October 1, 2024

Understanding Hyperactivity in Women with ADHD: Absent or Hidden?

ADHD (Attention-Deficit/Hyperactivity Disorder) has often been seen as a condition that mainly affects boys, especially when it comes to hyperactivity. However, a new study challenges this idea by showing that hyperactivity is also common in women with ADHD, pointing out the need for better diagnoses.

The study included 13,179 adults with ADHD and 1,910 adults without it. Researchers measured how active participants were using a special test, looking at both "provoked" activity (activity triggered by specific tasks that puts the brain “online”) and "basal" activity (resting or natural activity levels when the brain is “offline”). The study included almost an equal number of men and women, with the goal of finding out if there were any differences between the sexes in ADHD diagnosis, particularly in hyperactivity.

The results were eye-opening. Although men generally showed higher levels of activity when the brain was online, both men and women with ADHD had much higher levels of both offline and online activity compared to people without ADHD. Specifically, those with ADHD had about twice the resting activity and three times the provoked activity compared to those without the disorder.

A key finding was that women with ADHD had hyperactivity levels similar to men with ADHD. This goes against the common belief that women with ADHD don’t show hyperactivity or show it less. It suggests that hyperactivity in women may be missed or misunderstood due to societal expectations or differences in behavior.

These findings have big implications. They suggest that the way we currently understand ADHD, especially hyperactivity in women, might be wrong. By recognizing that women with ADHD can have significant hyperactivity, doctors can diagnose ADHD more accurately. This could lead to earlier treatment and better management of ADHD in women, which might also lower the chances of related problems like anxiety or depression.

The study highlights the importance of thinking about gender differences when diagnosing and treating ADHD. By realizing that hyperactivity isn't just a "male" trait, we can better support everyone with ADHD and ensure they get the right care. As research on ADHD continues, it’s important to challenge old assumptions and take a more inclusive approach to understanding and treating the disorder.

Wettstein R, Navarro Ovando V, Pirgon E, Kroesen J, Wettstein K, Kroesen H, Mathôt R, Dumont G. Absent or Hidden? Hyperactivity in Females With ADHD. J Atten Disord. 2024 Aug 19:10870547241273152. doi: 10.1177/10870547241273152. Epub ahead of print. PMID: 39161237.

Related posts

News Tuesday: Fidgeting and ADHD

A recent study delved into the connection between fidgeting and cognitive performance in adults with Attention-Deficit/Hyperactivity Disorder. Recognizing that hyperactivity often manifests as fidgeting, the researchers sought to understand its role in attention and performance during cognitively demanding tasks. They designed a framework to quantify meaningful fidgeting variables using actigraphy devices.

(Note: Actigraphy is a non-invasive method of monitoring human rest/activity cycles. It involves the use of a small, wearable device called an actigraph or actimetry sensor, typically worn on the wrist, similar to a watch. The actigraph records movement data over extended periods, often days to weeks, to track sleep patterns, activity levels, and circadian rhythms. In this study, actigraphy devices were used to measure fidgeting by recording the participants' movements continuously during the cognitive task. This data provided objective, quantitative measures of fidgeting, allowing the researchers to analyze its relationship with attention and task performance.)

The study involved 70 adult participants aged 18-50, all diagnosed with ADHD. Participants underwent a thorough screening process, including clinical interviews and ADHD symptom ratings. The analysis revealed that fidgeting increased during correct trials, particularly in participants with consistent reaction times, suggesting that fidgeting helps sustain attention. Interestingly, fidgeting patterns varied between early and later trials, further highlighting its role in maintaining focus over time.

Additionally, a correlation analysis validated the relevance of the newly defined fidget variables with ADHD symptom severity. This finding suggests that fidgeting may act as a compensatory mechanism for individuals with ADHD, aiding in their ability to maintain attention during tasks requiring cognitive control.

This study provides valuable insights into the role of fidgeting in adults with ADHD, suggesting that it may help sustain attention during challenging cognitive tasks. By introducing and validating new fidget variables, the researchers hope to standardize future quantitative research in this area. Understanding the compensatory role of fidgeting can lead to better management strategies for ADHD, emphasizing the potential benefits of movement for maintaining focus.

July 16, 2024

NEWS TUESDAY: Controllability in ADHD

Recent advancements in brain network analysis may help researchers better understand the dysfunctions of the complex neural networks associated with ADHD.

Controllability refers to the ability to steer the brain's activity from one state to another. In simpler terms, it’s about how different regions of the brain can influence and regulate each other to maintain normal functioning or respond to tasks and stimuli. 

The Study at a Glance

Researchers examined functional MRI (fMRI) data from 143 healthy individuals and 102 ADHD patients, they focused on a specific metric called the node controllability index (CA-scores). This metric helps quantify how different brain regions contribute to overall brain function.

Key Findings

The study revealed that individuals with ADHD exhibit significantly different CA-scores in various brain regions compared to healthy controls. These regions include:

  • Rolandic operculum
  • Superior medial orbitofrontal cortex
  • Insula
  • Posterior cingulate gyrus
  • Supramarginal gyrus
  • Angular gyrus
  • Precuneus
  • Heschl gyrus
  • Superior temporal gyrus

These areas are crucial for processes such as decision-making, sensory processing, and attention.

