DEFINITION/DIAGNOSIS OF ATTENTION DEFICIT HYPERACTIVITY DISORDER
Attention deficit hyperactivity disorder (ADHD) is a behavior disorder defined by chronic and impairing behavior patterns that result in abnormal levels of inattention, hyperactivity, or their combination.1 It is characterized by the inability to maintain attention span and focus concentration at a normal developmental level. Attention deficit hyperactivity disorder is usually diagnosed in childhood, although the condition can continue into the adult years.2-4 Previously published reviews and practice parameters offer a comprehensive review of this information.5-8
Attention deficit hyperactivity disorder is diagnosed clinically without diagnostic laboratory or imaging tests. Those characteristics pertinent to athletes and their caregivers are provided in Table 1.9 In addition to the features mentioned above, behavioral features of ADHD can include low frustration tolerance, increased mood lability, dysphoria, poor self-esteem, and academic difficulties.
The diagnosis of ADHD is often made with input from standardized self-report scales or checklists completed by parents and/or teachers.10-13 Some scales contain items describing behavioral aspects of ADHD, with the respondent indicating the observed frequency of these behaviors, which can then be compared to developmental or age peers to determine if they reach the threshold for the ADHD classification. Behavioral checklists allow an assessment of behavior across contexts (ie, home, work, and school). While these self-report scales may be descriptive of ADHD, specificity of these scales is low as they may also reflect behaviors associated with comorbid conditions (eg, depression, anxiety). In addition, these scales may also reflect the perceptions and attitudes of the teachers and parents completing them.
In addition to self-report/behavioral observations, neuropsychological (NP) tests may provide further information for clinicians to reach a diagnosis. Measures of visual and/or auditory attention and concentration may reveal significant impairments. One disadvantage to formal NP tests is that these tests are typically performed in a low-distracting testing environment, which can often minimize the difficulties an individual usually has in the classroom or other more distractible environments.6 The results or pattern of performance from an NP evaluation can be very helpful in describing how attention and concentration difficulties may impact memory or problem-solving functioning for an individual. They may also reveal other processing or academic issues.
Attention deficit hyperactivity disorder is a common neuropsychiatric disorder, affecting 4-10% of all American children.14-18 In a study representative of the US adult population, Kessler studied 3199 subjects aged 18-44 years and found an overall prevalence of 4.4%.4 Although some of the symptoms of ADHD diminish or disappear with maturation, 65% to 85% of ADHD children continue to meet Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria as teenagers or even young adults. 3,19-21 Other studies have reported that ADHD persists into adulthood.22-26 The prevalence of ADHD in athletes has not been studied, although there is no reason to believe it would differ from the general population.
Special Considerations for Team Physicians
The DSM-IV diagnostic criteria for ADHD state that symptoms are present before age 7. While there is no adult onset/acquired ADHD, in some cases compensatory efforts in childhood and adolescence may push symptoms below threshold, with symptoms thus emerging after childhood when compensation efforts are reduced or unavailable. Therefore, Team Physicians may be called upon to care for athletes with ADHD at a variety of levels (ie, youth, college, and beyond). Athletes who remain undiagnosed may come under a Team Physician's care. It is also possible that they could have been misdiagnosed or improperly managed. Often, ADHD is diagnosed on the basis of positive medication response and not a comprehensive evaluation designed to rule out comorbidities or other diagnoses.
The Team Physician should be aware of resources (counselors, psychologists, neuropsychologists, and psychiatrists with experience in ADHD management) for evaluation of ADHD in their institution or community. In most instances, the Team Physician will want to include parents, certified athletic trainers, teachers, and coaches in the care plan of these athletes. Team Physicians should understand that the core symptoms associated with ADHD (Table 1) may often be perceived by others as laziness, lack of personal responsibility, or oppositional behavior.9 The Team Physician may be able to provide some perspective to coaches and others regarding such symptoms.
COMORBIDITIES AND VALUE OF TREATMENT
When ADHD is untreated, the prevalence of certain psychological disorders (eg, major depression, bipolar disorder, conduct disorder, oppositional-defiant disorder, antisocial personality disorder, substance use, and anxiety) is increased.3,27-33 Learning or language problems are frequent in patients with ADHD.28 Other possible consequences of untreated ADHD include dangerous driving,34 academic underachievement,35 impaired peer relationships, delinquent behavior, and impulsive sexual activity.34,36 When ADHD is treated, the development of substance use is decreased,27,37 as are the development of depression/anxiety disorder, disruptive behavior, and the likelihood of repeating a grade in school.38
TREATMENT OF ATTENTION DEFICIT HYPERACTIVITY DISORDER
The management of ADHD in athletes includes a combination of management modalities including behavioral, psychosocial, and medication treatment options. The ideal management is provided by a multi-disciplinary team, which can include a psychologist, psychiatrist, and team physician. Parents, certified athletic trainers, teachers, and coaches should also be an integral part of the multi-disciplinary team as they can work to monitor symptoms, behaviors, and the athlete's response to treatment.
