Continuing Medical Education


Truths and Misconceptions

Annick Vincent  |  2014-10-10

Which of us has never been asked questions like “Doctor, are you really sure that attention deficit disorder with or without hyperactivity (ADHD) exists? Isn’t it just a social problem? How can you tell the difference between ADHD and other conditions that cause attention or behaviour problems? Why should I be concerned about this?” How would you label the following statements?


Dr. Annick Vincent, psychiatrist, practices at Clinique Focus, affiliated with the Centre médical l’Hêtrière, in Saint-Augustin-de-Desmaures. Dr. Simon-Pierre Proulx, general practitioner, practises in the family medicine group GMF de Loretteville in Quebec City. Dr. Sophie Lemelin, neuropsychologist, practises vat Clinique Focus and also at the Institut universitaire en santé mentale de Québec.

1. There is much more ADHD in North America than elsewhere in the world. False

Attention deficit disorder with or without hyperactivity (ADHD) affects from 5% to 8% of children1 and around 4% of adults2 not only in North America but also around the world. Most affected people have a clinical presentation combining inattention and impulsivity. Around 30% of them experience mainly symptoms of inattention. The term ADHD is used for all cases by qualifying the type of presentation shown over the last six months (combined type, predominantly inattentive type, predominantly hyperactive-impulsive type). In everyday language, when cognitive disorders are not combined with hyperactivity, the expression “attention deficit disorder” (ADD) is sometimes used alone without the word “hyperactivity.” For an excellent review on ADHD, refer to Dr. Barkley’s handbook.3

Access to assessment tools and treatment options vary across regions and remain a challenge. The prevalence of ADHD is relatively stable despite the rising number of diagnoses and prescribed treatments. This is explained in part by increased awareness, improved training, earlier screening, and the recognition of its persistence into adulthood and of its adverse effects, along with the benefits of specific treatments and accommodations.

2. ADHD runs in families. True

Although the exact causes of ADHD are not known, this disorder often has a strong hereditary component.3 Some of the known environmental risk factors are in utero exposure to nicotine, alcohol and heavy metals, malnutrition, gestational diabetes, twin pregnancies, premature birth and neonatal distress. In addition, secondary ADHD can develop following head trauma or chemotherapy treatments. Other neurological disorders, such as epilepsy, tics and neurofibromatosis, often co-occur with ADHD. It is therefore important to screen for them in the assessment.4

h Clinical Tip: You should screen for these risk factors in the assessment.


ADHD is a neurobiological disorder. The level of support given to people with ADHD can influence the course of their condition. A better understanding of ADHD helps in implementing strategies to reduce its effects (for sample strategies for children and adults, see the articles “ADHD: Tips and Tricks for Young People” and “ADHD: Tips and Tricks for Adults”).

3. Most adults with ADHD were diagnosed in their childhood. False

In 2006, a U.S. study examined the epidemiology of several psychiatric problems in adults. It found that ADHD affects 4.4% of the population. It very often co-occurs with other mental health problems (e.g., anxiety disorders, 47%; mood disorders, 38%) and causes significant functional impairments.2 Although nearly half of the study subjects were being treated for mental health problems (53.1% of women and 36.5% of men aged 18 to 44 years), only 10% of adults with ADHD were receiving specific treatment for this problem.

Parents consult their family physicians when their children display learning or behaviour problems. Individuals who are bright and have access to a favourable environment often consult later when their coping strategies start failing. Inattentive people may be diagnosed later in life because their symptoms are less “visible.” Adults seek medical advice on their own, sometimes upon a family member’s insistence. Once ADHD is recognized and treated in a family member, some adults seek treatment on their own. In our clinical experience, some adults try out the medication prescribed to a family member. It may therefore be useful and beneficial to find out if this applies to the patients who come to you for consultation.

Adults with ADHD are particularly affected by the chronic consequences triggered by cognitive disorders.5 They are distracted, their minds overwhelmed by racing thoughts. Despite their good intentions, they have difficulty performing tasks, they jump from one task to another, and they have a poor sense of time and time management. Administrative tasks and paperwork are major hurdles. Many have financial problems.

ADHD is often associated with impulsivity that hinders work productivity, driving ability and many other aspects of daily living. In addition, many find it hard to moderate the intensity of their emotional reactions. They often cope with their restlessness by channelling it into work or sports. Some use stimulants (caffeine, energy drinks, nicotine) or street drugs such as cannabis. More than half of those with ADHD develop a psychiatric problem that leads them to consult a doctor (see statement 5 below). According to a longitudinal study spanning a period of 33 years, ADHD can have major effects on several areas of life, and concomitant problems may emerge early, generally in adolescence or in early adulthood.6


Attention deficit disorder with or without hyperactivity (ADHD) affects from 5% to 8% of children and around 4% of adults. The hereditary factor implies that it can affect several members of the same family.

