http://medicalwritingtraining.com/ADHD is a serious disorder that requires treatment to prevent many adverse outcomes. But, because the diagnosis of ADHD is based on how the patient responds to questions, it is possible for people to pretend that they have ADHD, when they do not. In fact, if you Google “fake ADHD” you’ll get many pages of links including a Psychology Today article on the topic and bloggers describing how they were able to fool doctors into giving them ADHD medications. Is fake ADHD a serious problem? Not really.

The Internet, it seems, is faking an epidemic of fake ADHD. I say that because we have decades of research that show many objective measures of abnormality and impairment in people who say they have ADHD. These include traffic accidents, abnormalities on brain imaging and molecular genetic differences. Some studies even suggest that ADHD adults downplay their ADHD symptoms. For example, one study diagnosed ADHD in children and then contacted them many years later when they were young adults. When they were interviewed as young adults, their responses to questions about ADHD suggested that they did not have the disorder. But when the same questions about the patient were asked to someone who lived with the patient as a young adult, it was clear that they still had ADHD. So rather than faking ADHD, many ADHD adults do not recognize that they have symptoms of the disorder.

That said, we also know from research studies that, when asked to pretend that they have ADHD, adults can fake the disorder. That means that they can learn about the symptoms of the disorder and make up examples of how they have had them, when they have not. This research suggests that this is not common, but we do know that some people have motives for faking ADHD. For example, some college students seek special accommodations for taking tests; others may want stimulants for abuse, misuse or diversion.

Fortunately, doctors can detect fake ADHD in several ways. If an adult is self-referred for ADHD and asks specifically for stimulant medication, that raises the possibility of fake ADHD and drug seeking. Because the issue of stimulant misuse has been mostly a concern on college campuses, many doctors treating college students will require independent verification of the patients ADHD symptoms by speaking with a parent, even over the phone if an in-person visit is not possible. Using ADHD rating scales will not detect fake ADHD and it is easy to fake poor performance on tests of reading or math ability. Neuropsychological tests can sometimes be used to detect malingering but require referral to a specialist. Researchers are developing methods to detect faking of ADHD symptoms. These have shown some utility in studies of young adults but are not ready for clinical practice.

So, currently, doctors concerned about fake ADHD should look for objective indicators of impairment (e.g., documented traffic accidents; academic performance below expectation) and speak to a parent of the patient to document that impairing symptoms of the disorder were present before the age of twelve. Because the issue of fake ADHD is of most concern on college campuses, it can also be helpful to speak with a teacher who has had frequent contact with the patient. In an era of large lecture halls and broadcast lectures, that may be difficult. And don’t be fooled by the Internet. We don’t want to deny treatment to ADHD patients out of undocumented reports of an epidemic of fake ADHD.
The best way for health professionals to determine if someone has ADHD by the way, is by performing a complete diagnosis. We teach that in our FREE online CME courses on ADHD in Adults.
 

