Search the Library
NOTE: This is a new search platform (as of May 2026). If you do a search and don’t get the results you were expecting, please email us at ctnlib@uw.edu to let us know? (If possible, please share your exact search strategy. Thank you!)
Enter keywords and hit Enter (or click the magnifying glass) to search. You can then also select document type or subject/topic to narrow results further (or just use those for searching without a keyword). Results display below this search form.
Document types
Subjects
- CTN-#### format for protocols (CTN-0001, e.g.)
- “exact phrase” (if phrase is not found, it will return results that contain all terms
- word1 NOT word2
- word1 word2 (finds both words)
- Click title to access full-text
- “Show details” reveals abstract & other info
- Checkboxes select items for copy/pasting or printing
- Need help getting a copy of a journal article?
Email ctnlib@uw.edu
Search results
High levels of missing outcome data for biologically confirmed substance use (BCSU) threaten the validity of substance use disorder (SUD) clinical trials. Underlying attributes of clinical trials could explain BCSU missingness and identify targets for improved trial design.
We reviewed 21 clinical trials funded by the NIDA National Drug Abuse Treatment Clinical Trials Network (CTN) and published from 2005 to 2018 that examined pharmacologic and psychosocial interventions for SUD. We used configurational analysis-a Boolean algebra approach that identifies an attribute or combination of attributes predictive of an outcome-to identify trial design features and participant characteristics associated with high levels of BCSU missingness. Associations were identified by configuration complexity, consistency, coverage, and robustness. We limited results using a consistency threshold of 0.75 and summarized model fit using the product of consistency and coverage.
For trial design features, the final solution consisted of two pathways: psychosocial treatment as a trial intervention OR larger trial arm size (complexity=2, consistency=0.79, coverage=0.93, robustness score=0.71). For participant characteristics, the final solution consisted of two pathways: interventions targeting individuals with poly- or nonspecific substance use OR younger age (complexity=2, consistency=0.75, coverage=0.86, robustness score=1.00).
Conclusions: Psychosocial treatments, larger trial arm size, interventions targeting individuals with poly- or nonspecific substance use, and younger age among trial participants were predictive of missing BCSU data in SUD clinical trials. Interventions to mitigate missing data that focus on these attributes may reduce threats to validity and improve utility of SUD clinical trials.
Related protocols: CTN-0002, CTN-0003, CTN-0004, CTN-0006, CTN-0007, CTN-0009. CTN-0013, CTN-0014, CTN-0015, CTN-0017, CTN-0021, CTN-0029, CTN-0030, CTN-0031, CTN-0037, CTN-0044, CTN-0046, CTN-0048, CTN-0051, CTN-0053
In a multisite, randomized study (CTN-0029), a 3-month course of osmotic-release oral system mehtylphenidate (OROS-MPH) improved smoking cessation in a group of patients with higher baseline severity in Attention Deficit/Hyperactivity Disorder (ADHD). This treatment, however, worsened smoking cessation outcome in the group with lower baseline ADHD severity. This studied aimed to examine whether this differential treatment effect persisted after OROS-MPH was discontinued.
A secondary analysis of the 1-month follow-up data from CTN-0029 after discontinuation of OROS-MPH was conducted (N=134). Nicotine patch was tapered during this month. Researchers tested whether OROS-MPH had an effect on self-reported 7-day abstinence by week, as well as possible treatment by baseline ADHD severity interactions.
Abstinence diminished overall in time after the end of the treatment. In the high baseline severity group, patients who received OROS-MPH had an advantage in 7-day abstinence at week 15 (40% for OROS-MPH vs. 32% for placebo). In the lower severity group (n=121), no difference was detected (29% for OROS-MPH vs. 32% for placebo) between the two treatment groups. There was also a significant treatment by baseline ADHD severity interaction.
Conclusions: OROS-MPH promotes abstinence beyond the course of treatment for patients with more severe ADHD, while the paradoxical effects in the lower baseline severity group is not persistent after medication discontinuation. Targeting ADHD in smoking cessation as a comorbidity therefore can have broader impact with more precise patient selection.
