Adult attention-deficit/hyperactivity disorder (ADHD) has always been a difficult-to-diagnose disorder for clinicians. This is mostly due to the lack of authentic diagnostic tools for adults, as well as because the Diagnostic and Statistical Manual of Mental Disorders, fifth edition,1 criteria for an ADHD diagnosis require evidence of symptoms present before age 12 years, which is not always known. Although ADHD symptoms were described more than 100 years ago in children, it is only in recent times that the adult form has received appropriate clinical attention; there are now medications approved by the US Food and Drug Administration to treat adult ADHD.
Whereas a definitive prevalence of ADHD is difficult to determine, some data from meta-analysis suggest worldwide prevalence between 5.29%2 and 7.1% in children and adolescents,3 and 3.4% (range, 1.2%–7.3%) in adults.4 There is compelling data showing that approximately 50% to 66% of childhood ADHD persists into adulthood.5–8 Some children and adolescents develop effective strategies for managing inattention and concentration difficulties, so academic and occupational problems are not evident early on. Functional impairment may not become apparent until adulthood when new responsibilities challenge those strategies. Psychiatric diseases like depression, anxiety, personality disorders, substance use disorders, and bipolar disorder co-occur with ADHD9–13 in many patients, and need to be treated accordingly. Substance use disorder is the most common psychiatric comorbidity with ADHD, seen in 39.2% of adult patients with ADHD.11 Particular concerns, such as drug diversion, arise with comorbid ADHD and substance use disorders. There are no consensus guidelines available for this comorbidity;14 however, findings from pharmacotherapy suggest only mild improvement in ADHD without changes in substance use unless the addiction was first stabilized.15 Current research suggests that ADHD medications used concurrently with recreational drugs neither worsen nor improve the underlying substance use disorder.16
In summary, diagnosis of adult ADHD requires a careful history, particularly evidence of social and academic difficulties during childhood. Reviewing prior psychiatric medical records and collateral information from family members can provide key information toward a clearer diagnosis. Although structured diagnostic interviews and rating scales are helpful, formal neuropsychological testing can also be considered when a diagnosis remains unclear. Nonprescribed stimulant use is a significant problem in college-aged people, with current estimates ranging from 5% to 35% in that population.17 Research has shown that stimulant misuse and diversion are more widespread problems than abuse or addiction.18 Once the diagnosis of ADHD is ascertained in adults, general treatment principles apply, but must be weighed against an increased risk of diversion of stimulant medications in adults. Choosing between the two approved classes (stimulants vs nonstimulants) is mainly a function of tolerability, safety, and physician comfort with prescribing. As substance use disorder is highly prevalent in the population of adults with ADHD, nonstimulant medications are helpful treatment options. Nonstimulants represent an attractive, yet often underused treatment option.
This issue of Psychiatric Annals discusses how to properly diagnose ADHD in adults, as it is truly an ethical dilemma and a diagnostic challenge for many clinicians. We discuss these challenges with illustrative cases as well as detailed descriptions of medication treatment options for those patients who may be at risk for substance abuse. The articles also address the fact that some adult patients with ADHD outgrow the condition, whereas others require ongoing treatment.
- American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Arlington, VA: American Psychiatric Publishing; 2013.
- Polanczyk G, de Lima MS, Horta BL, et al. The worldwide prevalence of ADHD: a systematic review and meta regression analysis. Am J Psychiatry. 2007;164:942–948 doi:10.1176/ajp.2007.164.6.942 [CrossRef].
- Willcutt EG. The prevalence of DSM-IV attention-deficit/hyperactivity disorder: a meta-analytic review. Neurotherapeutics. 2012;9:490–499. doi:10.1007/s13311-012-0135-8 [CrossRef].
- Fayyad J, de Graaf R, Kessler R, et al. Cross-national prevalence and correlates of adult attention-deficit hyperactivity disorder. Br J Psychiatry. 2007;190:402–409 doi:10.1192/bjp.bp.106.034389 [CrossRef].
