ReadOnly Summary and analysis   (in plain language) 

JOURNAL ABSTRACT: 
Objective.  
     To assess the risk for substance use disorders (SUD) associated with previous exposure to psychotropic medication in a longitudinal study of boys with attention-deficit/hyperactivity disorder(ADHD). 
     The purpose of this study was to assess the risk for SUD associated with previous exposure to psychotropic medication in our longitudinal follow-up of psychiatrically and pediatrically referred boys with ADHD attending to co-morbidity with conduct disorder (CD), a well documented risk factor for SUD. We examined three competing hypotheses. The first is the null hypothesis that psychotropics would have no effect on the development of SUD in children with ADHD. The alternative hypothesis is that exposure to pharmacotherapy will be associated with higher risk for SUD in general and stimulant abuse in particular. Because SUD in children and adolescents with ADHD may arise from an attempt at self-medication, the third competing hypothesis posited that pharmacologic management would diminish the risk for SUD by controlling the core features of ADHD and promoting adaptive behavior and academic success.

Methods.  
     The cumulative incidence of SUD throughout adolescence was compared in 56 medicated subjects with ADHD, 19 nonmedicated subjects with ADHD, and 137 non-ADHD control subjects. Results. Unmedicated subjects with ADHD were at a significantly increased risk for any SUD at follow-up compared with non-ADHD control subjects (adjusted OR: 6.3 [1.8-21.6]). Subjects with ADHD medicated at baseline were at a significantly reduced risk for a SUD at follow-up relative to untreated subjects with ADHD (adjusted OR: 0.15 [0.04-0.6]). For each SUD subtype studied, the direction of the effect of exposure to pharmacotherapy was similar to that seen for the any SUD category. 

Conclusions. 
     Consistent with findings in untreated ADHD in adults, untreated ADHD was a significant risk factor for SUD in adolescence. In contrast, pharmacotherapy was associated with an 85% reduction in risk for SUD in ADHD youth. Key words: ADHD, pharmacotherapy, substance use disorders. As recently highlighted by Goldman et al,  the association between pharmacologic intervention in youth with attention-deficit/hyperactivity disorder (ADHD) and subsequent substance use disorder (SUD) remains a source of clinical and public health concern. Goldman et al questioned whether exposure to stimulant medication in youth with ADHD could lead to prescription drug abuse or serve as a gateway to the abuse of other drugs. The focus on the stimulants as a potential risk for SUD in ADHD youth is understandable, because stimulants are the drugs prescribed most commonly for this disorder. Given their well documented abuse potential, their use by many youth with ADHD has been of concern to both parents and clinicians. Whether pharmacotherapy leads to SUD in ADHD children has serious clinical implications. If such a link were documented, clinicians, patients, and families would need to weigh carefully the risk of SUD against the therapeutic benefit of medication. On the other hand, if pharmacotherapy does not lead to SUD, clinicians, patients, and families could approach pharmacologic treatment issues without ungrounded fears. Decreased apprehension toward appropriate pharmacotherapy in turn may lead to earlier intervention for affected youth with its attendant benefits of avoiding the academic, psychiatric, and interpersonal complications of ADHD. Unfortunately, as reviews of the literature show, no controlled studies of subjects with ADHD have evaluated adequately the putative link between SUD and pharmacotherapy, and there are only two published case reports of stimulant abuse by adolescents with ADHD receiving these compounds therapeutically.  Despite this dearth of data, the idea that pharmacotherapy increases the risk for SUD persists in diagnostic and treatment conferences and in the popular press.    

RESULTS AND CONCLUSIONS
    In a large, well characterized sample of pediatrically and psychiatrically referred ADHD and non-ADHD youth, pharmacotherapy for ADHD did not predict an increased risk for SUD. We found instead that subjects with ADHD who did not receive pharmacologic treatment were at a significantly increased risk for SUD suggesting that pharmacotherapy may protect children with ADHD from this risk. Although we cannot address potential differences between stimulant and nonstimulant drugs, it is reasonable to assume that the majority of our subjects indeed were exposed to stimulants, because stimulants are the mainstay of the treatment of this disorder.

    Our results also indicate that medication status is an essential modifier of the ADHD-SUD association. This finding extends our previous report that the risk for SUD was indistinguishable in ADHD and non-ADHD youth.24 However, in that analysis we did not account for medication status.24 As we report now, stratification by medication reveals that untreated ADHD is a significant risk factor for SUD even after correcting for comorbid CD.