References:
Harrison, A. G., Edwards, M. J. & Parker, K. C. (2007). Identifying students faking ADHD: Preliminary findings and strategies for detection. Arch Clin Neuropsychol 22, 577-88.
Sansone, R. A. & Sansone, L. A. (2011). Faking attention deficit hyperactivity disorder. Innov Clin Neurosci 8, 10-3.
Loughan, A., Perna, R., Le, J. & Hertza, J. (2014). C-88Abbreviating the Test of Memory Malingering: TOMM Trial 1 in Children with ADHD. Arch Clin Neuropsychol 29, 605-6.
Loughan, A. R. & Perna, R. (2014). Performance and specificity rates in the Test of Memory Malingering: an investigation into pediatric clinical populations. Appl Neuropsychol Child 3, 26-30.
Quinn, C. A. (2003). Detection of malingering in assessment of adult ADHD. Arch Clin Neuropsychol 18, 379-95.
Suhr, J., Hammers, D., Dobbins-Buckland, K., Zimak, E. & Hughes, C. (2008). The relationship of malingering test failure to self-reported symptoms and neuropsychological findings in adults referred for ADHD evaluation. Arch Clin Neuropsychol 23, 521-30.
Greve, K. W. & Bianchini, K. J. (2002). Using the Wisconsin card sorting test to detect malingering: an analysis of the specificity of two methods in nonmalingering normal and patient samples. J Clin Exp Neuropsychol 24, 48-54.
Killgore, W. D. & DellaPietra, L. (2000). Using the WMS-III to detect malingering: empirical validation of the rarely missed index (RMI). J Clin Exp Neuropsychol 22, 761-71.
Ord, J. S., Greve, K. W. & Bianchini, K. J. (2008). Using the Wechsler Memory Scale-III to detect malingering in mild traumatic brain injury. Clin Neuropsychol 22, 689-704.
Wisdom, N. M., Callahan, J. L. & Shaw, T. G. (2010). Diagnostic utility of the structured inventory of malingered symptomatology to detect malingering in a forensic sample. Arch Clin Neuropsychol 25, 118-25.

http://medicalwritingtraining.com/Many myths have been manufactured about attention deficit hyperactivity disorder (ADHD).  Facts that are clear and compelling to most scientists and doctors have been distorted or discarded from popular media discussions of the disorder.   Sometimes, the popular media seems motivated by the maxim “Never let the facts get in the way of a good story.”  That’s fine for storytellers, but it is not acceptable for serious and useful discussions about ADHD.

Myths about ADHD are easy to find.  These myths have confused patients and parents and undermined the ability for professionals to appropriately treat the disorder.   When patients or parents get the idea that the diagnosis of ADHD is a subjective invention of doctors, or that ADHD medications cause drug abuse, that makes it less likely they will seek treatment and will increase their chances of having adverse outcomes.

Fortunately, as John Adams famously said of the Boston Massacre, “Facts are stubborn things.”  And science is a stubborn enterprise; it does not tolerate shoddy research or opinions not supported by fact.   ADHD scientists have addressed many of the myths about the disorder in the International Consensus Statement on ADHD, a published summary of scientific facts about ADHD endorsed by a of 75 international ADHD scientists in 2002.  The statement describes evidence for the validity of ADHD, the existence of genetic and neurobiologic causes for the disorder and the range and severity of impairments caused by the disorder.The

Statement makes several key points:

  • The U.S. Surgeon General, the American Medical Association, the American Psychiatric Association, the American Academy of Child and Adolescent Psychiatry, the American Psychological Association, and the American Academy of Pediatrics recognize ADHD as a valid disorder.
  • ADHD involves a serious deficiency in a set of psychological abilities and that these deficiencies pose serious harm to most individuals possessing the disorder.
  • Many studies show that the psychological deficits in people with ADHD are associated with abnormalities in several specific brain regions.
  • The genetic contribution to ADHD is routinely found to be among the highest for any psychiatric disorders.
  • ADHD is not a benign disorder. For those it afflicts, it can cause devastating problems.

The facts about ADHD will prevail if you take the time to learn about them.   This can be difficult when faced with a media blitz of information and misinformation about the disorder.  In future blogs, I’ll separate the fact from the fiction by addressing several popular myths about ADHD.

 

http://medicalwritingtraining.com/Cognitive Behavioral Therapy (CBT) is a one to one therapy, for adolescents or adults, where a therapist teaches an ADHD patient how thoughts, feelings, and behaviors are all interrelated and how each of these elements affects the others. CBT emphasizes cognition, or thinking, because a major goal of this therapy is to help patients identifying thinking patterns that lead to problem behaviors. For example, the therapist might discover that the patient frequently has negative automatic thoughts such as “I’m stupid” in challenging situations. We call the though ‘automatic’ because it invades the patients consciousness without any effort. Thinking “I’m stupid” can cause anxiety and depression which leads to failure. Thus, stopping the automatic thought will modify this chain of events and, hopefully, improve the outcome from failure to success.

