April 13, 2021
In the world of research, it is unusual for a single study to be definitive. A possible exception is a recent report in the highly esteemed Lancet, which concluded that people diagnosed with ADHD were about two times more likely to die early than people without ADHD. The data came from the medical registers of Denmark that include1.92 a million people, of which 32,061 have ADHD. The registers included the times and causes of deaths spanning 32 years.
It is a remarkable resource. We know that people with very severe ADHD are at high risk for substance use disorders and antisocial behaviors. In the Danish study, these disorders also increased the risk for premature death, but the risk was even higher if people with those disorders also had ADHD. ADHD also increased the risk for early death among people without these extra problems. This latter finding points to an ADHD-specific pathway to premature death. What is it? Well, we know that ADHD people are at risk for injuries, traffic accidents, and traumatic brain injury. We don't know for certain why, but two symptom clusters of ADHD, inattention, and impulsivity, would be expected to increase the risk for accidents and injuries. For example, adults who are distracted while driving are clearly at risk for accidents. Accidents accounted for most of the early deaths in the Danish study. But the study also found an increase in natural causes of death due to having ADHD. This may be due to the well-replicated association between ADHD and obesity, or the possibility that ADHD symptoms lead to poor health habits.
In the Danish study, the mean age at diagnosis was 12.3, which means that many of the ADHD people in the study were not treated for many years after the onset of symptoms. The risk for early death increased with the age at diagnosis. This suggests that failing to diagnose and treat ADHD early makes the disorder worse and increases the risk for the types of behaviors that lead to premature death. Will these data change public policy or clinician behavior? I hope so. Perhaps the media will stop trivializing ADHD and accept it as a bona fide disorder in need of early identification and treatment. Policymakers should allocate ADHD people their fair share of healthcare and research resources. For clinicians, early identification and treatment should become the rule rather than the exception.
Talk of premature death will worry parents and patients. That is understandable, but such worries can be alleviated by focusing on two facts: the absolute risk for premature death is low, and this risk can be greatly reduced by seeking and adhering to evidence-based treatments for the disorder.
Dalsgaard, S., Ostergaard, S. D., Leckman, J. F., Mortensen,P. B. & Pedersen, M. G. (2015). Mortality in children, adolescents, andadults with attention deficit hyperactivity disorder: a nationwide cohortstudy. Lancet.
Vaa T. ADHD and relative risk of accidents in road traffic:a meta-analysis. Accident; analysis and prevention.2014; 62: 415-25.
Adeyemo BO,Biederman J, Zafonte R, Kagan E, Spencer TJ, Uchida M, et al. MildTraumatic Brain Injury and ADHD: A Systematic Review of the Literature andMeta-Analysis. J AttenDisord. 2014; 18(7): 576-84.
Cortese S, Faraone SV, Bernardi S, Wang S, Blanco C. Adultattention-deficit hyperactivity disorder and obesity: epidemiological study. BrJ Psychiatry.2013; 203: 24-34.
Spencer TS, Faraone SV, Tarko L, McDermott K, Biederman J.ADHD and Adverse Health Outcomes in Adults: Results from a Large ControlledStudy. 2013.
Faraone SV. The scientific foundation for understandingattention-deficit/hyperactivity disorder as a valid psychiatric disorder.EurChild Adolesc Psychiatry.2005; 14: 1-10."
Adult ADHD has long been a subject of debate in the field of mental health, with previous estimates of its prevalence varying widely. To achieve a more precise understanding, an international team of researchers conducted a new umbrella review and meta-analysis, offering an updated estimate of adult ADHD rates worldwide.
This large-scale analysis combined five systematic reviews and meta-analyses, incorporating data from 57 unique primary studies. Altogether, the research synthesized findings from a pooled total of over 21 million participants. This comprehensive approach provided a more accurate estimate of the global prevalence of ADHD in adults.
The study concluded that the worldwide prevalence of adult ADHD is 3.1%, with a 95% confidence interval ranging from 2.6% to 3.6%. This estimate falls within the range of earlier reports but provides a more targeted understanding of the rate at which ADHD affects adults globally.
The researchers described this prevalence rate as “relatively high.” They noted that it is only slightly lower than the estimated prevalence of major mental health conditions like schizophrenia (4%) and major depressive disorder (5%)—disorders that have historically received significant attention and resources worldwide.
Moreover, the prevalence of adult ADHD is higher than that of several other well-known mental health conditions, including bipolar disorder (1%), as well as anxiety disorders such as PTSD (Post-Traumatic Stress Disorder), OCD (Obsessive-Compulsive Disorder), GAD (Generalized Anxiety Disorder), and panic disorders.
