Psychiatric Annals

Original Research 

The Characteristics and Unique Impairments of Comorbid Adult ADHD and Sluggish Cognitive Tempo: An Interim Analysis

Michael J. Silverstein, BA; Terry L. Leon, MS, RN; Beth Krone, PhD; Stephen V. Faraone, PhD; Jeffrey H. Newcorn, MD; Lenard A. Adler, MD

Abstract

The objective of this study was to identify the relationship between sluggish cognitive tempo (SCT) symptoms and symptoms of attention-deficit/hyperactivity disorder (ADHD), executive function (EF), and emotional dyscontrol. A referred sample of adults (N = 87, age 18–57 years) was assessed for symptoms of ADHD using the Adult ADHD Investigator Symptom Rating Scale (AISRS), Barkley SCT scale, and Behavior Rating Inventory of Executive Function - Adult version (BRIEF-A), and for symptoms of impairment using the Clinical Global Impressions scale and Barkley Functional Impairment Scale. Adults with SCT and ADHD had greater inattention and impairment than adults with ADHD only. Also, the group with both SCT and ADHD had higher self-reported ratings of EF on the BRIEF-A, which was not evident on the clinician ratings of EF on the AISRS. The results show that adults with comorbid SCT and ADHD have greater symptoms of inattention and higher levels of impairment in this preliminary analysis. [Psychiatr Ann. 2019;49(10)457–465.]

Abstract

The objective of this study was to identify the relationship between sluggish cognitive tempo (SCT) symptoms and symptoms of attention-deficit/hyperactivity disorder (ADHD), executive function (EF), and emotional dyscontrol. A referred sample of adults (N = 87, age 18–57 years) was assessed for symptoms of ADHD using the Adult ADHD Investigator Symptom Rating Scale (AISRS), Barkley SCT scale, and Behavior Rating Inventory of Executive Function - Adult version (BRIEF-A), and for symptoms of impairment using the Clinical Global Impressions scale and Barkley Functional Impairment Scale. Adults with SCT and ADHD had greater inattention and impairment than adults with ADHD only. Also, the group with both SCT and ADHD had higher self-reported ratings of EF on the BRIEF-A, which was not evident on the clinician ratings of EF on the AISRS. The results show that adults with comorbid SCT and ADHD have greater symptoms of inattention and higher levels of impairment in this preliminary analysis. [Psychiatr Ann. 2019;49(10)457–465.]

Sluggish cognitive tempo (SCT) describes people who are “dreamy,” “spacey,” slow moving, hypoactive, have difficulty initiating tasks, and often seem under-motivated and under-aroused. For example, in a population sample of 1,249 adults with and without attention-deficit/hyperactivity disorder (ADHD), and with and without SCT, Barkley1 identified nine cardinal symptoms of SCT: (1) prone to daydreaming instead of concentrating; (2) trouble staying alert/awake in boring situations; (3) being easily confused; (4) being easily bored; (5) feeling spacey/in a fog; (6) frequently feeling lethargic; (7) being underactive/having less energy than others; (8) being slow moving; and (9) not processing information quickly/accurately. In his study, participants were identified as having SCT if they had at least 5 of 9 symptoms rated as “often” or “very often” on the 9-item SCT subscale from the Barkley Adult ADHD Rating Scale-IV: Self-Report (BAARS-IV: the Barkley SCT scale).2 The prevalence rate of SCT was 5.8%, and one-half of those meeting criteria for SCT also had ADHD. Studies have also shown that ADHD patients with SCT have substantial impairment.3,4 Based on these data, a number of authors have suggested that SCT may be a clinically meaningful condition not restricted to ADHD, with distinct underlying pathophysiology and treatment response.1,3,5 Becker et al.6 recently published a meta-analysis and critical review of the construct of SCT in children and adults, in which they found support for the internal validity of the construct as well as evidence that SCT is statistically, and potentially diagnostically, distinct from ADHD.