Related protocols: CTN-0029
A double blind, placebo-controlled randomized trial evaluation osmotic-release oral system methylphenidate (OROS-MPH) for smoking cessation revealed a significant interaction effect in which participants with higher baseline ADHD severity had better abstinence outcomes with OROS-MPH while participants with lower baseline ADHD severity had worse outcomes (CTN-0029). This study examined secondary outcomes that might bear on the mechanism for this differential effect treatment effect. Longitudinal analyses were conducted to evaluate the effect of OROS-MPH on three secondary outcomes (ADHD symptom severity, nicotine craving, and withdrawal) in the total sample (N=255, 56% male) and in the high (N=134) and low (N=121) baseline ADHD severity groups.
Results found that OROS-MPH significantly improved ADHD symptoms and nicotine withdrawal symptoms in the total sample, and exploratory analyses showed that in both higher and lower baseline severity groups, OROS-MPH statistically significantly improved these two outcomes. No effect on craving overall was detected, though exploratory analyses showed statistically significantly decreased craving in the high ADHD severity participants on OROS-MPH. No treatment by ADHD baseline severity interaction was detected for the outcomes.
Conclusions: Methylphenidate improved secondary outcomes during smoking cessation independent of baseline ADHD severity, with no evident treatment-baseline severity interaction. Results suggest divergent responses to smoking cessation treatment in the higher and lower severity groups cannot be explained by concordant divergence in craving, withdrawal, and ADHD symptoms severity, and alternative hypotheses may need to be identified.
Related protocols: CTN-0029
In randomized controlled trials (RCTs), a common strategy to increase power to detect a treatment effect is adjustment for baseline covariates. However, adjustment with partly missing covariates, where complete cases are only used, is inefficient. This paper considers different alternatives in trials with discrete-time survival data, where subjects are measured in discrete-time intervals while they may experience an event at any point in time. The results of a Monte Carlo simulation study, as well as a case study of randomized trials in smokers with attention deficit hyperactivity disorder (CTN-0029), indicated that single and multiple imputation methods outperform the other methods and increase precision in estimating the treatment effect. Missing indicator method, which uses a dummy variable in the statistical model to indicate whether the value for that variable is missing and sets the same value to all missing values, is comparable to imputation methods. Nevertheless, the power level to detect the treatment effect based on missing indicator method is marginally lower than the imputation methods, particularly when the missingness depends on the outcome.
In conclusion, complete case analysis is wasteful and drops the power level to a large degree, resulting in an undetectable treatment effect. Also, it can introduce bias in the estimate of the treatment effects when the missingness mechanism depends on the outcome variable. This method is therefore invalid and the authors do not recommend it. Instead, it appears that imputation of partly missing (baseline) covariates should be preferred in the analysis of discrete-time survival data.
Related protocols: CTN-0029
A preponderance of relevant research has indicated reduction in anxiety and depressive symptoms following smoking abstinence. This secondary analysis of data from the National Drug Abuse Treatment Clinical Trials Network study CTN-0029 investigated whether the phenomenon extends to smokers with attention deficit hyperactivity disorder (ADHD). The study setting was an 11-week double-blind placebo-controlled randomized trial of osmotic release oral system methylphenidate (OROS-MPH) as a cessation aid when added to nicotine patch and counseling. Participants were 255 adult smokers with ADHD. The study outcomes were: anxiety (measured by the Beck Anxiety Inventory (BAD)) and depressed mood (Beck Depression Inventory II (BDI)), measured 1 week and 6 weeks after a target quit day (TQD). The main predictor was point-prevalence abstinence measured at weeks 1 and 6 after TQD. Covariates were treatment (OROS-MPH vs. placebo), past major depression, past anxiety disorder, number of cigarettes smoked daily, demographics (age, gender, education, marital status) and baseline scores on the BAI, BDI, and DSM-IV ADHD Rating Scale.
Results found that abstinence was significantly associated with lower anxiety ratings throughout the post-quit period (p<0.001). Depressed mood was lower for abstainers than non-abstainers at week 1 (p<0.05), but no longer at week 6 (p=0.83). Treatment with OROS-MPH relative to placebo showed significant reductions at week 6 after TQD for both anxiety (p<0.05) and depressed mood (p<0.001), but not at week 1. Differential abstinence effects of gender were observed. Anxiety and depression ratings at baseline predicted increased ratings of corresponding measures during the post-quit period.
Conclusions: Stopping smoking yielded reductions in anxiety and depressed mood in smokers with ADHD treated with nicotine patch and counseling. Treatment with OROS-MPH produced better outcomes on the post-cessation mood ratings compared to placebo, albeit in a delayed manner, suggesting that OROS-MPH could be an important adjunct for achieving smoking abstinence in this population. Validation of findings from this secondary analysis could advance discovery and development of treatments for persons dually diagnosed with nicotine dependence and ADHD.
