Adult outcome of child and adolescent attention deficit hyperactivity disorder in a primary care setting.

Objectives: To determine the adult status of children and adolescents previously diagnosed with attention deficit hyperactivity disorder (ADHD).

Methods: From a consecutive sample, a case series from a primary care, private physician, office-based practice was evaluated. Seventy-seven adults were eligible, having been diagnosed with ADHD as children and adolescents by Diagnostic and Statistical Manual of Mental Disorders, Revised Third and Fourth Editions criteria. Seventy-three adults were available for interviews. Parents and/or significant others were also interviewed. The same criteria used originally were employed in the adult follow-up analysis. Main outcome measures included rates of adult ADHD, other psychiatric disorders, and educational attainment.

Results: Of 73 participants, only 4 (5.5%) had retained ADHD into adulthood. Sixty-nine (94.5%) did not have adult ADHD. The majority of the cohort did not exhibit any disabling psychopathology, and most had achieved positive educational attainment.

Conclusions: Adult follow-up of children and adolescents diagnosed with ADHD shows adult ADHD is rare in primary care. The data suggests that clinicians can have the greatest impact on ADHD by concentrating on the evaluation and management of children and adolescents with the disorder.

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The Council on Scientific Affairs of the American Medical Association and a consensus statement from the National Institutes of Health state that adult attention deficit hyperactivity disorder (ADHD) "has become well established" (1) and that "for many individuals the impact of ADHD continues into adulthood." (2)

However, adult ADHD is a difficult and formidable diagnosis to make, and identified patients are a select group. (3,4) Accordingly, adult ADHD remains controversial and continues to generate differences of opinion. (5)

For example, a referred sample of adults presenting for evaluation of possible ADHD (6) and a longitudinal study following children with ADHD into adulthood (7) reported rates of adult ADHD of 32% and 66% respectively. In a review of 56 studies (32 retrospective, 11 family-genetic, and 13 prospective) ADHD persisted into adulthood in 39% of the participants. (8)

Conversely, 2 other prospective studies following children with ADHD into adulthood found lower rates of adult ADHD, 4 and 8% of the cohorts, respectively. (9,10) Using a nonlinear regression analysis of 9 prospective studies, Hill and Schoener (11) concluded that ADHD decreases by 50% every 5 years and at 20 years of age the rate of adult ADHD would only be 0.8%.

These contrasting viewpoints come from research generated in university-based clinics. How common is adult ADHD in primary care? What is the prognosis when a young patient is diagnosed with ADHD? How can clinicians have the greatest impact?

No primary care research has been done to answer these questions. The following study was therefore undertaken to address these issues by investigating the adult outcome of children and adolescents previously diagnosed with ADHD in a primary care setting.

Materials and Methods

Between 1990 and 1995, a consecutive sample of 123 children and adolescents were diagnosed with ADHD with information obtained from parents, teachers, and patients and application of Diagnostic and Statistical Manual of Mental Disorders. Revised Third Edition (DSM-III-R) (12) and, after August of 1994, Fourth Edition (DSM-IV) (13) criteria. All patients were from the author's rural, office-based practice. From this consecutive sample, 77 participants were over 18 years old in 2003 and qualified for the adult follow-up case series.

At the time of the original diagnosis, the 77 children and adolescents ranged in age from 6.3 to 15.7 years (mean [+ or -] SD age, 10.4 [+ or -] 2.2 yr). There were 60 males and 17 females. Sixty-three were white and 14 were African-American.

Using DSM-III-R criteria, 38 had ADHD and 18 had undifferentiated ADHD. Following recommended diagnostic protocols, normative ADHD rating scales were employed to corroborate a diagnosis of ADHD, undifferentiated. (14) Using DSM-IV criteria, 9 had ADHD, combined, and 12 had ADHD, predominantly inattentive.