The few treatment studies of SCT in patients with ADHD to date have focused on children rather than adults. One naturalistic treatment trial of methylphenidate in children with ADHD and SCT found that the response for SCT symptoms was lower than for core ADHD symptoms.7 A post hoc analysis of a study of the selective norepinephrine reuptake inhibitor (and nonstimulant) atomoxetine versus placebo in children with ADHD and dyslexia versus dyslexia alone found that controlling for changes in ADHD scores did not significantly influence changes in SCT scores.8 However, lacking randomized clinical trial data in adults with ADHD with and without SCT, the responsivity of SCT symptoms to stimulant therapy remains unknown. The current study is a two-site (New York University and Icahn School of Medicine at Mount Sinai), two-phase study of the correlates of SCT in adults with ADHD that will also assess the treatment responsivity of adults with ADHD and SCT to the sustained-release stimulant lisdexamfetamine. We report an analysis of 87 patients examined in the baseline phase of this project from the NYU cohort to examine how the profiles of patients with and without SCT and with adult ADHD might differ.

Methods

Participants

A total of 120 participants consented to the study, of which 87 were eligible and completed the full screening and assessment phase of the study. One patient consented twice, as his consent needed to be repeated to ensure timing of medication availability for the second phase of the trial. Of the remaining 32 patients who consented but who did not proceed with the trial, the reasons for dropping from the study were as follows: (1) lack of adequate documentation of impairment on the ADHD Adult Clinical Diagnostic Scale version 1.2 (ACDS v1.2) or Barkley Functional Impairment Scale (BFIS) (n = 19), (2) presence of other significant mental health disorder that, in the judgment of the investigator, compromised participation (n = 9), (3) presence of current suicidal ideation (n = 1) and (4) investigator judgment that prior history or medical history would preclude study participation (n = 3).

Assessment

Participants were administered the Mini International Neuropsychiatric Interview 7.0 (MINI) to screen for psychiatric comorbidities listed in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5),9 the expanded Adult ACDS v1.2 to assess DSM-5 adult ADHD and measure symptom severity, the Behavior Rating Inventory of Executive Function - Adult version (BRIEF-A) to measure executive functioning, the BFIS, and Clinical Global Impression (CGI) scale to measure impairment, and the Barkley SCT Scale1 to measure the severity of SCT. Suicidality was assessed using the Columbia-Suicide Severity Rating Scale. Medical and psychiatric histories, as well as demographics, were self-reported.

All clinical assessments were administered in person by either board-certified psychiatrists, a clinical psychologist, or a research nurse, each of whom had at least 10 years of experience in adult ADHD research. All clinicians had been trained per standard procedures before initiation of the study.10 All diagnostic or clinical questions were discussed with two experts in adult ADHD (L. A. A. and J. H. N.).

Inclusion/Exclusion Criteria

Inclusion criteria were as follows: (1) man or woman between ages 18 and 60 years; (2) met DSM-5 criteria for a primary diagnosis of inattentive or combined type ADHD as diagnosed via ACDS v1.2; (3) demonstrated significant impairment, determined based on the norms of the BFIS; (4) the group with SCT was required to have 5 or more items on the Barkley SCT Scale rated 3 (“often”) or 4 (“very often”), and a total SCT symptom score of 26 or higher; in addition, the group with SCT must have had a T-score of 65 or higher on the Metacognition Index Subscale of BRIEF-A; and (5) the group without SCT had fewer than 5 items on the Barkley SCT Scale rated 3 (“often”) or 4 (“very often”), and a total SCT symptom score of less than 26; in addition patients without SCT must have had a T-score of less than 65 on the Metacognition Index of the BRIEF-A.