Related protocols: CTN-0029
Traditional approaches to subgroup analyses that test each moderating factor as a separate hypothesis can lead to erroneous conclusions due to the problems of multiple comparisons, model misspecification, and multicollinearity. This study aimed to demonstrated a novel, systematic approach to subgroup analyses that avoids these pitfalls. A Best Approximating Model (BAM) approach that identifies multiple moderators and estimates their simultaneous impact on treatment effect sizes was applied to a randomized, controlled, 11-week, double-blind efficacy trial on smoking cessation of adult smokers with attention-deficit/hyperactivity disorder (ADHD), randomized to either OROS-methylphenidate (n=127) or placebo (n=128) and treated with nicotine patch (National Drug Abuse Treatment Clinical Trials Network protocol CTN-0029). Binary outcomes measures were prolonged smoking abstinence and point prevalence smoking abstinence.
Although the original clinical trial data analysis showed no treatment effect on smoking cessation, the BAM analysis showed significant subgroup effects for the primary outcome of prolonged smoking abstinence: (1) lifetime history of substance use disorders, and (2) more severe ADHD symptoms. A significant subgroup effect was also shown for the secondary outcome of point prevalence smoking abstinence — age 18-29 years.
Conclusions: The BAM analysis resulted in different conclusions about subgroup effects compared to a hypothesis-driven approach. These divergent findings underscore the need for investigators to consider more advanced statistical methods to better analyze subgroup effect sizes. By examining moderator independence and avoiding multiple testing, BAMs have the potential to better identify and explain how treatment effects vary across subgroups in heterogeneous patient populations, thus providing better guidance to more effectively match individual patients with specific treatments.
Related protocols: CTN-0029
Osmotic-release oral system methylphenidate (OROS-MPH) did not show overall benefit as an adjunct smoking cessation treatment for adult smokers with ADHD in a randomized, placebo-controlled, multicenter study in the National Drug Abuse Treatment Clinical Trials Network (CTN-0029). A secondary analysis revealed a significant interaction between ADHD symptom severity and treatment-response to OROS-MPH, but did not account for other baseline covariates or estimate the magnitude of improvement in outcome if treatment were optimized. This present study addressed the gaps in how this relationship should inform clinical practice. Using data from the CTN trial (N=255, six sites in five US states), researchers built predictive models to calculate the probability of achieving prolonged abstinence, verified by self-report, and expired carbon monoxide measurement. The potential improvement in achieving prolonged abstinence was evaluated, both with and without stratification on baseline ADHD severity. Predictive modeling demonstrated that the interaction between baseline ADHD severity and treatment group was not affected by adjusting for other baseline covariates. A clinical trial simulation showed that giving OROS-MPH to patients with baseline Adult ADHD Symptom Rating Scale (ADHD-RS) >35 and placebo to those with ADHD-RS <= 35 would significantly improve the prolonged abstinence rate.
Conclusions: In smokers with ADHD, utilization of a simple decision rule that stratifies patients based on baseline ADHD severity can enhance overall achievement of prolonged smoking abstinence. This type of personalized treatment based on baseline ADHD symptom severity alone could significantly improve clinical outcome over randomized assignment. Similar analysis methods should be considered for future clinical trials for other substance use disorders.
Related protocols: CTN-0029
This secondary analysis of data from National Drug Abuse Treatment Clinical Trials Network protocol CTN-0029 (NIDA-CTN-0029 A Pilot Study of Osmotic-Release Methylphenidate in Initiating and Maintaining Abstinence in Smokers with ADHD) aimed to determine whether treatment of attention deficit/hyperactivity disorder (ADHD) with osmotic-release oral system (OROS) methylphenidate promotes abstinence from smoking among smokers with ADHD who have greater severity of ADHD symptoms at baseline or greater improvement in ADHD during treatment. CTN-0029 was a randomized, double-blind, 11-week trial conducted between December 2005 and January 2008 at 6 clinical sites. Adult cigarette smokers (aged 18-55 years) who met DSM-IV criteria for ADHD were randomly assigned to OROS methylphenidate (72 mg/d) (n=127) or matching placebo (n=128). All participants received nicotine patches (21 mg/d) and weekly individual smoking cessation counseling. Logistic regression was used to model prolonged abstinence from smoking (ascertained by self-report and breath carbon monoxide testing) as a function of treatment, baseline ADHD Rating Scale-IV (ADHD-RS) score, change in ADHD-RS score during treatment, and their interactions.
