In Memoriam: Professor Joseph Biederman's Contributions to Child and Adolescent Psychiatry

OBJECTIVE

To provide an overview of Joe Biederman's contributions to child and adolescent psychiatry.

METHOD

Nine colleagues described his contributions to: psychopharmacology, comorbidity and genetics, pediatric bipolar disorder, autism spectrum disorders, Tourette's and tic disorders, clinical and neuro biomarkers for pediatric mood disorders, executive functioning, and adult ADHD.

RESULTS

Joe Biederman left us with many concrete indicators of his contributions to child and adolescent psychiatry. He set up the world's first pediatric psychopharmacology clinic and clinical research program in child adolescent psychiatry. As a young faculty member he began a research program that led to many awards and eventual promotion to full professor at Harvard Medical School. He was for many years the most highly cited researcher in ADHD. He achieved this while maintaining a full clinical load and was widely respected for his clinical acumen.

CONCLUSION

The world is a better place because Joe Biederman was here.

Preclinical Models of Attention Deficit Hyperactivity Disorder: Neurobiology, Drug Discovery, and Beyond

OBJECTIVE

We offer an overview of ADHD research using mouse models of nicotine exposure.

METHOD

Nicotine exposure of C57BL/6 or Swiss Webster mice occurred during prenatal period only or during the prenatal and the pre-weaning periods. Behavioral, neuroanatomical and neurotransmitter assays were used to investigate neurobiological mechanisms of ADHD and discover candidate ADHD medications.

RESULTS

Our studies show that norbinaltorphimine, a selective kappa opioid receptor antagonist is a candidate novel non-stimulant ADHD treatment and that a combination of methylphenidate and naltrexone has abuse deterrent potential with therapeutic benefits for ADHD. Other studies showed transgenerational transmission of ADHD-associated behavioral traits and demonstrated that interactions between untreated ADHD and repeated mild traumatic brain injury produced behavioral traits not associated with either condition alone.

CONCLUSION

Preclinical models contribute to novel insights into ADHD neurobiology and are valuable tools for drug discovery and translation to benefit humans with ADHD.

Editorial: Height and Stimulant Treatment in Attention-Deficit/Hyperactivity Disorder Youth: Mind the Gap

In this issue of the Journal, the important story of height and weight issues related to stimulant medication in attention-deficit/hyperactivity disorder (ADHD) is yet again addressed, in the largest study to date.1 Controversy related to potential growth decrements in youth with ADHD receiving stimulants has been around for decades. In fact, in a quick PubMed search of the literature, we identified more than 100 studies, 15 reviews, and meta-analyses in this area. In a general score card, about three-fourths of studies seem to support some degree of decrement, but clinical significance has yet to be determined. What is not being debated anymore is the short- and longer-term effectiveness of stimulants for ADHD with reductions in mood disorders, suicide, substance use/disorders, criminality, motor vehicle accidents, injuries, concussions, and academic failure documented in the Swedish and other register studies.2 Many of these improvements are linked with a decrease in major morbidity and even mortality. Hence, we need to put the issue of potential stimulant-related growth velocity changes in the context of the very real adverse outcomes associated with non-treatment of ADHD.

Frontal Cortical Monoamine Release, Attention, and Working Memory in a Perinatal Nicotine Exposure Mouse Model Following Kappa Opioid Receptor Antagonism

Perinatal nicotine exposure (PNE) produces frontal cortical hypo-dopaminergic state and attention and working memory deficits consistent with neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD). Methylphenidate alleviates ADHD symptoms by increasing extracellular dopamine and noradrenaline. Kappa opioid receptor (KOR) antagonism may be another mechanism to achieve the same results because KOR activation inhibits frontal cortical dopamine release. We administered the selective KOR antagonist norbinaltorphimine (norBNI) (20 mg/kg; intraperitoneal) or methylphenidate (0.75 mg/kg; intraperitoneal) to PNE mouse model and examined frontal cortical monoamine release, attention, and working memory. Both compounds increased dopamine and noradrenaline release but neither influenced serotonin release. Both compounds improved object-based attention and working memory in the PNE group, with norBNI's effects evident at 2.5 h and 5.5 h but absent at 24 h. Methylphenidate's effects were evident at 0.5 h but not at 2.5 h. norBNI's effects temporally coincided with frontal cortical c-Jun N-terminal kinase phosphorylation. norBNI did not alter tissue dopamine content in the nucleus accumbens, offering preliminary support for lack of reinforcement.