4. Everyone who has ADHD has a learning disability. False

Learning, language and coordination disorders also affect attention capacity and academic performance. When students are unable to understand information or have difficulty writing, they cannot keep up in class, they lose focus and may become agitated. Other factors must also be considered. For example, a low IQ reduces learning ability. Students with low IQs are then viewed as more immature and experience a variety of functional difficulties. Those with very high IQs (giftedness) can become bored and disruptive. They are more likely to drop out of school if not given the proper stimulation.

h Clinical Tip: A psychometric assessment helps detect learning disabilities and measure IQ. Language skills are assessed by a speech therapist, and motor aspects by an occupational therapist.


ADHD is not a learning disorder in itself, but it may hinder the learning process.7 Children with ADHD have difficulty concentrating in class and make careless mistakes due to inattention. To compensate for this, they take longer to read and to revise their work, which slows them down. They have difficulty not only following the teacher but also doing their reading assignments and extracting and summarizing information. They have messy handwriting. Their difficulty with starting and finishing tasks leads to late or incomplete homework assignments. Forgetfulness is a problem. Their schoolbags and desks are messy, which makes them lose their school supplies or school papers. Given that their marks are inconsistent, they are viewed as failing to meet expectations. Some students get discouraged and give up on their studies. On average, ADHD is associated with one year of academic delay compared with other students with the same potential.

h Clinical Tip: Academic performance should not be used as a screening indicator either for ADHD or for the effectiveness of drug treatment because some people with ADHD experience no apparent effects on their academic outcomes. Moreover, pharmacotherapy for ADHD improves concentration but does not in itself enable students to catch up on their academic delays. An individualized treatment plan is required when ADHD interferes with learning. Physicians can recommend coping strategies (see the articles “ADHD: Tips and Tricks for Young People” and “ADHD: Tips and Tricks for Adults”).

5. ADHD has a significant impact on daily life. True

People with ADHD have more problems not only in school but also in different areas of their lives.3-6,8 Young people who do not listen or who interrupt people may be seen as self-centred and may experience rejection. Many develop an anxiety disorder or a mood disorder. Some become oppositional, while others withdraw into themselves.

h Clinical Tip: ADHD may be mistaken for other problems. This makes it important to obtain a good medical history and to identify the time of symptom onset and the precipitating factors.
Oppositional behaviour, like the problems associated with ADHD, can hinder task performance and cause procrastination or task avoidance (see the article “ADHD: Tips and Tricks for Young People”). It is important to determine if the difficulties are generalized or if they occur in a specific setting that incites opposition to rules or authority.
People with ADHD are more likely to have low self-esteem and to experience sad moods, characteristics that must be distinguished from major depression. Impulsivity and depression may increase the risk of suicidal behaviour.
In addition, the chronic over-reactivity and hyperactivity associated with ADHD must not be mistaken for the manic episodes of bipolar disorder. An examination of the nature of the person’s difficulties and family history can be revealing. ADHD must be differentiated from an anxiety disorder that also causes cognitive impairments and agitation. ADHD often leads to performance anxiety. People with ADHD may compensate for this through hyper-organization or overplanning that appears compulsive. Some start avoiding anxiety-provoking situations, which increases their procrastination and social isolation. Clinicians should try to find out what is impairing their concentration and causing anxiety. A medical history will show whether the attention and concentration problems have been present since childhood, whether they emerged at a specific time or whether they are related to another problem.

ADHD may be complicated by a conduct disorder, often associated with a substance abuse problem or with personality disorders (especially those marked by impulsivity and emotional regulation problems, but also those of the avoidance or obsessive type). ADHD can explain underlying impulsivity but not illicit behaviours. However, it does increase the likelihood of substance abuse and tobacco use.

h Clinical Tip: Find out the order in which the symptoms appeared. Ask whether the patient is using toxic substances and try to determine their state of mind before they started using them and when they are not under the influence.


ADHD increases the risk of serious accidents, including head trauma and road accidents (as both pedestrians and drivers), and the risk of unplanned pregnancies. Young people have a harder time during the transition into adulthood when they are required to do things on their own. This is compounded by problems paying bills on time and managing their expenses. Getting ready in the morning and achieving a work-life balance are gruelling. Their sleep is affected by the difficulty with following a routine and agitation. Many of them still manage to get up early through obligation, which leads to a chronic lack of sleep, additional mental fatigue, and an increased risk of obesity. ADHD also hinders the ability to plan and prepare meals and may lead to irregular and impulsive eating habits.

At work, ADHD is associated with a lower income, uneven productivity and more frequent job changes. Parents with untreated ADHD have a harder time supporting their children and experience more tension with their partners. ADHD is also associated with a higher rate of interpersonal problems and marital separation.