Results found that treatment interacted with both ADHD-RS score at baseline and change in ADHD-RS score during treatment. Among patients with higher ADHD-RS scores (>36) at baseline and the most improvement in ADHD during treatment (change score > 24), 70% of those who took OROS methylphenidate achieved abstinence from smoking compared to 36.8% of those who took placebo. In contrast, among patients with the lowest ADHD-RS baseline scores (< 30), 30.3% of those who took OROS methylphenidate achieved abstinence from smoking compared to 60.7% of those who took placebo.
Conclusions: OROS methylphenidate, in combination with nicotine patch, may be an effective treatment for nicotine dependence among smokers with more severe ADHD and more robust response of ADHD symptoms to medication. OROS methylphenidate may be counterproductive among smokers with lower severity of ADHD. The identification and aggressive treatment of ADHD and other comorbidities hold out the promise of a treatment strategy complementary to existing medication and behavioral approaches.
Related protocols: CTN-0029
This article reports on a study examining predictors of methylphenidate-induced increases in blood pressure (BP). In this secondary analysis of CTN-0029, a randomized, double-blind, placebo-controlled smoking cessation trial, non-hypertensive adult smokers with attention deficit hyperactivity disorder randomized to osmotic-release oral system methylphenidate (OROS-MPH) (n=115) were matched one-to-one on baseline systolic BP (SBP) (+/-5 mm Hg) with participants randomized to placebo (n=115) and followed for 10 weeks. In adjusted mixed linear models of SBP and diastolic BP (DBP), baseline normal SBP (P<.0001) and DBP (P<.0001) were associated with significant OROS-MPH–induced increases compared with placebo, whereas significant increases were not observed in participants with baseline prehypertensive SBP (P=.27) and DBP (P=.79). Participants randomized to OROS-MPH with baseline normal BP had increased odds of developing either systolic (odds ratio [OR], 3.32; 95% confidence interval [CI], 1.41–8.37; P=.006) or diastolic prehypertension (OR, 4.32; 95% CI, 1.56–14.0; P=.004) compared with placebo using simple logistic regression.
Conclusions: This study suggests two findings: (1) adult ADHD participants with baseline normal blood pressure are more susceptible to the BP-raising effects of OROS-MPH than those with baseline prehypertensive BP, and (2) normotensive adults with ADHD have significantly greater odds of developing prehypertension when treated with OROS-MPH compared with placebo. Since previous studies have shown adverse cardiovascular outcomes associated with prehypertension, further studies are needed to clarify the long-term consequences, especially given the growing consensus of ADHD as a treatable lifelong illness.
Related protocols: CTN-0029
Few studies have evaluated predictors of smoking cessation outcomes in smokers with attention-deficit/hyperactivity disorder (ADHD), which could help to improve suboptimal treatment outcomes in this population. The purpose of this study was to examine pretreatment thoughts about smoking abstinence (i.e., desire to quit, perceived difficulty quitting, and expected success in quitting) as predictors of smoking cessation outcomes in smokers with ADHD and to determine the extent to which treatment adherence mediates these relationships.
Participants in this CTN ancillary investigation were adult smokers with ADHD (n=255) who were enrolled in National Drug Abuse Treatment Clinical Trials Network protocol CTN-0029 (“A Pilot Study of Osmotic-Release Methylphenidate in Initiating and Maintaining Abstinence in Smokers with ADHD”) and received either osmotic-release oral system methylphenidate (OROS-MPH) or placebo in combination with transdermal nicotine replacement and brief cessation counseling. Bootstrapped logistic regression models were generated to test main effects of thoughts about abstinence on smoking cessation outcomes and to examine treatment adherence as a mediator of these relationships. Desire to quit and expected success in quitting, but not perceived difficulty of quitting, predicted smoking cessation outcomes, as did all of the treatment adherence variables (i.e., percent sessions attended, counselor ratings of counseling adherence, and percent patch adherence). Counseling adherence partially mediated the relationship between smoking cessation outcomes and both pretreatment desire to quit and expected success.
Conclusions: Smokers with ADHD who have higher self-efficacy (i.e., expected success) and motivation (i.e., desire) to quit are more adherent to smoking cessation counseling and have better smoking cessation outcomes. Additional research is needed to determine whether treatment-seeking smokers with ADHD would benefit from an intervention designed to increase self-efficacy and motivation to quit. Interventions such as contingency management, for example, have been shown to increase motivation and self-efficacy for quitting in non-treatment-seeking adult smokers and might effectively promote long-term abstinence in smokers with ADHD as well.