- Barkley RA, Fischer M, Smallish L, et al. The persistence of attention-deficit/hyperactivity disorder into young adulthood as a function of reporting source and definition of disorder. J Abnorm Psychol. 2002;111:279–289 doi:10.1037/0021-843X.111.2.279 [CrossRef].
- Ebejer JL, Medland SE, van der Werf J, et al. Attention deficit hyperactivity disorder in Australian adults: prevalence, persistence, conduct problems and disadvantage. PLoS One. 2012;7:e47404. doi:10.1371/journal.pone.0047404 [CrossRef].
- Faraone SV, Biederman J, Mick E. The age-dependent decline of attention deficit hyperactivity disorder: a meta-analysis of follow-up studies. Psychol Med. 2006;36:159–165 doi:10.1017/S003329170500471X [CrossRef].
- Lara C, Fayyad J, de Graaf R, et al. Childhood predictors of adult attention-deficit/hyperactivity disorder: results from the World Health Organization World Mental Health Survey Initiative. Biol Psychiatry. 2009;65:46–54. doi:10.1016/j.biopsych.2008.10.005 [CrossRef].
- Novik TS, Hervas A, Ralston SJ, et al. Influence of gender on attention-deficit/hyperactivity disorder in Europe--ADORE. Eur Child Adolesc Psychiatry. 2006;15(suppl 1):15–24 doi:10.1007/s00787-006-1003-z [CrossRef].
- Kessler RC, Adler L, Barkley R, et al. The prevalence and correlates of adult ADHD in the United States: results from the National Comorbidity Survey Replication. Am J Psychiatry. 2006;163:716–723 doi:10.1176/ajp.2006.163.4.716 [CrossRef].
- Pineiro-Dieguez B, Balanza-Martinez V, García-García PCAT Study Group. Psychiatric comorbidity at the time of diagnosis in adults with ADHD: the CAT Study. J Atten Disord. 2016;20(12):1066–1075 doi:10.1177/1087054713518240 [CrossRef].
- Steinhausen HC, Nøvik TS, Baldursson G, et al. ADORE Study Group. Co-existing psychiatric problems in ADHD in the ADORE cohort. Eur Child Adolesc Psychiatry. 2006;15(suppl 1):I25–I29 doi:10.1007/s00787-006-1004-y [CrossRef].
- Friedrichs B, Igl W, Larsson H, et al. Coexisting psychiatric problems and stressful life events in adults with symptoms of ADHD--a large Swedish population-based study of twins. J Atten Disord. 2012;6:13–22. doi:10.1177/1087054710376909 [CrossRef].
- Upadhyaya HP. Managing attention-deficit/hyperactivity disorder in the presence of substance use disorder. J Clin Psych. 2007;68(suppl 11):23–30
- Zulauf CA, Spirch SE, Safren SA, Wilens TE. The complicated relationship between attention deficit/hyperactivity disorder and substance use disorders. Curr Psychiatry Rep. 2014;16(3):436. doi:10.1007/s11920-013-0436-6 [CrossRef].
- Mariani JJ, Levin FR. Treatment strategies for co-occurring ADHD and substance use disorders. Am J Addict. 2007;16(suppl 1):45–54 doi:10.1080/10550490601082783 [CrossRef]
- Wilens TE, Adler LA, Adams J, et al. Misuse and diversion of stimulants prescribed for ADHD: a systematic review of the literature. J Am Acad Child Adolesc Psychiatry. 2008;47(1):21–31. doi:10.1097/chi.0b013e31815a56f1 [CrossRef].
- Harstad E, Levy SCommittee on Substance Abuse. Attention-deficit/hyperactivity disorder and substance abuse. Pediatrics. 2014;134(1):e293–e301. doi:10.1542/peds.2014-0992 [CrossRef].