    The increased risk for SUD in untreated youth with ADHD is consistent with our findings of significant ADHD-SUD associations in adults with ADHD.25,26 Because these adults had been primarily undiagnosed and untreated as children, they provide retrospective corroboration that ADHD, in the absence of pharmacotherapy, may increase the risk for SUD in subjects with ADHD.27 Although these findings require prospective confirmation, they suggest that adequate pharmacotherapy for ADHD in childhood may have a significant protective effect for the subsequent development of SUD in adulthood.

    Our findings should be viewed in consideration of additional methodologic limitations. The first pertains to the lack of an ideal control group for assessing the independent effect of pharmacotherapy on SUD onset. We did not present the comparison between medicated subjects with ADHD and non-ADHD control subjects, because the control subjects did not have ADHD, and therefore, did not have a comparable baseline risk for SUD. In such a comparison, the protective effect of pharmacotherapy would be commingled with the deleterious effects of ADHD, and the result would be biased with respect to both the effects of ADHD and its pharmacotherapy. Thus, comparisons must be limited to those groups differing in only one potential risk factor (ie, within ADHD subjects, medication vs no medication or within nonmedicated subjects, ADHD vs non-ADHD).

    There also were significant differences among medicated ADHD, unmedicated ADHD, and non-ADHD control groups in age, SES, risk of CD, and gender. We limited our analysis to males >15 years of age and corrected for other confounders with multiple logistic regression. Although logistic regression deals with the potential confounding attributable to the variables measured, it does not necessarily correct for the other unmeasured confounders that may be associated with those modeled. However, these unmeasured confounders are not likely to account completely for our findings, because they would need to be more prevalent and more strongly associated with SUD than are SES, CD, and parental history of SUD.

    Despite having a large sample of ADHD and non-ADHD children, we lacked adequate statistical power to evaluate fully the effect on different SUD subtypes, especially for stimulant/cocaine use disorder and tobacco A/D. The result of this reduction in power was that our estimates of relative risk were not very precise, and null findings cannot be considered conclusive. Nevertheless, despite the low power to test our hypotheses, it is reassuring to know that only a very small proportion (2%) of many exposed subjects (n = 56) suffered stimulant or cocaine use disorders.

    Finally, this study cannot make definitive conclusions regarding the risks associated with pharmacotherapy of ADHD beyond the age of our current sample, in females, or in nonwhite subjects. Only follow-up of this and of other samples of children treated for ADHD with stimulants and other medications will provide such answers. Despite these considerations, our results suggest that rather than inducing SUD in youth with ADHD, pharmacotherapy for ADHD may protect children with ADHD from this serious and deleterious outcome. 

  return to ADHD home page                    return to previous page    

ReadOnly Summary and analysis   (in plain language)
    A belief has persisted in popular and scientific literature that treatment of Attention Deficit Hyperactivity Disorder (ADHD) with drugs, such as Ritalin or the amphetamine-related drugs, might lead to abuse of stimulants or other addictive substances such as alcohol and marijuana.  The authors of this study, who have been conducting a long-term study of families where one or more members were diagnosed with ADHD, wanted to see if this were really the case.  They studied a small (212) sample of white males 15 years and older, some with ADHD who had been treated with drugs, some who had not been treated, and some who were not disgnosed with ADHD. They  looked for a connection between use of drug treatment and the abuse of drugs or alcohol.
    They found that adolescents with untreated ADHD were significantly more likely to have problems with alcohol, marijuana, hallucinogens, stimulants, and cocaine than were adolescents who received treatment, although not more likely to use tobacco. Both groups were more likely to development substance abuse problems, including tobacco,  than were subjects who were not diagnosed with ADHD.  They suggest that the success of drug treatment in reducing the behavioral and emotional difficulties associated with ADHD may thus reduce a principle cause of substance abuse. They reach the conclusion that drug therapy for ADHD does not put a child at risk for later abuse of either prescribed medications, recreational, or illegal drugs, but rather may play a role in reducing likelihood of such problems.  

Comments:
The authors do not mention anywhere in their report which drugs the treated ADHD subjects had received.  We are assuming it was Ritalin, but this may well not be the case.   This report, as all we have seen, leaves us wondering why there are so many more kids with behavioral abnormalities these days, especially "learning disorders", hyperactivity, attention deficit, and the like. Is there some sort of growing epidemic affecting children physiologically, perhaps from a environmental cause?  Are more kids in need of help being discovered, where before they suffered in untreated obscurity? Is it economics, the case of an industry (pharmaceuticals) finding and promoting new markets, and a new profession and field of study (special education) finding aand building a market for its talents and theories?  We would love to see research attempting to answer those questions!

  return to ADHD home page                    return to previous page