CBT also educates patients about their ADHD and how it affects them in important daily activities. For example, most ADHD patients need help with activity scheduling, socializing, organizing their workspace and controlling their distractibility. By teaching specific cognitive and behavioral skills, the therapist helps the patient deal with their ADHD symptoms in a productive manner. For example, some ADHD patients are very impulsive when conversing with others. They don’t wait their turn during conversations and may blurt out irrelevant idea. This can be annoying to others, especially in the context of school or business relationships. The CBT therapist helps the patient identify these behaviors and creates strategies for avoiding them.

So, does CBT work for ADHD? The evidence base is small, but when CBT has been used for adult ADHD, it has produced positive results in well-designed studies. These studies typically compare patients taking ADHD medications with those taking ADHD medications and receiving CBT. So for now, it is best to consider CBT as an adjunct to rather than a replacement for medication. There are even fewer studies of CBT for adolescents for ADHD. These initial studies also suggest that CBT will be useful for adolescents with ADHD who are also taking ADHD medications. Some data suggest that CBT can be successfully applied in the classroom environment but, again, the evidence base is very small.

How can this information be used by doctors and patients for treatment planning? Current treatment guidelines suggest starting with an ADHD medication. After a suitable medication and dose is found, the patient and doctor should determine if any problems remain. If so, than CBT should be considered as an adjunct to ADHD medications.
 

References:
Antshel, K. M. & Olszewski, A. K. (2014). Cognitive Behavioral Therapy for Adolescents with ADHD. Child Adolesc Psychiatr Clin N Am 23, 825-842.
Safren, S. A., Sprich, S., Mimiaga, M. J., Surman, C., Knouse, L., Groves, M. & Otto, M. W. (2010). Cognitive behavioral therapy vs relaxation with educational support for medication-treated adults with ADHD and persistent symptoms: a randomized controlled trial. JAMA 304, 875-80.
Solanto, M. V., Marks, D. J., Wasserstein, J., Mitchell, K., Abikoff, H., Alvir, J. M. & Kofman, M. D. (2010). Efficacy of meta-cognitive therapy for adult ADHD. Am J Psychiatry 167, 958-68.

http://medicalwritingtraining.com/The stimulants methylphenidate and amphetamine are well known for their efficacy in treating symptoms of ADHD in both youth and adults. Although these medications have been used for several decade, relatively little is known about the mechanisms of action that lead to their therapeutic effect. New data about mechanism comes from a meta-analysis by Katya Rubia and colleagues. They analyzed 14 functional magnetic resonance imaging (fMRI) data sets comprising 212 youth with ADHD. Each of these data sets assessed the short term effects of stimulants on fMRI assessed brain activations. In the fMRI paradigm, ADHD and control participants are asked to do a neurocognitive task while the activity of their brains is being measured. Dr. Rubia and colleagues analyzed data from fMRI assessments of time discrimination, inhibition and working memory, each of which are known to be deficient in ADHD patients. The meta-analysis found that the most consistent brain activations were seen in a region comprising the right inferior frontal cortex (IFC) and insula, even when the analysis was limited to previously medication naïve patients. The implicated region of the brain is known to mediate cognitive control, time estimation and attention. Dr. Rubia also notes that other studies show that the IFC/Insula is needed for updating information and allocating attention to relevant stimuli. Another region implicate by the meta-analysis was the right putamen, a region that is rich in dopamine transporters. This finding is consistent with the fact that the dopamine transporter is the main target of stimulant medications. What are the potential clinical implication of these findings? As Dr. Rubia and colleagues note, it is possible that the fMRI anomalies they identified could be used as a biomarker for ADHD or a biomarker to select patients who should respond optimally to stimulant medication. Although fMRI cannot be used as a clinical tool at this time, research of this sort is opening up new horizons for how we understand the etiology of ADHD and the mechanisms whereby medications exert their effects.
 