Participants were excluded if they (1) met DSM-5 criteria for a primary diagnosis of hyperactive-impulsive type ADHD as diagnosed via the ACDS v1.2; (2) had any other current psychiatric disorder, determined via the MINI, that requires pharmacotherapy treatment; (3) had current suicidal ideation or a history of suicide attempts; (4) had a lifetime history of bipolar disorder or any psychotic disorder as per the MINI; (5) were pregnant, breast-feeding, or female and planning to become pregnant; (6) had a positive urine drug toxicology screen at baseline; (7) had any other clinical or contextual issues that, in the opinion of the investigator (including a history of sleep disorders), would prevent the person from participating in the study or compromise the participant's safety; and (8) had previously used lisdexamfetamine (as that was the study drug).

The study was approved by the Institutional Review Board Associates of New York University Langone School of Medicine.

Rating Scales

ACDS v1.2.ADHD diagnosis was evaluated with v1.2 of the ACDS,11,12 a semi-structured diagnostic interview that is widely used in adult ADHD studies.13,14 The ACDS v1.2 clinical interview begins with an assessment of childhood symptoms of ADHD and then an expanded set of recent (past year) symptoms, including all DSM-5 criterion A1 and A2 symptoms. The scale includes developmentally relevant prompts and stem questions designed to capture DSM symptoms of ADHD as they present in childhood and adulthood. Based on the responses from the participant, the administering clinician rates the symptom severity as 1 (never), 2 (mild), 3 (moderate), or 4 (severe).

The ACDS v1.2 has been expanded to include additional symptoms intended to assess executive function deficits (EFDs; 9 items) and emotional dyscontrol (ED; 4 items). ED includes behavioral descriptors of mood lability, irritability, and emotional over-reactivity. As with the DSM-5 items, specific prompts have been written for the ACDS v1.2 EFD and ED items to help guide the rater in exploring developmentally relevant manifestations of ADHD.

Adult ADHD Investigator Rating Scale. For the baseline ratings, ACDS v1.2 scores were converted to Adult ADHD Investigator Rating Scale (AISRS) scores to measure ADHD symptom severity, as has been done in prior adult ADHD analyses.15,16 Both the ACDS v1.2 and AISRS use the same prompts and a 4-point scale (“none/never,” “mild,” “moderate” and “severe;” the latter two being the cutoff for clinical impairment for each item). Previous studies16 have established the rationale for this transformation, primarily based on the high agreement between AISRS and ACDS v1.2 scores and the importance of minimizing patient burden. Therefore, all subsequent discussion of ADHD symptom rating data will refer to the AISRS scores obtained from the ACDS v1.2 ratings.

The AISRS provides an ADHD total symptom score, as well as inattentive and hyperactive-impulsive subscale scores. These scales have been used to evaluate baseline symptoms in both cross-sectional and treatment studies.12,17–22

The BRIEF-A. The BRIEF-A23 was used to assess EFDs. The BRIEF-A is comprised of nine clinical subscales designed to measure various aspects of EF (eg, task monitoring, inhibition, organization) that make up the Metacognition Index (MCI) and the Behavioral Regulation Index (BRI). These two indexes make up the overall Global Executive Complex (GEC), which serves as a general measure of EF. The GEC, BRI, and MCI (as well as the subscales) have been standardized and T-scores can be used to describe the severity of impairment.

MINI 7.0. The MINI was used to evaluate psychiatric comorbidity.24,25 The MINI is structured on clinical interview used to assess DSM-5 psychiatric disorders and has been widely used to evaluate psychiatric comorbidity in adult ADHD studies.14,26–28

Functional Impairment Rating Scale. The Functional Impairment Rating Scale is a self-rated measurement of perceived current impairment in 15 different major life activities using a 10-point Likert scale (0 = not impaired, 9 = severely impaired).29 The activity domains include interactions at home, completing chores, activities, and work, social interactions, and relationships with friends. Mean impairment ratings can be calculated to quantify impairment.

