19 were about twice as likely to be subsequently diagnosed with ADHD than their counterparts with no record of such infection. 

Children known to be infected with COVID-19 were 2.4 times as likely to be subsequently diagnosed with ADHD than their counterparts with no record of such infection

All these results were highly significant, and point to much greater impact on the youngest persons infected. 

Interpretation: 

The team concluded, “our nationwide study revealed that the COVID-19 pandemic significantly influenced ADHD incidence (raising incidence between 2020 and 2023), with SARS-CoV-2 infection identified as a critical risk factor,” and “In particular, early intervention and neurological evaluations are needed for children, adolescents, and young adults with a history of SARS-CoV-2 infection.”