Reference
Rubia, K., Alegria, A. A., Cubillo, A. I., Smith, A. B., Brammer, M. J. & Radua, J. (2014). Effects of stimulants on brain function in attention-deficit/hyperactivity disorder: a systematic review and meta-analysis. Biol Psychiatry 76, 616-28.

http://medicalwritingtraining.com/A recent paper by Margaret Sibley and colleagues addresses a key issue in the diagnosis of adult ADHD. Is it sufficient to only collect data from the patient being diagnosed or are informants useful or, perhaps, essential, for diagnosing ADHD in adults. Dr. Sibley presented as systematic review of twelve studies that prospectively followed ADHD children into adulthood. Each of these studies asked a simple question: What faction of ADHD youth continued to have ADHD in adulthood. Surprisingly, the estimates of ADHD’s persistence ranged from a low of 4% to a high of 77%. They found two study features that accounted for much of this wide range. The first was the nature of the informant; did the study rely only on the patient’s report or were other informants consulted. The second was the use of a strict diagnostic threshold of six symptoms. When they limited the analysis to studies that used informant and eliminated the six symptom threshold, the range of estimates was much narrower, 40% to 77%. From studies that computed multiple measures of persistence using different criteria, the authors concluded: “(1) requiring impairment to be present for diagnosis reduced persistence rates; (2) a norm-based symptom threshold led to higher persistence than a strict six-symptom DSM-based symptom count criterion; and (3) informant reports tended to show a higher number of symptoms than self-reports.” These data have clear implications for what clinicians can do to avoid false positive and false negative diagnoses when diagnosing adult ADHD. It is reassuring that the self-reports of ADHD patients tend to underestimate the number and severity of ADHD symptoms. This means that your patients are not typically exaggerating their symptoms. Put differently, self-reports will not lead you to over-diagnose adult ADHD. Instead, reliance on self-reports can lead to false negative diagnoses, i.e., concluding that someone does not have ADHD when, in fact, they do. You can avoid false negatives by doing a thorough assessment, which is facilitated by some tools available at www.adhdinadults.com and described in CME videos there. If you think a patient might have ADHD but are not certain, it would be helpful to collect data from an informant, i.e., someone who knows the patient well such as a spouse, partner, roommate or parent. You can collect such data by sending home a rating scale or by having the patient bring an informant to a subsequent visit. Dr. Sibley’s paper also shows that you can avoid false negative diagnoses by using a lower symptom threshold than what is required in the diagnostic manual. In fact, the new DSM 5 lowered the symptom threshold for adults from six to five. Can you go lower? Yes, but it is essential to show that these symptoms lead to clear impairments in living. Importantly, this symptom threshold refers to the number of symptoms documented in adulthood, not to the number of symptoms retrospectively reported in childhood. To be diagnosed with ADHD in adulthood, one must document that the patient had at least six impairing symptoms of ADHD prior to the age of 12.
 

REFERENCE
Sibley, M. H., Mitchell, J. T. & Becker, S. P. (2016). Method of adult diagnosis influences estimated persistence of childhood ADHD: a systematic review of longitudinal studies. Lancet Psychiatry 3, 1157-1165.

