October 1, 2024
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.
.png)
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.
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.
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.
The study revealed that individuals with ADHD exhibit significantly different CA-scores in various brain regions compared to healthy controls. These regions include:
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.
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.
Maternal infections and inflammatory responses during pregnancy have been proposed as risk factors for neurodevelopmental disorders such as ADHD.
Taiwan has a single-payer health insurance system that covers virtually the entirety of its population. Its Ministry of Health and Welfare maintains the National Health Insurance Research Database (NHIRD), with detailed information on outpatient services, hospitalizations, and medical treatment for nearly 99% of all residents.
A Taiwanese study team used NHIRD to examine to examine the relationship between maternal hospitalization for infection, and early childhood infection, and subsequent ADHD in offspring. The study cohort originated with all 3,260,879 individuals born between 2001 and 2018.
The team excluded births from foreign mothers, still births, births with congenital defects, low birth weights, abnormally late births, twins, triplets, and other multiple births, culminating in a final population cohort of 2,885,662 live-born single infants across 1,893,171 families, and 1,864,660 individuals with full siblings from 872,169 families comprising the full sibling cohort.
Study participants were followed until diagnosis of a neurodevelopmental disorder, their death, or the end of 2021.
After adjusting for sex, birth year, paternal and maternal ages, birthweight, birth season, parity, delivery method, 1 minute APGAR score (evaluating baby’s appearance, pulse, grimace, activity and respiration at birth), gestational age, pregnancy and delivery complications, parental history of neurodevelopmental disorders, maternal asthma and diabetes, urbanization level of the residential area, and family’s insurance amount, offspring of mothers hospitalized for infections had 14% greater odds of being subsequently diagnosed with ADHD.
However, in the full sibling cohort of over 1.8 million, this association vanished. That held true for each of the three trimesters of pregnancy. It also held true for bacterial infections. Surprisingly, offspring of mothers hospitalized for viral infections were 24% less likely to be diagnosed with ADHD than their siblings not exposed to maternal viral infection. Because of that, they also had a 6% lower risk overall.
After the same adjustments, early childhood infection was associated with 16% greater odds of being diagnosed with ADHD.
Nevertheless, in the full sibling cohort of over 1.8 million, this association again vanished. That held true overall, as well as separately for childhood infections in months 1-6 and months 7-12. The association vanished altogether both for bacterial infections as well as for viral infections.
The authors concluded, “the results of this nationwide birth cohort study with population and sibling analyses suggest that the association between maternal infection during pregnancy and offspring neurodevelopmental risk is largely due to familial confounding factors.”
Most previous studies of suicide and self-harm risk among persons with ADHD have focused on adolescents and adults. They’ve also tended to be cross-sectional, analyzing data from a population at a specific point in time.
An Australian study team took a different approach, conducting a before-and-after study through the birth cohort of the Longitudinal Study of Australian Children (LSAC), comprising 5,107 children who have been followed up every two years since birth.
The diagnosis of ADHD was based on parents reporting that their child had received a diagnosis of ADHD at or before age ten.
Suicide and self-harm were defined as children’s self-report at age 14 of any thought or attempt of suicide and self-harm respectively over the past year.
The team adjusted for the following confounders: socioeconomic status, birth weight, ADHD medication history, maternal education level, maternal age at birth, experience in bullying victimization at age 12, and depression score based on Short Mood and Feelings Questionnaire (SMFQ).
Of the 5,107 participants, 3,696 had all the valid data required for analysis and were included in the final cohort. Of these, 3.6% were diagnosed with ADHD by age 10.
With diagnosis of ADHD at age 10 and all other factors held constant:
Both depression and exposure to bullying were statistically significant mediators for the relationship. Nevertheless, depression and exposure to bullying each accounted for well under 10% of the overall effect.
Neither socioeconomic status nor maternal factors had any significant mediating effect on outcomes.
Conclusion:
The authors concluded, “This study provides compelling evidence that children diagnosed with ADHD at the age of 10 years face significantly elevated risks of experiencing suicidal thoughts, planning, or attempts, as well as self-harm, by the age of 14 years, which underscores the critical importance of recognizing and addressing these heightened risks in children with ADHD.”
While factors like depression and bullying contribute, ADHD itself remains a key risk factor. Early intervention and strong mental health support are crucial to protecting these children’s well-being.
Noting that “Recent research has demonstrated that some gut bacteria can affect the nervous system,” and speculating that “dysregulation in the gut microbiota may increase the incidence of ADHD by overproducing reactive oxygen and nitrogen species, thereby causing neuroinflammation and oxidative stress”, a Taiwanese study team decided to explore whether early-life use of antibiotics – in the first two years – is associated with increased risk of subsequent diagnosis of ADHD.
Because Taiwan has a single-payer national health insurance system that covers 99.8% of the island’s population, they were able to use the system’s National Health Insurance Research Database (NHIRD) and Maternal and Child Health Database (TMCHD) to include all 1.6 million children born between 2004 and 2012.
Of these, a little over 1.1 million were given antibiotics before turning two years old, and just over 460,000 were not given antibiotics in the same time frame.
The mean follow-up period for records of subsequent ADHD diagnoses was seven years.
The team adjusted for confounding variables: sex, gestational age at birth (weeks), and birth weight (grams) of the children, and age at birth (years), insurance amount (New Taiwan Dollar (TWD)), insurance location, method of delivery, comorbidities, and medication used during pregnancy.
With these adjustments, early-life antibiotics use was associated with a 12% increase in likelihood of being subsequently diagnosed with ADHD.
However, looking at the effects of antibiotics as an undifferentiated grouping turned out to be misleading, because the association was limited to only some classes of antibiotics.
Penicillins were associated with a 22% increase in risk of subsequent ADHD diagnosis, cephalosporins with a 10% increase.
On the other hand, there was absolutely no such association for tetracyclines, macrolides, and quinolones.
The Take-Away:
This study found that children in Taiwan who took certain types of antibiotics before age 2 had a slightly higher risk of developing ADHD later in life. More work is needed to determine if this finding is due to unmeasured confounding before a causal link can be concluded.
_logo%201.svg)