CGI. Overall impairment was also assessed by the CGI Severity (CGI-S) scale, a widely used clinician rated measure of global ADHD impairment that uses a 7-point Likert rating (1 = normal, 7 = among the most severely ill patients).30

Barkley SCT Scale. Adult SCT was assessed using the SCT subscale of the Barkley Adult ADHD Rating Scale (BAARS)-IV.1 This is a 9-item self-report that is scored on a 3-point rating scale (1 = “never or rarely,” 2 = “sometimes,” 3 = “often” and “very often,” with the latter two being the cutoff for clinical impairment for each item). To qualify as having SCT requires 5 or more items rated as “often” or “very often,” as well as a total score of 26 or higher. The scale has been shown to have good psychometrics, including test-retest reliability.1 The Cronbach's alpha of the BAARS was .83 for this sample.

Data Analysis

Statistical analyses were conducted using SPSS version 24. Demographics and descriptive features of the total sample and for the SCT-positive and SCT-negative subsamples are presented. Pearson chi-square analyses were used to examine the association of categorical variables. Spearman correlations (Spearman's rho) examined the correlations among continuous variables. To determine if participants differed based on SCT status, a series of t tests of independent samples was conducted. Levene's test was conducted for each t test to confirm the assumption of equal variances. Unequal variances were assumed when Levene's test was violated. All tests were two-tailed and used a significance level of P < .05 unless indicated.

Results

Demographic Characteristics of the Total Sample

Demographics and ADHD symptom ratings, EFD ratings, and impairment for the sample are presented in Table 1. Most of the sample met criteria for the combined ADHD presentation. The sample was 61.9% (n = 53) white, 16.1% (n = 14) black, 14.9% Asian (n = 13), 2.3% (n = 2) American Indian or Alaskan Native, and 5.7% (n = 5) other/unknown. Nine participants (10.3%) had a lifetime mood or anxiety disorder. We found no significant associations between SCT status and lifetime mood/anxiety disorder (chi-square[1] = 0.47, P = .507, phi = 0.07); self-identification as Hispanic/Latino (chi-square[1] = 2.13, P =.145, phi = 0.15); or gender (chi-square[1] = 0.84, P = .360, phi = 0.10). However, there was a significant relationship between SCT diagnostic status and race (white compared to other races) (chi-square[1] = 4.19, P = .041, Cramer's V = 0.04), with there being a greater proportion of white participants (73.7%, n = 28) in the SCT-negative sample compared to the SCT-positive sample (52.1%, n =25).

Sample Demographics

Table 1:

Sample Demographics

Correlations Between ADHD Symptoms and EFD and ED Behavioral Descriptors

Spearman correlations between ADHD symptoms, EFDs, impairment ratings, and age are presented in Table 2. Age was not significantly correlated with ADHD severity, EFDs, ED, or impairment (all P values > .05). SCT severity score was weakly correlated with inattention (IA) severity (r = .22) and was significantly related to EFDs as measured on the BRIEF-A (rs = .21 to .34). Impairment as measured by the CGI and BFIS had small to large correlations with ADHD symptom severity, SCT severity, and EFDs (Spearman's rho = .19 to .66).

Spearman Correlations Between Measures of Attention–Deficit/Hyperactivity Disorder, Executive Functioning, and Sluggish Cognitive Tempo

Table 2:

Spearman Correlations Between Measures of Attention–Deficit/Hyperactivity Disorder, Executive Functioning, and Sluggish Cognitive Tempo

Comparing Samples of Patients With and Without SCT

Differences in ADHD symptoms, EFDs, ED symptoms, and impairment as assessed by t tests of independent samples are presented in Table 3. The SCT-positive sample had significantly greater IA severity: t(1,65) = 2.16, P = .034, d = 0.48. EFDs as measured by the BRIEF-A Global Executive Composite (GEC) and MCI were statistically significant different (P values = .007 to .002; ds = 0.53–0.71). However, there was no significant difference between the SCT-positive and SCT-negative samples in the EFDs as measured by clinician report on the AISRS (t[1,85] = 1.50, P = .137, d = 0.33).