This updated estimate emphasizes that ADHD is a significant global mental health concern in adults, comparable to or exceeding the prevalence of other disorders that are often more widely recognized. These findings underscore the need for greater awareness, research, and treatment options for adult ADHD, which is still frequently misunderstood or overlooked in the broader discourse of mental health.
By providing a clearer picture of how prevalent ADHD is in adult populations around the world, this study contributes valuable data that could shape future research, policy, and clinical approaches.
Attention-Deficit/Hyperactivity Disorder (ADHD) remains a prevalent condition among children and adolescents in the United States. A recent analysis based on the National Health Interview Survey (NHIS), conducted by the National Center for Health Statistics at the CDC, provides an updated look at ADHD prevalence from 2018 to 2021. Here’s a closer look at what the data reveals.
The NHIS is an annual survey primarily conducted through face-to-face interviews in respondents’ homes. Telephone interviews are used as a substitute in cases where travel is impractical. For each family interviewed, one child aged 3-17 is randomly selected for the survey through a computer program. Over the four years studied (2018-2021), a total of 26,422 households with children or adolescents participated.
The analysis found that 9.5% of children and adolescents in the United States had been diagnosed with ADHD, based on reports from family members. However, the prevalence varied significantly with age:
The increase in ADHD diagnosis with age underscores the importance of monitoring children’s developmental needs as they progress through school and adolescence.
The survey revealed a notable difference in ADHD prevalence between genders, with 12.4% of males diagnosed compared to 6.6% of females—nearly a two-to-one gap. This aligns with previous research indicating that ADHD is more frequently diagnosed in boys than girls, though awareness of how ADHD presents differently across genders is growing.
Family income played a significant role in ADHD prevalence, particularly among lower-income groups:
This pattern suggests that socioeconomic factors might influence the diagnosis and management of ADHD, with lower-income families possibly experiencing greater barriers to early diagnosis or consistent treatment.
Geographic location also impacted ADHD rates. Prevalence was highest in the South (11.3%), followed by the Midwest (10%), the Northeast (9.1%), and significantly lower in the West (6.9%). These variations could reflect regional differences in healthcare access, diagnostic practices, or cultural attitudes towards ADHD.
Despite these variations in demographics, the overall prevalence of ADHD remained relatively stable across the study period from 2018 to 2021, showing no significant changes by year.
The findings from this updated analysis provide a clearer picture of ADHD’s prevalence across different demographic groups in the United States. They highlight the need for tailored approaches to diagnosis and care, taking into account factors like age, gender, income, and geographic location. With ADHD being a common condition affecting nearly 1 in 10 children, ongoing research and support for families are crucial to ensure that those with ADHD receive the care and resources they need.
This study reinforces the importance of awareness and early intervention, especially for families in underserved regions or those facing economic challenges. As clinicians and educators continue to support children with ADHD, understanding these demographic trends can help in creating more equitable access to diagnosis and treatment.
Stimulant medications like methylphenidate and amphetamines are well-established treatments for reducing ADHD symptoms, making a notable difference in focus and behavior. Given that caffeine is also a stimulant, researchers have wondered whether it might offer similar benefits for managing ADHD symptoms. A recent meta-analysis conducted by a Brazilian research team sought to explore this question.
The researchers faced an immediate challenge: there is surprisingly little research directly investigating caffeine's effects on ADHD symptoms. After a thorough review of peer-reviewed literature, they identified only four randomized controlled trials (RCTs) suitable for their analysis, encompassing a combined total of just 152 participants.
The limited number of studies—and participants—meant that the meta-analysis was not as robust as the research team might have hoped. However, they proceeded to examine the available data to determine whether caffeine showed any measurable benefit over a placebo.
The results of the meta-analysis showed a slight decrease in ADHD symptoms among those who consumed caffeine compared to those given a placebo. However, this reduction was not statistically significant. The small sample size likely played a role in this outcome, making the study underpowered. Even if future studies with larger groups of participants were to show statistical significance, the observed effect size would likely remain too small to be clinically meaningful.
Interestingly, the four trials included in the meta-analysis showed very little variation in their findings. Each study slightly favored caffeine over placebo, but none came close to achieving statistical significance.
Ultimately, the researchers concluded that “overall, the totality of the evidence suggests no significant benefit of caffeine over placebo in the treatment of children with ADHD.” The findings indicate that while caffeine might produce a slight reduction in symptoms, it is not an effective alternative to established ADHD treatments like methylphenidate or amphetamines.
This study highlights the importance of relying on proven medications for ADHD management rather than seeking alternatives that lack substantial evidence. While caffeine might offer a slight stimulant effect, it falls short of delivering the therapeutic benefits needed for those with ADHD to manage their symptoms effectively. For clinicians, parents, and individuals with ADHD, these results underscore the value of evidence-based treatments in improving quality of life and daily functioning.
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