Eighty-one comorbidities were exhibited by the 77 children and adolescents, including oppositional defiant disorder (n = 24), psychosomatic complaints (n = 20), learning disabilities (n = 13), social problems (n = 12), communication disorders (n = 4), dysphoria (n = 3), enuresis (n = 3), and separation anxiety (n = 2).

Oppositional defiant disorder, enuresis, and separation anxiety were diagnosed by DSM criteria. (12,13) Learning disabilities and communication disorders were diagnosed by school psychologists and speech language pathologists, respectively. Social problems were diagnosed using the asocial domain of the Conner's Teacher Rating Scale (15) and noting t scores of 1.5 SD or greater above the mean. Psychosomatic complaints and dysphoria were descriptive problems and not considered disorders.

Forty-three lived with both biologic parents, 15 with a parent and step-parent, and 19 were from single-parent households.

Eight parents had a history of major depression and 2 had generalized anxiety disorder.

All 77 children and adolescents received psychostimulant therapy with individual titrations according to behavioral and academic responses and side effects. Comorbidities were identified and treated. Patients, families and teachers received ongoing education about ADHD, coexisting disorders, and each intervention.

At adult follow-up, in addition to patient interviews, parents and/or significant others were also interviewed. Data regarding ADHD, other psychiatric disorders, educational attainment and updated demographic information were obtained from these multiple sources. The same DSM criteria employed for the original diagnosis were used in the adult follow-up analysis.

The diagnostic protocols used for the children, adolescents and adults were consistent with contemporary practice guideline recommendations. (16,17)

Results

Seventy-three adults from the original cohort of 77 children and adolescents were evaluated. Only 4 were unavailable for adult follow-up.

There were 57 males and 16 female participants ranging in age from 18.2 to 25.8 years (mean [+ or -] SD age, 20.9 [+ or -] 2.1 yr). Sixty were white and 13 were African-American.

Forty-nine had graduated from high school and 7 were still in high school and expected to graduate (77% completion rate). Six had completed at least one year of postsecondary education and 20 were still attending college or vocational/technical school. Two had college degrees. Seventeen students (23%) had dropped out of high school before graduation. Of these 17 pupils, 9 had been evaluated for special education and 6 had attended resource classes.

Length of psychostimulant therapy for the cohort ranged from 4 to 133 months (mean [+ or -] SD 47.4 [+ or -] 32.3 mo).

Among the participants, only 4 patients met diagnostic criteria for adult ADHD. (n = 4, 5.5% adult ADHD). Two comorbidities, learning disability (n = 1) and anxiety disorder (n = 1), were exhibited. Each person retained the same subtypes (DSM-III-R ADHD [n = 1], undifferentiated ADHD [n = 1], DSM-IV ADHD, predominantly inattentive [n = 2]), that had been previously diagnosed in childhood and adolescence. All 4 continued to take psychostimulants. As expected, the length of medication treatment was longer in these adults.

Sixty-nine participants did not meet diagnostic criteria for adult ADHD (n = 69, 94.5% nonadult ADHD, see Table 1).

Current psychiatric diagnoses in the nonadult ADHD patients included major depression (n = 3), conduct disorder (n = 3), substance abuse (n = 2) and panic disorder (n = 2). These results are comparable to 1 year prevalence rates in the general population reported in The Primary Care Version of the DSM-IV (18) (see Table 2).

Because of the size differences between the adult ADHD and nonadult ADHD groups, statistical comparisons were not calculated.

Discussion

Follow-up studies of children and adolescents diagnosed with ADHD with input from parents and teachers give the most reliable measure of adult outcome. (19) The present study, which followed this design, revealed that only 5.5% of the participants had adult ADHD at follow-up. The majority of the cohort, 94.5%, did not retain ADHD into adulthood.

These findings are consistent with the results from the 2 prospective studies cited in the Introduction, which yielded results of 4 and 8% retention of ADHD into adulthood. (9,10) A concern that the rates would have been higher if the parent's opinion had been used, instead of just the adult patient interviews, (7) was not a consideration in the present study, which integrated the input of multiple informants.