While medications can help manage and ameliorate many signs and symptoms of ADHD, the inclusion of psychosocial treatment efforts to deal with the behavioral, emotional, and cognitive issues are thought to be a critical piece of the treatment plan.39 Behavior modification and behavior management techniques have been effective in dealing with the adjustment difficulties consequent to core ADHD symptoms.40,41 These difficulties can include poor academic performance, poor peer relationships, disruptive school behavior, and family interaction problems. Treatment approaches can include parent training,42 specific school environment interventions, and psycho-educational or psychotherapeutic interventions with the ADHD individual. Examples of psychotherapeutic interventions include training in time management skills, social skills, and problem-solving skills. For some individuals, the combination of psychosocial treatment modalities and medication is optimal;43 however, other individuals may be more responsive to medication alone. Some physicians consider behavioral management (nonmedication) first-line treatment, followed by medication options if necessary.
The Team Physician should be aware of the medications commonly used to treat ADHD and their side effects (Table 2). Approximately 56% of patients with ADHD receive pharmacologic treatment, and a majority of medications used are stimulants.44 Stimulant medications have been found to be helpful in over 75% of the patients receiving them.45-47
The side effects of stimulant medications are important to consider. Many stimulants utilized in treating ADHD increase core temperature, possibly increasing risk of heat injury. These agents may also mask signs and symptoms of fatigue and allow for a longer duration of exercise with elevated temperature >40°C.48,49 In situations of increased exogenous heat stress, team physicians should use special caution in prescribing stimulant medications. Contraindications to the use of stimulant medications include hypertension, glaucoma, hyperthyroidism, symptomatic cardiovascular disease, structural heart disease, psychosis, stimulant hypersensitivity, history of drug dependence, and concomitant use of a monoamine oxidase (MAO) inhibitor or St. John's Wort.7 If concern exists for a possible cardiovascular condition, evaluate with a careful history, physical examination, laboratory testing, electrocardiogram (EKG), echocardiogram, and consultation as necessary.
Special Considerations for Team Physicians
Team Physicians should be aware of medication treatment options and their effects on certain sport and athlete-specific situations. Important issues to review with the prescribing physician include compliance, response, and side effects of medications. An individualized approach, including the athlete's history and background, prior responses to interventions, support structures, and psychiatric and medical comorbid diagnoses is recommended. The sports medicine staff must be aware of the athlete's medications and how the athlete is taking them, as use may vary with athlete preference. Some athletes will only take medications episodically for school testing or for studying purposes. Some athletes will feel their sport performance is improved on stimulants, while others may temporarily stop taking them so that their sports play is more random and unfocused, which they feel improves their performance.50 When an athlete first starts taking medication, it is important to consider that the medication may affect exercise and performance; medication is best initiated in a low stress (eg, captain's practice) versus high stress (eg, game) activity.