http://medicalwritingtraining.com/The term “cognitive behavior therapy (CBT)” refers to a type of talk therapy that seeks to change the way patients think about themselves, their disorder and the world around them in a manner that will help them overcome symptoms and achieve life goals. Because CBT is typically administered by a psychologist or other mental health professionals, CBT services are not available in primary care. Nonetheless, it is useful for primary care practitioners to know about CBT so that they can refer appropriately as needed. So, what can we say about the efficacy of CBT for treating adults with ADHD. Based on a meta-analysis by Young and colleagues, we know for certain that the number of published trials of CBT for adult ADHD is small; only nine trials are available. Five of these compared CBT with waiting list controls; three compared CBT with appropriate placebo control groups. In all of these studies, patients in the CBT and control groups were also being treated with ADHD medications. Thus, they speak to the efficacy of CBT when given as an adjunctive treatment. The meta-analysis examined the waiting list controlled studies and the placebo controlled studies separately. For both types of study, the effect of CBT in reducing ADHD symptoms was statistically significant, with a standardized mean effect size of 0.4. This effect size, albeit modest, is large enough to conclude that CBT will be useful for some patients being treated with ADHD medications. Given these results, a reasonable guideline would be to refer adults with ADHD to a CBT therapist if they are being maintained on an ADHD medication but that medication is not leading to a complete remission of their symptoms and impairments. So listen to your patients. If, while on an appropriately titrated medication regime, they still complain about unresolved symptoms or impairments you need to take action. In some cases, changing their dose or shifting to another medication will be useful. If such approaches fail or are not feasible, you should consider referral to a CBT therapist.
 

REFERENCE
Young, Z., Moghaddam, N. & Tickle, A. (2016). The Efficacy of Cognitive Behavioral Therapy for Adults With ADHD: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Atten Disord.

http://medicalwritingtraining.com/Over the past few decades, a consensus has emerged among psychopathologists that some patients exhibit a well-defined syndrome referred to as sluggish cognitive tempo or SCT. There are no diagnostic criteria for SCT because it has not yet been accepted as a separate disorder by the American Psychiatric Association. People with SCT are slow-moving, indolent and mentally muddled. They often appear to be lost in thoughts, daydreaming, drowsy or listless. In reviewing these symptoms and the literature, Barkley suggested that SCT be referred to as Concentration Deficit Disorder (CDD). This term is less pejorative but is not yet commonly used. Becker and colleagues recently evaluated the internal and external validity of SCT via a meta-analysis of 73 studies. Internal validity addresses the consistency of SCT symptoms as measure of an underlying construct. Based on factor analytic studies using more than 19,000 participants, the authors concluded that the items purported to measure SCT are sufficiently correlated with one another to justify the idea that they measure the same underlying construct. Further support for internal validity was found in studies reporting high test-retest and interrater reliability. As regards ADHD, the authors found that SCT correlated significantly with both inattentive (r = 0.72) and hyperactive-impulsive (r = 0.46) symptoms in adults. The greater correlation with inattentive symptoms makes sense given the nature of SCT symptoms. So these data confirm two key points about SCT: 1) it is definitely associated with ADHD symptoms and 2) it is a meaningful construct in its own right. Very little is known about the implications of SCT for the treatment of ADHD. In a naturalistic study of 88 children and adolescents with ADHD, Ludwig and colleagues examined the effect of SCT on the response of ADHD symptoms to methylphenidate. They found no significant differences in treatment response between subjects with and without SCT. McBurnett and colleagues tested the effects of atomoxetine on SCT in children with ADHD and dyslexia (ADHD+D) or dyslexia only. Atomoxetine treatment led to significant reductions in both ADHD symptoms and SCT outcomes. Because controlling for changes in ADHD symptoms did not predict changes in SCT outcomes, the authors concluded that change in SCT in response to atomoxetine is mostly independent of change in ADHD. Although these data are preliminary and in need of replication, they do provide some guidance for clinicians dealing with ADHD patients who also have SCT.
 

REFERENCE
Becker, S. P., Leopold, D. R., Burns, G. L., Jarrett, M. A., Langberg, J. M., Marshall, S. A., McBurnett, K., Waschbusch, D. A. & Willcutt, E. G. (2016). The Internal, External, and Diagnostic Validity of Sluggish Cognitive Tempo: A Meta-Analysis and Critical Review. J Am Acad Child Adolesc Psychiatry 55, 163-78.

Ludwig, H. T., Matte, B., Katz, B. & Rohde, L. A. (2009). Do sluggish cognitive tempo symptoms predict response to methylphenidate in patients with attention-deficit/hyperactivity disorder-inattentive type? J Child Adolesc Psychopharmacol 19, 461-5.