The present study data supports the conclusion of Hill and Schoener (11) that ADHD decreases over time, and that by adulthood the rate of ADHD is low.

The 4 participants with adult ADHD met full DSM criteria for the disorder. It has been suggested that adults who exhibit symptoms of ADHD, but do not meet full diagnostic criteria, should still be included. (20,21) According to DSM-IV, these patients would qualify for inclusion as ADHD "in partial remission." (13) However, as noted by Faraone et al (22) "this category has not been validated with empirical studies."

A limitation to the present study is that only one investigator conducted all phases of the research. In a private, office-based practice this is the only practical protocol. A primary care physician's knowledge about his patients and ability to accurately diagnose psychiatric conditions are assumed.

No control group of children and adolescents without ADHD were identified and followed concurrently. But the objectives of the study were addressed without these comparisons.

Previous adult-outcome studies of children with ADHD from university-based clinics show only 30% of the cohorts have no disabling conditions as adults. (23) However, in the present study, the majority of the participants, 81%, who had been diagnosed with ADHD and multiple comorbidities as children and adolescents, did not exhibit any impairing psychopathology at adult follow-up. The inclination of children and adolescents with any psychiatric disorder to have worse outcomes as adults (24) was not seen. Over 75% completed high school, with 50% of these graduates attending college or vocational/technical schools. Eight were married and four had children. Two others were single parents. None of the cohort was a parent in a blended family.

This favorable outcome data, from a community-based practice with patients and families in their natural environment, is important to primary care practitioners. When ADHD is diagnosed, clinicians can advise families that with comprehensive treatment, the long-term outlook for their children and adolescents to become normal functioning adults is good.

The results of the present study show that adult ADHD is rare in primary care. Furthermore, the data suggests that clinicians can have the greatest impact on ADHD by devoting the majority of their time to delineating effective strategies to use in the management of ADHD in children and adolescents. Clearly, additional studies from primary care settings are needed to continue addressing these issues.

The artist is nothing without the gift, but the gift is nothing without
work.
--Emile Zola

Table 1. Comparison of participants

                              Adult ADHD            Non-Adult ADHD
                               (n = 4)                 (n = 69)

Gender
  Male                         3                    54
  Female                       1                    15
Mean age (years)              19.6 [+ or -] 1.3     21 [+ or -] 2.1
Race
  White                        3                    57
  African-American             1                    12
Education
  Attending High School        1                     6
  Learning Disabled            1                     1
  High School Graduate         3                    46
  Dropped Out of High School   0                    17
  Post-High School Ed          3                    22
  College Degree               0                     2
Family Structure
  Married                      0                     8
  Single                       4                    61
Length of stimulant           99.5 [+ or -] 35      44.4 [+ or -] 29.7
  treatment (mo)

Table 2. Comparison of psychiatric disorders

                          Non-ADHD                 Primary Care
                     Adults (a) (n = 69)         Version DSM4 (b)

Major depression           4.1                        5
Panic disorder             2.7                        1.3
Substance abuse            2.7                        0.2-2.0
Conduct disorder           4.1                        1.5-5.5

(a) Current diagnoses, percentage.
(b) One-year prevalence rates, percentage.

Accepted March 11, 2004.

References

1. Goldman LS, Genel M, Bezman RJ, et al. Diagnosis and treatment of attention-deficit/hyperactivity disorder in children and adolescents. JAMA 1998;279:1100-1107.

2. National Institute of Health consensus development conference statement: Diagnosis and treatment of attention-deficit/hyperactivity disorder (ADHD). J Am Acad Child Adolesc Psychiatry 2000;39:182-193.

3. Murphey K. Adults with attention deficit hyperactivity disorder: assessment and treatment considerations. Seminars Speech Lang 1996;17:245-253.