The Attention Deficit Hyperactivity Disorder Athlete and Exercise
Athletes with ADHD face certain unique challenges. While the literature has traditionally focused on the cognitive and psychological aspects of ADHD, a few studies comment on motor performance. Children and adolescents with ADHD often demonstrate poor motor skills, coordination and balance.51,52 Despite this fact, anecdotal reports from children and teachers suggest activity/exercise may mitigate the impulsivity and inattentiveness that characterizes ADHD,53-56 and evidence demonstrates a statistically significant decrease in markers of anxiety and depression among ADHD subjects with higher levels of sports participation.57 Other results suggest the beneficial effect on ADHD may be dependent on the environment in which the athlete is exercising.58
The Attention Deficit Hyperactivity Disorder Athlete and Medications
Team physicians should understand the effects of medications commonly prescribed for ADHD on athletes during daily life and while engaged in athletic activities. While there is currently no cure for ADHD, medications are frequently used to successfully mitigate symptoms. The response to stimulant medications is generally rapid and predictable and results in decreases in disruptive symptoms, increases in attentiveness, and improvements in academic performance.59,60 The stimulants methylphenidate and dexamphetamine are equally effective, although methylphenidate has been associated with fewer side effects.61,62 Nonstimulant medications have also been approved for use in ADHD. Atomoxetine has been shown to be effective in treating ADHD63,64 with side effects similar to methylphenidate.65 Tricyclic antidepressants are sometimes used for treatment of ADHD; however, due to side effects, they are not the ideal choice for athletes. Bupropion is occasionally used as an adjunct to other medications in children, although use is off-label for ADHD. Children treated with bupropion alone enjoy less benefit and experience more side effects than those on methylphenidate.66,67
Stimulants often cause appetite suppression, which may represent an obstacle for the young athlete attempting to gain or maintain weight and strength for athletic performance. Delayed growth of up to 1 centimeter per year has also been reported with methylphenidate and dexamphetamine.68 The slowing in growth velocity for both weight and height seen with stimulants appears to be present with atomoxetine as well, but its effect on final height and weight is debatable.69 Height and weight should be monitored in those receiving medications, to watch for significant deviations in expected growth and development.69
Stimulant Use and Exercise: Special Considerations
Stimulant medications are shown to have ergogenic potential and are banned by the World Anti-Doping Agency (WADA) and the International Olympic Committee (IOC). Stimulants may enhance performance through improving attention to task, peer relationships, or balance.50,70 In college, students without ADHD, strength, power, and speed are not consistently increased with use of amphetamine, although measures of acceleration were enhanced.71 Potential performance enhancement includes a subjective sense of euphoria, improved concentration, and increased aggression, along with decreased pain reported by athletes.72 This perceived ergogenic effect may lead some athletes to seek out and/or abuse stimulants.73
In addition, the side effects of stimulants on metabolism, circulation, sweating, respiration, blood pressure, and endocrine gland function may place athletes at specific risk for complications. Stimulant medications have been used by athletes for weight control.44 Many stimulants utilized in treating ADHD increase core temperature and may promote heat injury. In addition, methyphenidate, modafinil, and bupropion appear to mask symptoms of fatigue when exercising in warm climates.48,49,74
In one study, trained cyclists received methylphenidate, and their time to exhaustion was increased in warm conditions. Core temperature and heart rate were increased in the subjects on methylphenidate, both at rest and with exercise, when compared to placebo in both temperate and warm conditions. In warm conditions, measurements often reached higher than 40°C. In this study, there was no change in the perception of effort or thermal stress, which could potentially place the athlete at higher risk for heat-related illness.48 Wellbutrin was found to show similar effects in warm conditions.74 Modafanil has shown elevation of core temperature at rest and during exercise in warm environments.75,48 These studies support the concern for an increased risk of heat injury in athletes using medications for treatment of their ADHD. Potential performance enhancement includes a subjective sense of euphoria, improved concentration, and increased aggression, along with decreased pain reported by athletes.72 This perceived ergogenic effect may lead some athletes to seek out and/or abuse stimulants.73
Cardiovascular Considerations for Stimulant Use and Risk for Sudden Cardiac Death: Special Considerations
Nearly all ADHD medications have cardiovascular effects. Therefore, Team Physicians must consider their side effects, possible association with sudden cardiac death (SCD), and the need for EKG monitoring. In a study by Safer, methylphenidate was found to elevate heart rate by 11 beats per minute in methylphenidate-naïve patients, compared to 4 beats per minute in patients with continued use.76 However, interested parties on both sides dispute the clinical significance of a 1-5 mmHg increase in blood pressure (still below hypertensive levels).3,77-79 Winterstein et al found increased emergency department visits for cardiovascular complaints (ie, syncope, dysrhythmia, tachycardia/palpitation, and elevated blood pressure) in patients taking methylphenidate and amphetamine salts. No clinically significant difference was found in the risk between methylphenidate and amphetamine salts.80,81
Sudden cardiac death is rare among athletes and is usually associated with congenital abnormalities.82 However, reports of cardiac arrhythmias related to sympathomimetics (ie, amphetamine, methamphetamine, 3,4-Methylenedioxymethamphetamine) raise concerns for athletes taking related medicines such as stimulants for ADHD. Team Physicians should refrain from prescribing stimulants to children with pre-existing heart disease or symptoms consistent with cardiovascular disease.83 Because estimated rates of sudden death in stimulant-treated ADHD patients do not exceed that of the general population, team physicians should not refrain from treating athletes with stimulants because of concerns about sudden death (Table 3).84
The American Heart Association (AHA) recommends monitoring blood pressure and heart rate and obtaining EKGs with nearly all medicine treatments of ADHD—stimulant and nonstimulant. They cite improved sensitivity for undiagnosed cardiovascular disease when EKG is added to history and physical, while acknowledging a lack of clinical trials to support the recommendation.85 While sharing AHA concerns about silent cardiovascular disease, the American Academy of Pediatrics (AAP) subsequently issued a policy statement that did not support the routine use of EKGs before initiating stimulant therapy and reinforced previously published clinical practice guidelines.7,86-88 The AAP contends that there is no proof of increased rates of SCD in patients taking medications for ADHD. It remains prudent for Team Physicians to periodically monitor blood pressure, heart rate, and exertional symptoms in athletes treated for ADHD.