ADHD is a neurobiological disorder that hinders self-regulation mechanisms. The brain of a person with ADHD works differently.


6. It has been scientifically proven that the brain of a person with ADHD works differently. True

Research has increased our understanding of how the ADHD brain works.9,10 There are no medical imaging tests to establish a clinical diagnosis. Neuroimaging studies have revealed a slight decrease in the volume and metabolism of some areas of the brain.9

The young ADHD brain also develops more slowly. Behavioural studies, as well as brain imaging studies (cortical thickness), have shown a 20% to 30% developmental delay in cortical maturation.11 Moreover, the adult ADHD brain has a more difficult time using the standard networks to perform tasks requiring attention (e.g., inactivation of the anterior cingulate cortex, reversible with an osmotic, controlled-release formulation of methylphenidate used to treat ADHD).9


The consequences of ADHD reach beyond school and affect several areas of functioning. Its clinical presentation may vary not only from person to person but also throughout life.

Scientists have hypothesized that the information transmitters that trigger dopamine and norepinephrine may be impaired. These transmitters govern the regulation of attention, movement and behaviour. Current medications that are effective in reducing ADHD symptoms all share the ability to improve the neurotransmission of these substances.

7. ADHD can be ruled out after an assessment with neuropsychological tests yielding results within the normal range. False

ADHD is a neurodevelopmental problem causing difficulties with regulating thoughts (inattention), movements (restlessness), behaviour (impulsivity) and even emotions (over-reactivity). Establishing a diagnosis is a clinical process that can be supplemented by a neuropsychological assessment. The presence of neuropsychological deficits helps support a diagnosis of ADHD in a more objective way. Impairments in attention capacity, working memory, information-processing speed, and executive functions are often observed in people with ADHD. However, the absence of these impairments does not rule out a diagnosis of ADHD. People with ADHD may in fact achieve results within the normal range on a battery of standard neuropsychological tests.12 These impairments can come to light by considering each person’s profile according to their own potential and the type of test used. A neuropsychological assessment helps to identify individual strengths and weaknesses and to support requests for school or work accommodations. In some cases, it is performed from the viewpoint of a differential diagnosis (IQ and learning disabilities). An IQ test can also have a therapeutic purpose. Objectively establishing an individual’s potential can provide a clearer understanding of their cognitive functioning and can improve their self-esteem.

Neuropsychological research has helped explain how ADHD affects the executive functions.13 People with ADHD have more difficulty with filtering stimuli, extracting and summarizing relevant information, and setting priorities. It is also harder for them to start and follow through with tasks and to efficiently switch between tasks (cognitive flexibility), especially if the task is long and less immediately enjoyable. Their performance is variable and depends on their level of interest. Their working memory (the ability to manipulate and access stored information in a timely manner and to use self-talk) is reduced. Their sense of time and their ability to project themselves into the future may also be impaired. However, a positive side of ADHD may be heightened creativity (the ability to find novel solutions).14-16 Detecting and effectively treating ADHD helps people make better use of this aspect and access their full potential.

8. A medical assessment is essential for diagnosing and managing ADHD. True

Everyone who daydreams or fidgets does not necessarily have ADHD! A number of medical and psychiatric problems that co-occur with ADHD complicate not only its clinical presentation but also its management (see statement 5 and the articles “In-Office Assessment of ADHD: Step-by-Step Approach” and “Pills and ADHD: Why, For Whom and How?”).4,8

Chaotic, stressful or unstimulating environments can lead to problems that mimic ADHD. People who try to do too much too quickly may also develop “pseudo ADHD.” Both Canada and Québec have adopted practice guidelines on assessing and treating ADHD4,17,18. Family physicians are key actors in the process for establishing a medical and psychiatric differential diagnosis and identifying relevant psychosocial elements.

ADHD is a common neurobiological disorder that can significantly affect people’s development. Early detection and treatment can greatly improve functioning and reduce the level of impairment resulting from this disorder. Further articles in this special “Focus on ADHD” edition of Le Médecin du Quebec propose strategies to better equip family physicians for ADHD assessment and management. //

French Version: Received: January 2013 Accepted: April 2, 2013
Translated in English: September, 2014

Dr. Annick Vincent has been a speaker and an advisory committee member for Biovail, Lundbeck, Bristol Myers Squibb, Lilly, Purdue, Janssen and Shire since 2010. She received grants from Purdue, Shire and Janssen from 2011 to 2013. Dr. Simon-Pierre Proulx is a speaker for Janssen and Shire and an advisory committee member for Janssen and Novo-Nordisk. Dr. Sophie Lemelin has no conflicts of interest to declare.


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