Related protocols: CTN-0029
Adults with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for both cigarette smoking and being overweight or obese. Although smoking cessation tends to result in weight increase, potentially initiating or exacerbating weight problems, adults with ADHD who are treated with osmotic release system methylphenidate (OROS-MPH) tend to lose weight. It is unclear how the use of OROS-MPH during a smoking-cessation attempt might affect the typical weight gain that accompanies cessation. This study focused on changes in weight and hunger during a smoking cessation attempt in 215 adults with ADHD who completed National Drug Abuse Treatment Clinical Trials Network trial CTN-0029 (“A Pilot Study of Osmotic-Release Methylphenidate in Initiating and Maintaining Abstinence in Smokers with ADHD”). Patients in this study were randomized to either OROS-MPH (n=107) or placebo (n=108), with both groups also receiving open-label transdermal nicotine replacement and counseling. Participants who received OROS-MPH lost an average of 1.6% of their body weight during the 11-week study, whereas those who received placebo gained an average of 1.3% of their weight (p<.001). Hunger ratings were lower in the OROS-MPH group than in the placebo group.
Conclusions: The use of OROS-MPH during a smoking-cessation attempt prevents weight gain in adults with ADHD who substantially reduce or quit smoking. Although its effects on hunger and weight did not translate into better overall efficacy for smoking cessation in this study (see Winhusen et al., 2010), when coupled with OROS-MPH’s previously established safety in smokers with ADHD and its efficacy in reducing ADHD symptoms, this clear indication of its effects on postcessation weight gain suggests that future research on the potential benefit of OROS-MPH among particular subgroups of smokers with ADHD — such as those who are deterred from making a quit attempt due to weight concerns or who are prone to relapse as a result of weight gain — may be in order.
Related protocols: CTN-0029
Pharmacotherapy trials for treating tobacco dependence would benefit from behavioral interventions providing treatment consistent with clinical practice guidelines but not directing participants to treatment not evaluated in the trial. The Smoke Free and Living It behavioral intervention manual includes participant and interventionist guides and is designed to provide both practical counseling and intra-treatment support. In protocol CTN-0029, researchers utilized this intervention manual as part of their multicenter, randomized clinical trial of smokers with attention deficit hyperactivity disorder. In the study, they evaluated how the interventional manual performed in a “train-the-trainer” model requiring uniform counseling across 6 sites and 15 interventionists. The skill-adherence of the interventionists and the intervention-adherence of the participants was analyzed. The 2555 randomized participants completed 9.3 +/- 2.8 sessions (mean +/- SD), with 157 participants (61.6%) completing all 11 of the sessions and 221 (86.7%) completing at least 6 of the 11 sessions. Of the 163 sessions for which the study interventionists were evaluated, 156 (95.7%) were rated as adherent to protocol and “meeting expectations” on at least 6 of 7 established criteria, illustrating that fidelity can be maintained with minimal supervision.
Conclusions: The self-help and interventionists guides of the Smoke Free and Living It manual can thus be used to provide behavioral intervention with a high rate of adherence by both the interventionists and the participants. This manual can be used as a self-help guide, an interventionist guide, or both, and can be tailored to a specific research protocol, regardless of the size of the study or number of study sites. The Smoke Free and Living It manual meets the requirements of the United States Public Health Service Clinical Practice Guideline, can be adapted to specific research protocols, and provides a useful option for behavioral intervention during clinical trials for smoking cessation.
Related protocols: CTN-0029
Multisite trials, the gold standard for conducting studies in community-based settings, can mask variability across sites resulting in misrepresentation of effects in specific sites. In a placebo-controlled trial of osmotic-release oral system methylphenidate (OROS-MPH) as augmentation treatment for smokers with attention deficit hyperactivity/impulsivity disorder (ADHD) (protocol CTN-0029), three types of sites were selected according to their clinical research specialty (ADHD, smoking cessation, and general mental health). Analysis was conducted to determine if clinical outcomes, that is, reduction in ADHD symptoms and smoking cessation rates, and the effect of treatment on these outcomes would differ by type of site. A total of 255 adult smokers diagnosed with ADHD were enrolled in three clinic types: 72 in ADHD, 79 in tobacco dependence, and 104 in the mental health clinics. The three site-types were similar in demographic characteristics, smoking history, baseline level of ADHD symptoms, and history of psychiatric illness. Site-type but not site-type-by-treatment-interaction predicted prolonged smoking abstinence. A significant three-way interaction of site-type, treatment, and time predicted improvement in ADHD symptoms. Moderate to strong effects of OROS-MPH relative to placebo were observed in the mental health and the ADHD clinics, while only a weak effect was observed in the tobacco dependence clinics. Accordingly, had the study only been conducted in tobacco dependence clinics, an erroneous null or, at best, weak effect of OROS-MPH on ADHD symptoms might have emerged.