The Attention Deficit Hyperactivity Disorder Athlete and Regulatory Issues
Stimulant Abuse and Misuse: Special Considerations
Stimulant abuse has emerged as a complex problem associated with the treatment of ADHD. Despite the risks associated with stimulant use, the use and abuse of these medications has increased. Team physicians must be attentive to signs of inappropriate use of ADHD medications among athletes. This awareness should not limit prescribing of such medications when a clear indication is present, since studies show children with ADHD who are treated with stimulants have higher function and lower subsequent rates of drug abuse.89
The potential risk of prescribed medications being sold or delivered to others as a “street drug” is always present. Data from college campus surveys reveal this practice is extensive and this “admitted” data may underestimate the true usage rate. Nearly 4% of college students nationwide admitted to using Ritalin at least once in 2006.90 In a 2008 survey of 2087 college students, 5.3% admitted to the nonmedical misuse of stimulants. Ritalin use occurred 4 times more frequently than Concerta.91 Sixteen percent of responders abused stimulant medications (96% preferred Ritalin) in a 2006 study at a northeastern US university.92 Finally, a survey study at a southeastern university found 34% of the participants reported the use of ADHD stimulants. Students misused drugs during academic stress and felt the agents reduced fatigue and increased reading comprehension, cognition, and memory.93
Collegiate, National, and International Elite Competition Regulations
Team Physicians taking care of college athletes should be familiar with the rules for athletes participating in sports governed by the National Collegiate Athletic Association (NCAA). Effective August 1, 2009, the NCAA implemented a policy which requires student-athletes who have ADHD and take stimulant medication, to provide “evidence that the student athlete has undergone clinical assessment to diagnose the disorder, is being monitored routinely for use of the stimulant medication and has a current prescription on file.”79
Student athletes that have ADHD diagnosed in childhood need to provide their institution a copy of the comprehensive assessment and history of treatment. If these are not available, then a comprehensive assessment must be performed to establish the diagnosis. The NCAA requires an annual clinical evaluation and reporting to the athletics department/sports medicine staff. The minimum requirements needed for documentation of ADHD diagnosis include (1) description of the evaluation process including assessment tools and procedures, (2) statement of the diagnosis, (3) history of ADHD treatment (previous/ongoing), (4) statement that a nonbanned ADHD alternative medication has been considered if a stimulant is currently prescribed, and (5) statement regarding follow-up and monitoring visits.
The NCAA does not require that physicians prescribe a trial of nonstimulant medications before prescribing stimulants, only that the prescribing physician considers nonstimulants first. The NCAA acknowledges that nonstimulant medication may not be as effective as stimulant medications in treating ADHD. It is important that Team Physicians taking care of NCAA athletes understand the NCAA regulations and provide education to athletes regarding the use and misuse of medications. A form that encompasses the NCAA requirements for documentation of ADHD (Appendix) as well as an introductory letter that Team Physicians can utilize to communicate and educate student athletes is provided for American Medical Society for Sports Medicine (AMSSM) members at www.amssm.org.
In contrast to the NCAA regulations, athletes who are also participating in events governed by the IOC and/or WADA are not allowed to use stimulant medications, even with a Therapeutic Use Exemption. These organizations require that the athlete with ADHD on stimulant medications stop taking these medications or risk disqualification. Given NCAA and international regulations of athletes using stimulant medications, the Team Physician should be aware of the nonstimulant and nonpharmacologic treatment options that exist for ADHD.
There has been an increase in the reported incidence of ADHD, which has raised concern for the use and misuse of stimulant medications. The Team Physician should be aware of the signs and symptoms of ADHD and the unique issues related specifically to the use of stimulant medications. These include the risk for cardiac complications in those with pre-existing cardiac disease and the potential risk for heat-related illness. Team Physicians should play a role in the evaluation and management of ADHD in athletes. In addition, the Team Physician should play a central role in educating athletes on the use, misuse, regulations, and restrictions regarding stimulant medications.
