Stimulants for ADHD
ADHD is a neurobehavioral disorder that is identified in approximately 8% of children and persists in 4% of adults.7 ADHD is characterized by impulsivity, motor restlessness, and inattention; the latter feature generally is more prominent with advancing age.8 If left untreated, ADHD has societal burdens, such as educational and occupational impairments.9 There is little data on ADHD in older adults and no placebo-controlled trials. For a case study of an older patient with ADHD treated with stimulants, see Box 2.10
Psychostimulants are considered the mainstay of ADHD treatment. First-line treatments include methylphenidate and amphetamines. A meta-analysis found a significant improvement in ADHD symptoms in adult patients taking psychostimulants compared with placebo, with no difference between immediate-release and long-acting formulations.11 Although these findings were reported in younger adults, they may be relevant for older persons as well. Wetzel and Burke12 described how ADHD presents in older adults and argued that the benefits of treating ADHD in this age group often outweigh the risks associated with psychostimulants, which can be diminished through careful screening.
Individuals who present with ADHD symptoms in late life often appear to be high functioning. Some may describe achieving academic and professional success, but may report chronic problems associated with inefficient learning and distraction compared with their peers because of untreated inattention symptoms. Faraone et al13 argue that similar to other illnesses, ADHD is represented by a spectrum of disease, which may be diagnosed in late life or as subthreshold ADHD. Individuals who did not meet diagnostic criteria in childhood or were not evaluated or treated may experience unremitting symptoms that contribute to functional impairment, persistent discouragement, and distress. Frustrations with distractibility, disorganization, and incompletion of tasks may have a psychological impact reflected by low self-esteem and irritability, and be a chronic source of occupational and relationship dysfunction. Diagnosing and treating ADHD in late life can improve longstanding functional impairments and overall quality of life.
Case 2: ‘Forgetfulness’ or undiagnosed ADHD?
Mr. J, age 66, is an attorney who presents for evaluation after he identified common features in friends who have attention-deficit/hyperactivity disorder (ADHD). In grade school, Mr. J’s teachers told him that he employed very little effort and was not meeting his potential, although he performed exceptionally well. He reports similar experiences throughout his education and says he was careful to select classes that were interesting, but did not require demanding projects or burdensome homework. In law school, he felt academically challenged for the first time but realized he had limited study skills. Mr. J graduated in the top 26th percentile of his class using “an unbelievable amount of effort compared with other students.”
Mr. J describes significant impairment in organizational skills and ability to keep track of time, procrastination, incompletion of tasks, and substantial distractibility during conferences. He says he has difficulty reading briefs depending on his emotional connection to the subject matter. Family history revealed that his mother likely had undiagnosed ADHD. He recently married and his wife encouraged him to seek treatment for “forgetfulness.” Mr. J maintains a busy, successful law practice but has become increasingly frustrated by his inability to follow through on simple tasks that could help grow the practice and generate revenue.
Mr. J has an elevated score on the Adult ADHD Symptom Rating Scale.10 He is referred to his primary care physician to evaluate his general health before beginning medication. At follow-up, Mr. J was started on lisdexamfetamine, 20 mg/d, titrated to 40 mg/d. On subsequent visits he reports improved symptoms without side effects. His vital signs are normal and he reports feeling more productive in his work and achieving significant improvement in the day-to-day operations of his practice.
Other uses
Depression. Although not a first-line treatment, psychostimulants have shown benefit for treating depressive disorders, particularly when patients require immediate improvement. These scenarios are common among medically ill patients, such as those with cancer, stroke, or human immunodeficiency virus (HIV), when it is urgent for patients to participate in their treatment plan. A double-blind, placebo-controlled, randomized study that looked at older depressed patients with medical comorbidities found that methylphenidate was well tolerated, worked quickly, and effectively treated depression.14 However, these results must be interpreted cautiously because the entire study was conducted in 8 days, which included a crossover design that administered methylphenidate 10 mg/d and 20 mg/d for 2 days each. A review of stimulant effectiveness in patients whose depression was associated with HIV, stroke, or cancer and in medically ill patients argued that although benefits have been reported, they must be interpreted tentatively because of a lack of randomized trials.15 However, limited evidence supports an effect of stimulants in treating fatigue, anorexia, pain, and sedation in these populations.15