Conclusions: OROS-MPH benefit varied by site for reducing ADHD symptoms but not for improving smoking abstinence. The uneven presence of site-type effects, observed in this analysis, affirms the need for a priori consideration and measurement of potentially influential site-related factors in the design and analysis of multisite trials. Scientific assessment of site-type effects can indicate the generalizability of findings from multisite trials and should be routinely incorporated in the design of multisite trials.
Related protocols: CTN-0029
Psychostimulants are effective treatments for attention-deficit/hyperactivity disorder (ADHD) but may be associated with euphoric effects, misuse/diversion, and adverse effects. These risks are perceived by some clinicians to be greater in substance-abusing adolescents relative to non–substance-abusing adults. The present study evaluates the subjective effects, misuse/diversion, and adverse effects associated with the use of osmotic-release oral system methylphenidate (OROS-MPH), relative to placebo, for treating ADHD in adolescents with a substance use disorder (SUD) as a function of substance use severity and compared these risks with those associated with the treatment of ADHD in adults without a non-nicotine SUD. Datasets from two randomized placebo-controlled trials of OROS-MPH for treating ADHD, one conducted with 303 adolescents (CTN-0028) with at least one non-nicotine SUD and one with 255 adult smokers (CTN-0029), were analyzed. Outcome measures included the Massachusetts General Hospital Liking Scale, self-reported medication compliance, pill counts, and adverse events (AEs). Euphoric effects and misuse/diversion of OROS-MPH were not significantly affected by substance use severity. The euphoric effects of OROS-MPH did not significantly differ between the adolescent and adult samples. Adults rated OROS-MPH as more effective in treating ADHD, whereas adolescents reported feeling more depressed when taking OROS-MPH. The adolescents lost more pills relative to the adults regardless of treatment condition, which suggests the importance of careful medication monitoring. Higher baseline use of alcohol and cannabis was associated with an increased risk of experiencing a treatment-related AE in OROS-MPH, but baseline use did not increase the risk of serious AEs or of any particular category of AE and the adolescents did not experience more treatment-related AEs relative to the adults.
Conclusions: With good monitoring, and in the context of substance abuse treatment, OROS-MPH can be safely used in adolescents with an SUD despite non-abstinence.
Related protocols: CTN-0028, CTN-0029
Attention deficit hyperactivity disorder (ADHD) is a neuropsychiatric condition subclassified in the DSM-IV according to its core symptom domains as (a) predominantly inattentive (ADHD-IN), (b) predominantly hyperactive/impulsive (ADHD-H), and (c) combined inattentive and hyperactive/impulsive (ADHD-C). Whether these subtypes represent distinct clinical entities or points on a severity continuum is controversial. Divergence in treatment response is a potential indicator of qualitative heterogeneity. This study, an ancillary investigation of data from protocol CTN-0029 (“A Pilot Study of Osmotic-Release Methylphenidate in Initiating and Maintaining Abstinence in Smokers with ADHD”), examined smoking cessation response by ADHD subtype to osmotic-release oral system methylphenidate (OROS-MPH). The analysis found that the subtypes were similar in baseline demographic, smoking, and psychiatric history, but differed in smoking cessation response to OROS-MPH or placebo as a function of nicotine dependence level. Among highly dependent smokers, the prolonged abstinence rates were greater with OROS-MPH than with placebo in the ADHD-C group, but higher with placebo than with OROS-MPH in the ADHD-IN group. Abstinence rates did not differ by subtype or treatment among smokers who were less nicotine dependent. Contrasting treatment response and divergence in the impact of nicotine dependence level support the hypothesis of ADHD subtypes as distinct clinical entities and may indicate the need and directions for personalized targeted treatments of smokers with ADHD.
Related protocols: CTN-0029