Comparisons of ADHD, Executive Functioning, Emotional Dyscontrol, and Impairment Symptoms of Adults with ADHD Only to Adults with ADHD and Comorbid SCT

Table 3:

Comparisons of ADHD, Executive Functioning, Emotional Dyscontrol, and Impairment Symptoms of Adults with ADHD Only to Adults with ADHD and Comorbid SCT

Discussion and Conclusions

Adults with SCT and ADHD had significantly greater clinician-reported inattentive symptoms on the AISRS, self-reported executive function (EF) symptoms on the BRIEF-A, and higher impairment scores on a clinician global measure (CGI-S) and on a self-report functional impairment measure (BFIS) than adults with ADHD but without SCT. In contrast to the findings on the BRIEF-A, significantly higher clinician-reported EF symptoms were not seen on the AISRS in the comparisons of the groups with and without SCT. Clinician ratings of ED symptoms were significantly higher on the AISRS, but not on the self-report BRIEF-A in the SCT-positive versus SCT-negative cohorts.

The finding of significantly higher inattentive symptoms and greater levels of global ADHD symptoms and functional impairment in SCT-positive versus SCT-negative adult patients with ADHD is the most salient finding in these interim analyses. It is not likely that it is just higher presence of ADHD symptoms in general that is causing the higher levels of impairment in the SCT-positive group, as their total level of ADHD symptoms did not significantly differ on the AISRS versus the total symptom level in the SCT-negative cohort. It is not possible in the current analyses to know the relative contributions of SCT and inattentive symptoms to the observed higher levels of impairment in the SCT-positive group. We intend to further examine the potential contributions of inattentive and SCT symptoms to higher levels of impairment via multiple regression analyses if these relationships are observed again in analyses of the entire combined sample from this trial.

Of note, the idea that IA and SCT may represent different albeit correlated domains is supported by findings that IA and SCT predict different functional outcomes, and that they have differing relationships with predicting internalizing and externalizing behaviors.6,31 Additionally, although some prior studies have found a weak but significant association between hyperactive-impulsive symptoms and SCT ratings,4,32 the present study did not find any such association in adults with ADHD.

The finding that adults with ADHD and SCT had elevations in EF, as operationalized by ratings on the GEC and MCI subscales, and ratings of ED, is in line with past research. For example, Barkley1,5 found elevations in EF and ED in adults with SCT, but not in children. Based on this, it is possible that, when SCT presents or persists into adulthood it results in selective EF deficits that are not yet evident or have not yet developed in children.

Study Limitations

Limitations of the present study include the small sample size and the lack of a comparison group with SCT and without ADHD, both of which may have skewed our findings. Another potential confound was the requirement for a significantly elevated metacognition T-Score on the BRIEF-A. We chose this approach as a way to enrich the sample for EFD on potential neuropsychiatric psychometric tests, which will be reported when the data on the full sample are reported. The elevation of the metacognition score thus could create a potential confound to SCT findings; however, the current sample is not large enough to co-vary for this factor. We will examine potential confounds of the requirement of elevated metacognition score on the full data sample in subsequent analyses.

Additionally, the study only included self-reported SCT behavioral descriptors and not clinical ratings or informant ratings. Recent research suggests that the inclusion of informant ratings of SCT behaviors captures additional information.4 Additionally, our clinical interviews did not include reports from other informants (eg, spouse or friend), which could have improved accuracy of SCT measurement.33,34 Lastly, the present study did not include performance-based neuropsychological tests and only included self-reported and clinically rated EF, which assess different features of EF.35 Nevertheless, our approach informs us of the ways in which EF deficits manifest themselves in clinically significant behavioral outcomes (eg, difficulty with organization, poor inhibition). The importance of EF symptoms in children with SCT was highlighted by McBurnett et al.36 who found that working memory problems were a separate factor of SCT in a study of expanded symptoms in 165 children. Future articles with the full sample will include performance-based neuropsychological tests that will help elucidate the relationship of EFD and SCT and examine the role of working memory in our adult cohorts.