4. Stern HP, Garg A, Stern TP. When children with attention-deficit/hyperactivity disorder become adults. South Med J 2002;95:985-991.

5. Spencer T, Biederman J, Wilens TE, et al. Adults with attention-deficit/hyperactivity disorder: a controversial diagnosis. J Clin Psychiatry 1998;59(suppl 7):59S-68S.

6. Roy-Byrne P, Scheele L, Brinkley J, et al. Adult attention-deficit hyperactivity disorder: assessment guidelines based on clinical presentation to a specialty clinic. Compreh Psychiatry 1997;38:133-140.

7. 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.

8. Spencer T, Biederman J, Wilens T, et al. Is attention-deficit hyperactivity disorder in adults a valid disorder? Harvard Rev Psychiatry 1994;1:326-335.

9. Mannuzza S, Klein RG, Bessler A, et al. Adult psychiatric status of hyperactive boys grown up. Am J Psychiatry 1998;155:493-498.

10. Mannuzza S, Klein RG, Bessler A, et al. Adult outcome of hyperactive boys. Arch Gen Psychiatry 1993;50:565-576.

11. Hill JC, Schoener EP. Age-dependent decline of attention deficit hyperactivity disorder. Am J Psychiatry 1996;153:1143-1146.

12. American Psychiatric Association. Diagnostic and statistical manual of mental disorders, revised third edition. Washington DC, American Psychiatric Association, 1987.

13. American Psychiatric Association. Diagnostic and statistical manual of mental disorders, fourth edition. Washington DC, American Psychiatric Association, 1994.

14. Barkley RA. Differential diagnosis, in Barkley RA, (ed): Attention deficit hyperactivity disorder a handbook for diagnosis and treatment. New York, Guilford Press, 1990: pp 184.

15. Conners CK. Conners' rating scales. North Tonawanda, New York, Multi-Health Systems, Inc., 1990.

16. Goldstein S, Goldstein M. Making the diagnosis of ADHD, in Goldstein S, Goldstein M (eds): Managing attention disorders in children a guide for practitioners. New York, John Wiley and Sons, 1990, pp 150-211.

17. Searight HR, Burke JM, Rottnek F. Adult ADHD: evaluation and treatment in family medicine. Am Fam Physician 2000;62:2077-2086.

18. American Psychiatric Association. Diagnostic and statistical manual of mental disorders, fourth edition, primary care version. Washington DC, American Psychiatric Association, 1995.

19. Hechtman L. Long-term outcome in attention-deficit hyperactivity disorder. Child Adolesc Psychiatry Clin North Am 1992;1:553-565.

20. Spencer TJ, Biederman J, Wilens TE, et al. Overview and neurobiology of attention-deficit/hyperactivity disorder. J Clin Psychiatry 2002; 63(suppl 12):S3-S9.

21. Biederman J, Mick E, Faraone SV. Age-dependent decline of symptoms of attention deficit hyperactivity disorder: impact of remission definition and symptom type. Am J Psychiatry 2000;157:816-818.

22. Faraone SV, Biederman J, Spencer T, et al. Attention-deficit/hyperactivity disorder in adults: an overview. Biol Psychiatry 2000;48:9-20.

23. Hechtman L. Predictors of long-term outcome in children with attention-deficit/hyperactivity disorder. Pediatric Clin North Am 1999;46:1039-1052.

24. Baumgaertel A. Copeland L, Wolraich ML. Attention deficit hyperactivity disorder. In: Wolraich ML, editor. Disorders of development and learning: practical guide to assessment and management. St. Louis, Mosby, 1996, pp 424-447.

RELATED ARTICLE: Key Points

* Only 5.5% of the sample retained attention deficit hyperactivity disorder (ADHD) into adulthood.

* Over 80% of the adults had no disabling psychopathology.

* With comprehensive treatment of childhood and adolescent ADHD, the long-term outlook is positive.

Louis H. McCormick, MD

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