Attention-Deficit Hyperactivity Disorder: Critical Appraisal of Extended Treatment Studies

Abstract

, Char les Cun ning ham, PhD 7Key Words: attention-deficit hy per ac tiv ity dis or der, ADHD, sys tem atic re view, treat ment, stimu lants, be hav ioural ther apy A ttention-deficit hy per ac tiv ity dis or der (ADHD) (1) is a com mon psy chi at ric dis or der oc cur ring in ap proximately 5% of school-aged chil dren, ado les cents, and adults (1,2). It is a fre quent rea son for re fer ral to men tal health services (3). ADHD is first evi dent in the pre school years (4) and per sists in as many as 70% of in di vidu als through out childhood and ado les cence and into adult hood (5,6). Af fected in dividu als are at risk for op po si tional de fi ant dis or der (ODD), con duct dis or der (CD), de pres sion, anxi ety, and learn ing disabil ity (LD) (7). They are also at risk for the de vel op ment of de lin quency or crimi nal ity, and for school sus pen sion, academic un dera chieve ment, low self-esteem, and sub stance abuse (8). Treat ments must be of suf fi cient in ten sity to have an im me di ate im pact on the core ADHD symp toms, and they We un der took a sys tem atic re view of the lit era ture on the long-term treat ment of attentiondeficit hy per ac tiv ity dis or der (ADHD). We used sys tem atic strate gies to iden tify ran domized treat ment stud ies in which treat ment was ad min is tered for 12 weeks or more. We included 14 stud ies in volv ing 1379 sub jects. Be cause of the lim ited number of high-quality stud ies and the het ero ge ne ity of out come meas ures, we did not per form metaana ly sis. We rated 5 stud ies as ade quate for meth odo logi cal qual ity. Five stud ies fol lowed chil dren for more than 26 weeks. Phar ma cologic in ter ven tions were stud ied more fre quently than nonphar ma cologic ones. Six stud ies per mit ted evalua tion of the ef fects of com bined drug and be hav ioural in ter ven tion. Twenty-five dif fer ent out comes were meas ured us ing 26 dif fer ent tests. Stimu lant medi ca tion ap pears to re duce ADHD (7 stud ies), dys func tional so cial behav iour (6 stud ies), and in ter nal iz ing symp toms (2 stud ies). Avail able stud ies pro vide lit tle evi dence for im proved aca demic per form ance with stimu lants (3 stud ies). Medi ca tions other than stimu lants have not been stud ied ex ten sively (3 stud ies). Only 1 study showed that com bi na tion ther apy adds to the ef fects of medi ca tion. Rig or ous treat ment re search among rep re sen ta tive sam ples of ADHD in di vidu als is needed.(Can J Psy chia try 2002;47:337-348) Clini cal Im pli ca tions• Sys tem atic re views are im por tant tools for de ci sion mak ers but the meth odo logi cal rig our of ran dom ized con trolled tri als (RCTs) of long-term attention-deficit hy per ac tiv ity dis or d er (ADHD) treat ment is low.• These stud ies do not clar ify the ef fect of treat ment on im por tant out comes.• Com bined phar ma cologic and non phar ma cologic in ter ven tions yield the best out comes. Limi ta tions• The ef fects of non phar ma cologic treat ment and drugs other than stimu lants are lit ...

Dopamine Transporter Genotype and Stimulant Side Effect Factors in Youth Diagnosed with Attention-Deficit/Hyperactivity Disorder

“…Despite robust short-term efficacy in the majority of ADHD efficacy studies, many children and adolescents with ADHD discontinue treatment prematurely (Thiruchelvan et al 2001;Schachar et al 2002). This is presumably due to adverse effects contributing to poor tolerability (Efron et al 1998;Charach et al 2004).…”

Effects of Methylphenidate on Acute Math Performance in Children with Attention-Deficit Hyperactivity Disorder

“…Other studies demonstrate that long-term use of MPH does not show significant improvement in academic performance. 39,[40][41][42][43][44] Discrepancies in the results can, in part, be explained by the small sample sizes, the variance in the design and methodology of the studies, the differences in the ADHD diagnosis, and the assessment of improvement in academic performance. It is difficult to consider how much the academic performance of children with ADHD would decline or improve if they were not on psychostimulants.…”

What influences clinicians’ decisions about ADHD medication? Initial data from the Influences on Prescribing for ADHD Questionnaire (IPAQ)

“…Some models of ADHD highlight its status as a lifelong condition that requires long-term use of medication for its effective treatment. Alongside these, a number of concerns have been raised in the literature about the potential long-term chronic use of stimulants [29] not least in relation to brain development [30][31][32]. Unfortunately, there are little or no data from long term RCTs that would allow the evaluation of these claims and clinicians are left to manage this uncertainty without an evidence base to guide them.…”