McBurnett, K., Clemow, D., Williams, D., Villodas, M., Wietecha, L. & Barkley, R. (2016). Atomoxetine-Related Change in Sluggish Cognitive Tempo Is Partially Independent of Change in Attention-Deficit/Hyperactivity Disorder Inattentive Symptoms. J Child Adolesc Psychopharmacol.

Barkley, R. A. (2014). Sluggish cognitive tempo (concentration deficit disorder?): current status, future directions, and a plea to change the name. J Abnorm Child Psychol 42, 117-25.

Stephen_Faraone_PhD_AIA_2016_XM7MQd.png.jpgAdults with ADHD are more likely to have accidents, to drive unsafely, to have unsafe sex and to abuse substances. These ‘real world’ impairments suggest that people with ADHD may be predisposed to making risky decisions. Many studies have attempted to address this but is only recently that their results have been aggregated into a systematic review and meta-analysis. This paper by Dekkers and colleagues reports of 37 laboratory studies of risky decision making that studied a total of 1175 ADHD patients and 1222 controls. In these laboratory tasks, research participants are given a task to complete which require that they make choices which have varying degrees of risk and reward. Using the results of such experiments, researchers can score the degree to which participants make risky decisions. When Dekkers and colleagues analyzed the 37 studies together, they found substantial evidence that ADHD people are more likely to make risky decisions than people without ADHD. The tendency to make risky decisions was greatest for those who, in addition to having ADHD, also had conduct or oppositional disorders, which both have features that indicate antisocial behavior and aggressiveness. We cannot tell from these studies why ADHD patients make risky decisions. One explanation is that it is simply the impulsivity of ADHD people that leads to rash, unwise decisions. Another theory postulates that risky decisions reflect deficits in one’s sensitivity to rewards and punishments. If we are very motivated by reward and not aware of or affected by the possibility of punishment, then risky decisions will be common. The studies analyzed in the meta-analysis were not designed to demonstrate a link between risky decision making in the lab and the real world risky decisions that lead to accidents and other outcomes. It is reasonable to hypothesize such a link, which is why clinicians should consider risky decision making when planning treatments. If you suspect deficits in this area, it will not change your approach to pharmacologic treatment but, given the potential adverse consequences of risky decisions, you should consider referring such patients to cognitive behavior therapy for adult ADHD as this talk therapy may be able to teach ADHD adults how to cope with their decision making deficits.
 

REFERENCE
Dekkers, T. J., Popma, A., Agelink van Rentergem, J. A., Bexkens, A. & Huizenga, H. M. (2016). Risky decision making in Attention-Deficit/Hyperactivity Disorder: A meta-regression analysis. Clin Psychol Rev 45, 1-16.

