Diagnosing ADHD in preschool?
Contents
1 Early Diagnosis
A Swedish group, Wichstrøm et al. [6], wrote up a study looking at symptoms of attention-deficit/hyperactivity disorder (ADHD) in preschoolers. In their study, they cited several objections to assigning Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) diagnoses to preschoolers:
∙ Preschool children change so rapidly that symptoms will not cluster in any meaningful way
∙ Normal developmental variation will be wrongly interpreted as psychiatric symptomatology.
∙ Diagnosing young children will stigmatize them in ways that will negatively affect their development.
However, they continue that there are several reasons why research on the epidemiology of preschoolers should be pursued further [6]:
∙ Emerging empirical evidence from a variety of longitudinal studies supports the notion that there is continuity between preschool symptoms and disorders and later problems.
∙ If undetected child problems and relationships with caregivers and peers may deteriorate and with time become more resistant to change.
Early detection and intervention are therefore called for.
In the study, Wichstrøm et al. [6] reported 1.9 % of preschoolers in Scandinavia had ADHD symptoms, and that ADHD syptoms were often comorbid with other disorders in preschool children they observed.
2 The Preschool ADHD Treatment Study
A short-term efficacy and safety trial of methylphenidate (MPH) use in preschoolers diagnosed with moderate-to-severe ADHD was undertaken in the USA with long-term logitudinal followup [2]. Although effect sizes were smaller than those seen in school-age children, MPH did decrease ADHD symptoms in these preschoolers [1]. However, treatment with MPH hardly increases remission of ADHD symptoms over placebo, with only 21 % MPH treated children, and 13 percent of placebo treated children reaching criterion for remission [1]. While MPH is generally well tolerated, 30 % of parents reported moderate to severe adverse events during the trial [7]. These included emotional outbursts, difficulty falling asleep, repetitive behaviors/thoughts, appetite decrease, and irritability. This, along with reductions in growth rate (in both height and weight) reported by the study [4] highlight the importance of balancing the expected benefits in ADHD symptom reduction against a risk of reduced growth rates and possibly exagerated sensitivity to side effects in preschool-aged children.
2.1 Longitudinal followup
At followups 3 and 6 years later (mean age 7.4 years and 10.4 years respectively), most children were still on some sort of pharmacotherapy (65 % to 71 %), stimulant therapy being the most popular [5]. Though there was a slight reduction is symptoms over the 6 year followups, almost 80 % of the preschoolers enrolled in the study continued to be diagnosed with ADHD into mid-to-late childhood [3]. Interestingly, parent and teacher ratings of ADHD symptom severity were not significantly different between children on medication versus those off medication during followup [3].
Acronyms
- ADHD
- attention-deficit/hyperactivity disorder
- DSM-IV
- Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition
- MPH
- methylphenidate
References
[1] L. Greenhill, S. Kollins, H. Abikoff, J. McCracken, M. Riddle, J. Swanson, J. McGough, S. Wigal, T. Wigal, B. Vitiello, A. Skrobala, K. Posner, J. Ghuman, C. Cunningham, M. Davies, S. Chuang, and T. Cooper. Efficacy and safety of immediate-release methylphenidate treatment for preschoolers with ADHD. J Am Acad Child Adolesc Psychiatry, 45(11):1284–1293, Nov 2006.
[2] S. Kollins, L. Greenhill, J. Swanson, S. Wigal, H. Abikoff, J. McCracken, M. Riddle, J. McGough, B. Vitiello, T. Wigal, A. Skrobala, K. Posner, J. Ghuman, M. Davies, C. Cunningham, and A. Bauzo. Rationale, design, and methods of the Preschool ADHD Treatment Study (PATS). J Am Acad Child Adolesc Psychiatry, 45(11):1275–1283, Nov 2006.
[3] M. A. Riddle, K. Yershova, D. Lazzaretto, N. Paykina, G. Yenokyan, L. Greenhill, H. Abikoff, B. Vitiello, T. Wigal, J. T. McCracken, S. H. Kollins, D. W. Murray, S. Wigal, E. Kastelic, J. J. McGough, S. dosReis, A. Bauzo-Rosario, A. Stehli, and K. Posner. The Preschool Attention-Deficit/Hyperactivity Disorder Treatment Study (PATS) 6-year follow-up. J Am Acad Child Adolesc Psychiatry, 52(3):264–278, Mar 2013.
[4] J. Swanson, L. Greenhill, T. Wigal, S. Kollins, A. Stehli, M. Davies, S. Chuang, B. Vitiello, A. Skrobala, K. Posner, H. Abikoff, M. Oatis, J. McCracken, J. McGough, M. Riddle, J. Ghuman, C. Cunningham, and S. Wigal. Stimulant-related reductions of growth rates in the PATS. J Am Acad Child Adolesc Psychiatry, 45(11):1304–1313, Nov 2006.
[5] B. Vitiello, D. Lazzaretto, K. Yershova, H. Abikoff, N. Paykina, J. T. McCracken, J. J. McGough, S. H. Kollins, L. L. Greenhill, S. Wigal, T. Wigal, and M. A. Riddle. Pharmacotherapy of the Preschool ADHD Treatment Study (PATS) Children Growing Up. J Am Acad Child Adolesc Psychiatry, 54(7):550–556, Jul 2015.
[6] L. Wichstrøm, T. S. Berg-Nielsen, A. Angold, H. L. Egger, E. Solheim, and T. H. Sveen. Prevalence of psychiatric disorders in preschoolers. J Child Psychol Psychiatry, 53(6):695–705, Jun 2012.
[7] T. Wigal, L. Greenhill, S. Chuang, J. McGough, B. Vitiello, A. Skrobala, J. Swanson, S. Wigal, H. Abikoff, S. Kollins, J. McCracken, M. Riddle, K. Posner, J. Ghuman, M. Davies, B. Thorp, and A. Stehli. Safety and tolerability of methylphenidate in preschool children with ADHD. J Am Acad Child Adolesc Psychiatry, 45(11):1294–1303, Nov 2006.