Conclusion

Regardless of these limitations, the present article extends the observations of SCT and EFD to adults and highlights the relationship of SCT and inattentive symptoms of adult ADHD, which has previously only been researched in children. These findings offer a basis for future analyses to be conducted on the full data set.

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Sample Demographics

Demographic Item N % Male % Hispanic DSM-5 Dx M (SD, Range)
Age AISRS DSM Item Total AISRS IA AISRS H-I AISRS EFD AISRS ED BARRS SCT Score GEC T-Score MCI T-Score BRI T-Score BFIS MI CGI
Total subsample 87 33.3 23.3 IA = 16% Comb. = 84% 32.4 y (8.4, 18.5–57.7) 38.7 (6.9, 18–51) 21.3 (3.1, 11–26) 17.3 (5.0, 3–25) 20.5 (3.7, 12–27) 5.4 (3.3, 0–12) 25.3 (5.7, 12–36) 74.5 (9.4, 48–98) 78.1 (9, 51–98) 65.5 (11.9, 40–90) 5.7 (1.1, 1.07–8) 4.7 (0.6, 4–6)
With SCT 48 29.2 29.2 IA = 17% Comb: = 83% - 39.7 (6.3, 24–49) 22.0 (2.5, 14–26) 17.7 (4.9, 3–25) 21.1 (4.0, 13–27) 6.2 (2.6, 1–12) 29.5 (2.7, 26–36) 76.9 (8.7, 56–98) 80.8 (8.2, 60–98) 67.0 (11.7, 43–89) 6.2 (0.8, 4.7–8) 4.8 (0.6, 4–6)
Without SCT 39 38.5 15.4 IA = 15% Comb: = 85% 27 y (7.5, 18–51) 37.5, (7.6, 18–51) 20.5 (3.7, 11–26) 16.9 (5.2, 425) 19.9 (3.3, 12–25) 4.5 (3.7, 0–12) 20.3 (3.6, 12–25) 71.5 (9.4, 48–92) 74.7 (9.0, 51–89) 63.5 (11.9, 40–90) 5.2 (1.2, 1.1–7.9) 4.5 (0.6, 4–6)

Spearman Correlations Between Measures of Attention–Deficit/Hyperactivity Disorder, Executive Functioning, and Sluggish Cognitive Tempo

Measure 1 2 3 4 5 6 7 8 9 10 11 12 13
1 Age -
2 BAARS SCT score .02 -
3 SCT diagnosis .12 .86a -
4 18-item (IA + H–I) severity .13 .18b .18b -
5 IA severity .14 .22c .23c .76a -
6 H-I severity .15 .07 .08 .88a .42a -
7 EFDs severity −.12 .18b .17b .50a .60a .29d -
8 ED severity .01 .24c .24c .09 .14 .02 .30d -
9 BRIEF-A GEC T-score .12 .31c .29d .33d .29b .20b .27c .28c -
10 BRIEF-A MCI T-score .16 .34a .33d .27b .33c .11 .16 .08 .83a -
11 BRIEF-A BRI T-score .04 .21b .15 .26c .13 .20b .19b .39a .82a .41a -
12 CGI .08 .19b .23c .66a .64a .49a .41a .02 .37a .33c .28c -
13 BFIS MIS .01 .36a .42a .32c .28b .26b .29*d .26b .31d .27b .25b .34a -

Comparisons of ADHD, Executive Functioning, Emotional Dyscontrol, and Impairment Symptoms of Adults with ADHD Only to Adults with ADHD and Comorbid SCT