This new study suggests that the controllability index might be a more effective tool in identifying brain regions that work differently in those with ADHD. This means that controllability could provide a clearer picture of the brain networks associated with ADHD.

Although ADHD still cannot be diagnosed with this type of imaging, studies such as this highlight the complexity of the disorder and provide new avenues for future research. 

August 6, 2024

Non-stimulant Medications for Adults with ADHD: An Overview

NEW STUDY: Non-stimulant Medications for Adults with ADHD: An Overview

Attention-Deficit/Hyperactivity Disorder (ADHD) in adults is commonly treated with stimulant medications such as methylphenidate and amphetamines. However, not all patients respond well to these stimulants or tolerate them effectively. For such cases, non-stimulant medications provide an alternative treatment approach.

Recent research by Brancati et al. reviews the efficacy and safety of non-stimulant medications for adult ADHD. Atomoxetine, a well-studied non-stimulant, has shown significant effectiveness in treating ADHD symptoms in adults. The review highlights the importance of considering dosage, treatment duration, safety, and the presence of psychiatric comorbidities when prescribing atomoxetine.

Additionally, certain antidepressants, including tricyclic compounds, bupropion, and viloxazine, which possess noradrenergic or dopaminergic properties, have demonstrated efficacy in managing adult ADHD. Antihypertensive medications, especially guanfacine, have also been found effective. Other medications like memantine, metadoxine, and mood stabilizers show promise, whereas treatments like galantamine, antipsychotics, and cannabinoids have not yielded positive results.

The expert opinion section of the review emphasizes that while clinical guidelines primarily recommend atomoxetine as a second-line treatment, several other non-stimulant options can be utilized to tailor treatments based on individual patient needs and comorbid conditions. Despite these advancements, the authors call for further research to develop and refine more personalized treatment strategies for adults with ADHD.

This review underscores the growing landscape of non-stimulant treatment options, offering hope for more personalized and effective management of ADHD in adults.

June 25, 2024

NEW STUDY: Understanding the Gap Between ADHD Clinical Trials and Real-World Patients

Background 

ADHD (Attention-Deficit/Hyperactivity Disorder) is one of the most studied neurodevelopmental conditions, with many clinical trials evaluating the effectiveness and safety of various medications. These trials, known as randomized controlled trials (RCTs), are considered the gold standard for assessing treatments. However, strict eligibility criteria often exclude many real-world patients, raising questions about whether the findings from these trials apply to everyday clinical settings.

Our latest study sheds light on this issue, revealing just how many individuals with ADHD might be excluded from RCTs and the impact this exclusion has on their treatment outcomes. 

Method

Researchers used Swedish national registries to analyze data from 189,699 individuals diagnosed with ADHD who started medication between 2007 and 2019. They applied exclusion criteria from 164 international RCTs to identify who would have been considered ineligible for these trials in order to determine the proportion of individuals with ADHD who would not meet the eligibility criteria for RCTs.  

Key Findings

Many Patients Are Ineligible for Clinical Trials:

  • Over half (53%) of the study population would have been ineligible for ADHD medication trials.
  • Adults were most likely to be excluded (74%), followed by adolescents (35%) and children (21%).

Ineligible Patients Face Unique Challenges:

  • Treatment Switching: Ineligible individuals were more likely to switch medications within the first year (14% higher likelihood compared to eligible patients).
  • Medication Discontinuation: They were slightly less likely to stop taking their medication during the first year.

Higher Risk of Adverse Outcomes:

  • Ineligible patients experienced significantly higher rates of psychiatric hospitalizations and health issues such as depression, anxiety, and substance use disorders. For instance:some text
    • Psychiatric hospitalizations: Nearly 10 times more likely.
    • Specialist visits for substance use disorders: About 15 times more likely.
    • Anxiety-related visits: Over 11 times more likely.

What This Means

These findings highlight a major gap between the controlled environments of clinical trials and the realities faced by individuals with ADHD in everyday life. While RCTs provide valuable insights, their restrictive criteria often exclude patients with more complex health profiles or co-existing conditions. This limits the generalisability of trial results, meaning that treatment guidelines based solely on RCTs may not fully address the needs of all patients.

Conclusion

This study demonstrated that a significant proportion of individuals with ADHD, particularly adults, do not meet the eligibility criteria for standard RCTs. These results emphasize the importance of bridging the gap between research settings and real-world applications. By recognizing and addressing the limitations of RCTs, we can work towards more equitable and effective ADHD treatment strategies for everyone.

January 14, 2025

Where Does ADHD Fit in the Psychopathology Hierarchy? A Symptom-Focused Study

NEWS TUESDAY: Where Does ADHD Fit in the Psychopathology Hierarchy? A Symptom-Focused Study

Background:

Our understanding of Attention-deficit/hyperactivity disorder (ADHD) has grown and evolved considerably since it first appeared in the DSM-II as “Hyperkinetic Reaction of Childhood.”  This study aimed to find the disorder’s placement within the modern psychopathology classification systems like the Hierarchical Taxonomy Of Psychopathology (HiTOP). 