The following represent the position and recommendations of the AMSSM in respect of the diagnosis, treatment, and monitoring of athletes with ADHD. See Table 4 for a definition of scoring recommendations, which are based on those reported by Ebell et al.94
- Position: The diagnosis of ADHD should be made when the individual meets DSM-IV criteria, and more importantly, after the careful evaluation and consideration of potential competing comorbid diagnoses. Input from sources familiar with the individual's behavior and general responses across contexts is important. Thus, behavioral observation ratings, NP test data, and comprehensive clinical interview are all important components of a valid diagnosis (SOR A).
- Position: The optimal treatment/management approach for ADHD is an individualized one that includes behavioral therapies and consideration of medications. While there is strong evidence to support the use of several medications (atomoxetine, dextroamphetamine salts, and amphetamine salts) to effectively treat ADHD in different individuals (SOR A), psychological interventions (behavioral, cognitive, or counseling) can be very useful in managing the associated features and comorbid diagnoses in ADHD individuals (SOR C). Combined treatments (behavioral management and stimulant medication) represent the gold standard in ADHD treatment (SOR C).
- Position: Monitoring of athletes with ADHD should be individualized. Monitoring allows for the tracking of behavior, as well as comorbid behavioral issues, the latter of which might allow team members to modify management accordingly. The frequency of monitoring should be determined based on the initial clinical interview and individual needs (comorbidities and risk factors) of the student athlete; the initial clinical interview may also provide direction as to who would be best indicated to monitor (SOR C).
- Position: The decision to use medications during sport (versus only for academic/behavior reasons) is one that should be made on an individual basis. All athletes with ADHD likely benefit from general behavioral skill-oriented treatments, which include time management, organizational skills, stress management, and problem-solving skills training.40-42 Whether additional medication use is beneficial in the treatment of ADHD is a decision that should be individualized (SOR C).
- Position: The fear of potential abuse of stimulants or other recreational drugs is not justification for withholding pharmacologic treatment of ADHD. Taking stimulant medication does not increase an athlete's risk for abusing stimulants or other drugs. Treating a patient with ADHD actually reduces the risk of subsequent substance abuse (SOR A).
- Position: There is insufficient evidence to recommend routine EKG or additional cardiac testing in athletes without cardiac disease on medications for ADHD, except for the athlete on a tricyclic antidepressant. If an athlete on stimulants is at risk for cardiac disease, as defined by history, family history, or physical exam, or a screening EKG, and further workup/consultation is warranted. If an athlete is on stimulants and found to have a cardiac disease, alternative therapy should be strongly considered (SOR C).
- Position: There is no evidence to support withholding stimulant treatment for ADHD due to a fear of sudden cardiac death; however, athletes should be monitored for signs and symptoms suggestive of cardiac disease. The risk for sudden death in children, adolescents, and adults is higher in athletes than nonathletes, and the greatest risk occurs during peak exercise or immediately postexercise. The risk of sudden death in athletes without known cardiac disease is not increased with stimulant therapy for ADHD, but risks, benefits, and adverse reactions of treatment must be monitored (SOR C).
- Position: Exercise may improve ADHD symptomotology, and there is little potential harm in recommending continued physical activity in ADHD athletes. There is insufficient evidence for or against exercise as treatment of ADHD. However, subjective symptoms of ADHD and comorbid mood disorders may improve with exercise (SOR C).
- Position: There may be an increased risk of heat injury in athletes taking medications for ADHD when exercising in hot environments. Evidence suggests that an increased risk of heat injury may exist with certain ADHD medications such as methylphenidate, bupropion, and modafinil. Some evidence exists to suggest that athletes taking stimulant medications have elevated core temperatures while exercising, though an increased incidence of exertional heat injury or heatstroke in these groups has not been reported (SOR C).
- Position: Although the ergogenic effect of medications to treat ADHD is unclear, these medications are often used and misused for this reason. There are limited studies demonstrating an ergogenic effect of medications used to treat ADHD. However, despite the controversial evidence for an ergogenic effect, athletes may have a perception that an ergogenic effect exists, further increasing their use (SOR C).
- Position: Team Physicians should be aware of and educate the athlete on regulations and requirements with pharmacologic treatment of ADHD. Athletes with ADHD can participate at every level. However, both the IOC and WADA do not allow for the use of stimulant medication, even if a Therapeutic Use Exemption form is completed. At the NCAA level, athletes treated for ADHD with stimulant medication must complete an exemption form that includes a comprehensive evaluation using DSM-IV criteria, an Adult ADHD Rating Scale (behavior ratings or observations), an annual evaluation which includes measuring blood pressure and heart rate, and confirmation that nonstimulant medications have been considered (SOR A).
AMSSM Medical Exemption ADHD/ADD.
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