Scale/Measure df t P Cohen's d
AISRS DSM 18-item total 1,85 1.48 .141 0.32
AISRS IA 1,65a 2.16 .034 0.48
AISRS H-I 1,85 0.66 .510 0.16
AISRS EFD 1,85 1.50 .137 0.33
AISRS ED 1,66a 2.30 .023 0.53
GEC T-score 1,85 2.77 .007 0.60
MCI T-score 1,85 3.27 .002 0.71
BRI T-score 1,85 1.37 .176 0.30
BFIS 1,85 4.65 <.001 0.98
CGI 1,85 2.16 .034 0.50
Authors

Michael J. Silverstein, BA, is a Doctoral Candidate, Department of Psychology, Drexel University; and a per diem Research Data Associate, Department of Psychiatry, New York University School of Medicine. Terry L. Leon, MS, RN, is a Senior Clinical Research Coordinator, Department of Psychiatry, New York University School of Medicine. Beth Krone, PhD, is an Assistant Professor, Department of Psychiatry, Icahn School of Medicine at Mount Sinai. Stephen V. Faraone, PhD, is a Professor and Vice Chair for Research, Departments of Psychiatry and of Neuroscience and Physiology, SUNY Upstate Medical University. Jeffrey H. Newcorn, MD, is a Professor, Department of Psychiatry, Icahn School of Medicine at Mount Sinai. Lenard A. Adler, MD, is a Vice-Chair, CME, Professor, Department of Psychiatry; a Professor, Department of Child and Adolescent Psychiatry; and the Director, Adult ADHD Program, New York University School of Medicine.

Address correspondence to Lenard A. Adler, MD, Department of Psychiatry and Child and Adolescent Psychiatry, New York University School of Medicine, One Park Avenue, 8th Floor, New York, NY 10016; email: lenard.adler@nyulangone.org.

Grant: Funding for this trial was provided by an investigator-initiated (L.A.A. and J.H.N.) grant (NCT02635035) from Shire Pharmaceuticals awarded to New York University; Mt. Sinai (B.K. and J.H.N) was funded through a subcontract from New York University.

Disclosure: Stephen V. Faraone reports that he receives income, potential income, travel expenses, continuing education support and/or research support from Ironshore, Shire, Akili, Enzymotec, Sunovion, and Genomind; previously received support from Neuorvance, Alcobra, Rhodes, Cogcubed, KemPharm, Neurolifesciences, Lundbeck/Takeda, Otsuka, McNeil, Janssen, Novartis, Pfizer, and Eli Lilly; receives royalites from Guilford Press and Oxford University Press; and receives grant support from the European Union's Seventh Framework Programme for Research, the European Union's Horizon 2020 Research and Innovation Programme, the National Institute of Mental Health. Jeffrey H. Newcorn reports he is/has been an advisor and/or consultant for Adlon Therapeutics, Akili Interactive, Alcobra, Arbor, Cingulate Therapeutics, Enzymotec, KemPharm, Lundbeck/Takeda, Medice, NLS, Rhodes, Shire, and Supernus; a Data and Safety Monitoring Board member for Pfizer and Sunovion; received research funds from Enzymotec, Otsuka, Shire, and Supernus; received speaker fees from Shire for disease-state presentations; and served as a consultant for the US National Football League. Lenard A. Adler is a consultant for Shire, Otsuka, Enzymotec, Sunovion, Bracket, Alcobra, Major League Baseball, the National Football League, Rhodes, and the State University of New York; receives grants from Sunovion, Lunbeck, Enzymotec; and royalty payments from New York Univesity School of Medicine for scales and training material for adult attention-deficit/hyperactivity disorders. The remaining authors have no relevant financial relationships to disclose.

The authors thank Amanda Kirschenbaum (Mount Sinai), Daniela Barrera (NYU), Sarah Laury (NYU), and Jonathan Yuh (NYU) for assistance with data collection and entry; Glenn Hirsch, MD (NYU) for his help in the conduct of the trial; and Russell Barkley, PhD (Virginia Commenwealth University School of Medicine) for his assistance in interpretation of the findings.

10.3928/00485713-20190905-01

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