Meta-Analysis: Maternal Folic Acid Supplementation Reduces Risk of ADHD in Offspring

Recent research from the Centers for Disease Control and Prevention (CDC) highlights distinct health and social-emotional challenges faced by teens diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD). This study, published in the Journal of Developmental and Behavioral Pediatrics, offers critical insights directly from the teens themselves, providing a unique view often missed when relying solely on parent or clinical reports. 

Researchers analyzed nationally representative data from July 2021 through December 2022, comparing self-reported experiences of teens aged 12 to 17 with and without ADHD. Approximately 10% of teenagers had an ADHD diagnosis, and the findings reveal specific areas where teens with ADHD face notable difficulties. 

Teenagers with ADHD reported significantly higher rates of bullying victimization and struggles in making friends compared to their peers. Surprisingly, they were less likely to report a lack of peer support, suggesting complexities in how they perceive friendships and social networks. The study underscores the importance of directly engaging teens in assessing their social relationships, rather than solely relying on parental perspectives. 

Sleep difficulties emerged as another critical issue for teens with ADHD. About 80% reported problems like difficulty waking up and irregular wake times, markedly higher than their non-ADHD counterparts. Such disruptions can exacerbate attention difficulties and emotional regulation issues, further complicating daily life for these teens. 

Excessive screen time also stood out, with nearly two-thirds of teens with ADHD spending over four hours daily on screens, excluding schoolwork. This high screen usage is concerning, given its potential negative impact on physical and mental health, including sleep quality and social interactions. 

Notably, the study found no significant differences in physical activity levels or concerns about weight between teens with and without ADHD. This finding contrasts with previous studies that have highlighted lower physical activity among children with ADHD, suggesting the need for continued research on how physical activity is measured and encouraged in this population. 

The study’s authors emphasize the importance of health promotion interventions tailored specifically for teens with ADHD. By directly engaging teens and considering their unique perspectives, interventions can better address social-emotional well-being and healthy lifestyle behaviors, ultimately improving long-term outcomes for this vulnerable group. 

Overall, this research provides compelling evidence for healthcare providers, educators, and families to focus on supporting teens with ADHD in areas of social skills, sleep hygiene, and healthy screen time habits. Such targeted support can significantly enhance the quality of life and health outcomes for adolescents navigating the challenges of ADHD. 

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The Background on ADHD Treatments, rTMS and tDCS:

Methylphenidate is known as the gold-standard treatment for ADHD, increasing dopamine concentrations and helping to focus. However, these psychostimulants may be less well-tolerated in adults. Adverse effects include decreased appetite, nausea, racing heartbeat, restlessness, nervousness, and insomnia. 

Neurofeedback is a non-pharmaceutical treatment that combines cognitive behavioral therapy techniques like conditioning and positive reinforcement with electroencephalography (EEG) feedback. Electrodes are placed on specific brain areas, guiding patients to regulate their brainwave activity. 

Repetitive transcranial magnetic stimulation (rTMS) uses electromagnetism to induce an electric field by passing a magnetic field through the scalp. Transcranial direct current stimulation (tDCS), on the other hand, directly applies an electric current through the scalp. Both repetitive transcranial magnetic stimulation (rTMS) and tDCS primarily target the outermost layers of neurons, as they are non-invasive methods. Nevertheless, both techniques are believed to affect deeper layers through interconnected neuronal networks.  

The Study:

A French research team conducted a systematic search of the peer-reviewed medical literature to perform a meta-analysis to explore the efficacy of these experimental treatment techniques. 

Eight studies – four using rTMS and another four using tDCS – met the inclusion criteria. Studies had to be randomized controlled trials (RCTs), and had to involve multiple sessions of treatment. Participants had to be adults previously diagnosed with ADHD.  

Outcomes were measured through self-rated scales, neuropsychological tests, and electrophysiological pre-post evaluations. 

Separate meta-analyses of the four tDCS RCTs combining 154 participants and of the four rTMS RCTs encompassing 149 participants likewise reported no significant improvements. In all cases variation in outcomes between studies was moderate, and there were no signs of publication bias. 

The Conclusion on Neuromechanistic Treatments for ADHD:

Meta-analysis of all eight studies with a combined total of 421 participants reported no significant improvements over controls. Narrowing down to studies that used sham controls likewise produced no significant improvements. So, despite the title of this study, these neuromechanistic treatments do not appear to be the future of treatment for adult ADHD.

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According to the World Health Organization, suicide is the second leading cause of death among individuals aged 15 to 29 years. 

A European study team recently released findings of the first meta-analysis to explore the association between clinically diagnosed ADHD in children and adolescents and subsequent suicidality.  

The criteria for study inclusion were: 

• Most participants had to be under 18 at baseline. 

• Longitudinal design, meaning that participants were followed over time. 

• Having an ADHD sample diagnosed in childhood that was followed up for suicidal behavior. 

• Having a control group without ADHD that was followed up for suicidal behavior. 

• That ADHD was clinically diagnosed based on DSM-5 criteria. 

• The total number of participants and of those with suicidal behavior in both the ADHD group and the control group during follow-up were reported. 

All selected studies scored at least eight out of 11 points after quality assessment. The most frequent defect was that it was unclear whether suicidal behavior had occurred before study initiation. 

Meta-analysis of all nine included studies, encompassing more than 4.4 million participants, reported more than threefold greater odds of overall suicidal behavior among children and adolescents previously diagnosed with ADHD, as opposed to children and adolescents not previously diagnosed with ADHD. Study outcomes varied significantly (high heterogeneity) but showed no publication bias. 

Breaking this down into subcategories of risk: 

• Two studies combining 521 participants reported roughly fourfold greater odds of suicidal ideation among those previously diagnosed with ADHD, with negligible heterogeneity. 

• Six studies encompassing a total of more than 87,000 children and adolescents reported more than threefold greater odds of suicide attempt among those previously diagnosed with ADHD, with high heterogeneity. 

• Two studies combining more than 2.6 million participants reported a near-quadrupling of the odds of suicide death among those previously diagnosed with ADHD, with negligible heterogeneity. 

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The team concluded, “the current systematic review and meta-analysis has confirmed previous findings that there is an elevated risk for suicidal behavior in ADHD patients.” They also note, however, that “this relationship is heterogeneous and complex, with significant differences across ADHD subtypes, age groups, sexes, comorbidities, and social issues, all of which play important roles in the development of suicidal behavior.”

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