http://medicalwritingtraining.com/One of the many great contributions of Dr. Russell Barkley was his conceptualization of ADHD as a disorder of self-regulation. ADHD people have difficulties regulating their behavior, which lead to the classic diagnostic criteria of hyperactivity and impulsivity and they have problem regulating cognitive processes which leads to the well-known inattentive diagnostic criteria for the disorder. In a 2010 paper, Dr. Barkley argued persuasively that deficient emotional self-regulation should also be considered a core component of ADHD alongside deficient behavioral and cognitive self-regulation. Although the DSM 5 did not add any emotional symptoms to the revised criteria for ADHD a new paper by Graziano and Garcia supports Dr. Barkley’s position. They conducted a meta-analysis of 77 studies of emotional dysregulation that comprised a total of 32,044 participants. They defined emotional dysregulation as the failure to modify emotional states in a manner that promotes adaptive behavior and leads to the success of goal directed activities. They identified three types of emotional dysregulation: emotion recognition and understanding (ERU), emotional reactivity/negativity/lability (ERNL) and empathy/callous-unemotional traits (ECUT). ERU refers to the ability to perceive, process and infer one’s own emotions and the emotions of others. ERNL refers to the intensity and valence of the emotional response. Reactivity refers to the rapidity of the emotional response (e.g., is a person quick tempered rather than reflective); negativity refers to the valence of the emotion. Is it extreme or appropriate to the situation; and lability refers to how quickly emotional states shift or cycle over time. The ECUT dimension has two poles. At one extreme is the empathic person whose reactions are guided by a clear understanding of the emotional states of others. At the other pole is the psychopath who shows little or no emotion to stimuli that evoke strong emotional reactions in the average person. When the data from the 77 studies was sorted into these three categories, the authors found that ADHD people had impairments in all three domains. The magnitude of impairment was a bit greater for ERNL than it was for ECUT and ERU, but not dramatically so. The association between ADHD and these domains of emotional dysregulation increased with increasing age. It is for this reason that some ADHD experts think that emotional dysregulation should be included in the diagnostic criteria for adult ADHD. Because behavioral hyperactivity diminishes with age, these criteria are less sensitive for adult ADHD than they are for child ADHD. Substituting emotional dysregulation items for hyperactivity items could, potentially, improve diagnoses of adult ADHD. Future work will address this issue. In the meanwhile, those who screen and diagnose adult ADHD should be aware that symptoms of emotional dysregulation might be the most prominent for some adults with the disorder.

 
REFERENCE
Barkley, R. A. (2010). Deficient Emotional Self-Regulation: A Core Component of Attention-Deficit/Hyperactivity Disorder. Journal of ADHD and Related Disorders 1, 5-37.

Graziano, P. A. & Garcia, A. (2016). Attention-deficit hyperactivity disorder and children’s emotion dysregulation: A meta-analysis. Clin Psychol Rev 46, 106-23.

Stephen_Faraone_PhD_ADHD_in_Adults
Does Acetaminophen use During Pregnancy Cause ADHD in Offspring?

Many media outlets have reported on a study suggesting that mothers who use acetaminophen during pregnancy may put their unborn child at risk for ADHD.   Given that acetaminophen is used in many over-the-counter pain killers, correctly reporting such information is crucial. 

As usual, rather than relying on one study, looking at the big picture using all available studies is best.  Because it is not possible to examine this issue with a randomized trial, we must rely on naturalistic studies.  

One registry study (http://www.ncbi.nlm.nih.gov/pubmed/24566677) reported that fetal exposure to acetaminophen predicted an increased risk of ADHD with a risk ratio of 1.37.  The risk was dose-dependent in the sense that it increased with increased maternal use of acetaminophen.  Of particular note, the authors made sure that their results were not accounted for by potential confounds (e.g., maternal fever, inflammation and infection). 

Similar results were reported by another group, which also showed that risk for ADHD was not predicted by maternal use of aspirin, antacids, or antibiotics.  But that study only found an increased risk at age 7 (risk ratio = 2.0) not at age 11. (http://www.ncbi.nlm.nih.gov/pubmed/25251831)

In a Spanish study, (http://www.ncbi.nlm.nih.gov/pubmed/27353198), children exposed prenatally to acetaminophen were more likely to show symptoms of hyperactivity and impulsivity later in life.  The risk ratio was small (1.1) but it increased with the frequency of prenatal acetaminophen use by their mothers. 

We can draw a few conclusions from these studies.  There does seem to be a weak, yet real, association between maternal use of acetaminophen while pregnant and subsequent ADHD or ADHD symptoms in the exposed child.  The association is weak in several ways: there are not many studies, they are all naturalistic and the risk ratios are small.  

So mothers that have used acetaminophen during pregnancy and have an ADHD child should not conclude that their acetaminophen use caused their child’s ADHD.  On the other hand, pregnant women who are considering the use of acetaminophen for fever or pain should discuss other options with their physician.  As with many medical decisions, one must balance competing risks to make an informed decision.