The HiTOP model aims to address limitations of traditional classification systems for mental illness, such as the DSM-5 and ICD-10, by organizing psychopathology according to evidence from research on observable patterns of mental health problems.. Is ADHD best categorized under externalizing conditions, neurodevelopmental disorders, or something else entirely? A recent study by Zheyue Peng, Kasey Stanton, Beatriz Dominguez-Alvarez, and Ashley L. Watts takes a closer look at this question using a symptom-focused approach.

The Study:

Traditionally, ADHD has been associated with externalizing behaviors, such as impulsivity and hyperactivity, or with neurodevelopmental traits, like cognitive delays. However, this study challenges the idea of placing ADHD into a single category. Instead, it maps ADHD symptoms across three major psychopathology spectra: externalizing, neurodevelopmental, and internalizing.

The findings reveal that ADHD symptoms don’t fit neatly into one box. For example, symptoms like impulsivity, poor school performance, and low perseverance were strongly associated with externalizing behaviors. On the other hand, cognitive disengagement (e.g., daydreaming, blank staring) and immaturity were closely linked to neurodevelopmental challenges. Interestingly, cognitive disengagement also showed ties to internalizing symptoms, such as anxiety or depression.

This research underscores the complexity of ADHD. Rather than treating ADHD as a single, unitary construct, the study advocates for a symptom-based approach to better understand and treat individuals. By acknowledging that ADHD symptoms relate to multiple psychopathology spectra, clinicians and researchers can move toward more nuanced classification systems and targeted interventions.

Conclusion: 

Ultimately, this study highlights the need for modern systems to move beyond rigid categories and adopt a more flexible, symptom-focused framework for understanding ADHD’s place in psychopathology.

January 6, 2025

Meta-analyses Find Dose-response Association Between Lead Exposure and Subsequent ADHD

Meta-analyses Find Dose-response Association Between Lead Exposure and Subsequent ADHD

Background:

Exposure to heavy metals like lead, arsenic, mercury, cadmium, and manganese is known to harm developing nervous systems. However, past studies on whether heavy metals specifically increase the risk of ADHD have shown mixed results.

A research team from China (Gu et al., 2024) reviewed medical studies and conducted meta-analyses to better understand this issue.

Methods:

The team included studies on children and teens, focusing on cohort studies, case-control studies, and cross-sectional studies. They only used articles written in English and required validated biomonitoring (like blood tests) to measure heavy metal exposure. ADHD diagnoses had to come from clinical evaluations.

To be included, studies had to report effect sizes such as odds ratios and relative risks with confidence intervals. The team focused on comparisons between groups with high, low, or no exposure, which made it harder to analyze dose-response relationships.

They also evaluated the quality of each study. All cohort studies were rated high-quality. Of the 15 case-control studies, 6 were high-quality, and 9 were moderate-quality. Among cross-sectional studies, only 2 were high-quality, and the rest were moderate-quality.

Key Findings:
  1. Lead Exposure and ADHD:some text
    • A meta-analysis of 22 studies with over 20,000 participants found that early exposure to lead was linked to about twice the odds of an ADHD diagnosis compared to unexposed children.
    • However, results varied widely among studies, and signs of publication bias were detected. After adjusting for this bias, the increased odds dropped to about 50%.
    • A dose-response relationship was found:some text
      • Blood lead levels of 2.5 µg/dL increased ADHD risk by 1.8 times.
      • Levels of 5 µg/dL increased the risk 2.5 times.
      • Levels of 7.5 µg/dL increased the risk 2.75 times.
      • Levels of 10 µg/dL tripled the risk.
  2. Other Metals:some text
    • No significant links were found between ADHD and exposure to arsenic, mercury, cadmium, or manganese. Fewer studies were available for these metals, and participant numbers were much smaller:some text
      • Arsenic exposure: 25% higher odds of ADHD (4 studies, 3,116 participants).
      • Mercury exposure: 25% higher odds (6 studies, 2,916 participants).
      • Cadmium exposure: 25% higher odds (5 studies, 2,419 participants).
      • Manganese exposure: 45% higher odds (6 studies, 1,664 participants).
  3. Austrian Study: An Austrian team (Rosenauer et al., 2024) also conducted a meta-analysis on lead exposure and ADHD. They included 14 studies with over 7,600 participants and found:some text
    • Lead exposure increased the odds of ADHD by about 25%.
    • Studies focusing on higher lead levels found a 43% increased risk, supporting a dose-response relationship.
    • Study results were consistent, with no signs of publication bias.
Conclusion:

There was no evidence linking ADHD to other heavy metals like arsenic, mercury, cadmium, or manganese.  Both meta-analyses suggest that lead exposure is associated with the risk for ADHD.  However, because these studies cannot rule out other explanations, one cannot conclude that lead exposure causes ADHD.  For example, other work shows that people with ADHD are likely to have lower incomes than those without ADHD.  

January 17, 2025