Comparative effectiveness of prolonged exposure and cognitive processing therapy for military service members in an intensive treatment program

OBJECTIVE

While the comparative efficacy of prolonged exposure (PE) and cognitive processing therapy (CPT) has been examined in outpatient settings, there is a dearth of literature on the relative effectiveness of these interventions when adapted for an intensive treatment format. In an expanded secondary analysis of a previous study, we sought to examine the comparative effectiveness of PE and CPT delivered in the naturalistic setting of an intensive treatment format including maintenance of outcomes through a 6-month follow-up period.

METHOD

A sample of 296 veterans with posttraumatic stress disorder (PTSD) received either PE (n = 186) or CPT (n = 90), alongside other trauma-informed interventions, in a 2-week intensive clinical program. Treatment selection was determined collaboratively between patient and therapist. Our primary outcome was self-reported PTSD symptom severity (i.e., PTSD Checklist for DSM-5, PCL-5); secondarily, we examined self-reported depression (i.e., Patient Health Questionnaire) symptom severity outcomes.

RESULTS

A mixed-model regression controlling for age and gender revealed a significant effect of time from baseline to endpoint (p < .001), 3-month (p < .001), and 6-month follow-up (p < .001) on PCL-5 scores but no significant effect of treatment or effect of treatment by time interaction (all ps > .05; model: Wald's χ² = 232.38, p < .001). Results were similar for depression outcomes. Attrition at posttreatment was not significantly different between groups: 7.2% for CPT and 6.5% PE (z score = 0.22).

CONCLUSIONS

Both PE and CPT are associated with comparable improvements when delivered as part of a 2-week intensive outpatient program. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Is Paternal Smoking at Conception a Risk for ADHD? A Controlled Study in Youth With and Without ADHD

Objective: Based on emerging preclinical findings suggesting that paternal smoking at conception may be a risk for ADHD in the offspring, we investigated whether a similar effect can be observed in humans. Method: We analyzed data from an opportunistic dataset of girl probands with (N = 140) and without (N = 122) ADHD with available information on paternal smoking at conception. Data were analyzed using Pearson's chi-square tests and multiple logistic regression. Results: ADHD probands had a significantly higher rate of paternal smoking at conception than controls (35% vs. 23%, χ² = 3.82, p = .05) with a significant odds ratio of 1.5. However, the association lost significance after controlling for paternal ADHD, most likely due to limited statistical power. Conclusion: While preliminary, findings suggest that paternal smoking at conception may be a risk factor for ADHD in the offspring.

Transgenerational transmission of behavioral phenotypes produced by exposure of male mice to saccharin and nicotine

The use of non-nutritive sweeteners such as saccharin is widely prevalent. Although saccharin is considered safe for human consumption, it produces behavioral changes in experimental animals. We report that saccharin’s behavioral effects are much more pervasive than currently recognized. In a mouse model, saccharin exposure produced motor impulsivity not only in the saccharin-exposed males but also in their offspring. In addition, the offspring showed locomotor hyperactivity and working memory deficit not observed in fathers. Spermatazoal DNA was hypermethylated in the saccharin-exposed fathers, especially at dopamine receptor promoter regions, suggesting that epigenetic modification of germ cell DNA may mediate transgenerational transmission of behavioral phenotypes. Dopamine’s role in hyperactivity was further highlighted by the finding that the stimulant drug methylphenidate mitigated the hyperactivity. Nicotine is another substance that is widely used. Its use via smokeless tobacco products, some of which contain saccharin, is on the rise contributing to concerns about adverse outcomes of co-exposure to saccharin and nicotine. We found that co-exposure of male mice to saccharin and nicotine produced significant behavioral impairment in their offspring. Thus, our data point to potential adverse neurobehavioral consequences of exposure to saccharin alone or saccharin and nicotine for the exposed individuals and their descendants.

Toward operationalizing deficient emotional self-regulation in newly referred adults with ADHD: A receiver operator characteristic curve analysis

Background.

A growing body of research suggests that deficient emotional self-regulation (DESR) is common and morbid among attention-deficit/hyperactivity disorder (ADHD) patients. The main aim of the present study was to assess whether high and low levels of DESR in adult ADHD patients can be operationalized and whether they are clinically useful.

Methods.

A total of 441 newly referred 18- to 55-year-old adults of both sexes with Diagnostic and Statistical Manual of Mental Disorders: Fifth Edition (DSM-5) ADHD completed self-reported rating scales. We operationalized DESR using items from the Barkley Current Behavior Scale. We used receiver operator characteristic (ROC) curves to identify the optimal cut-off on the Barkley Emotional Dysregulation (ED) Scale to categorize patients as having high- versus low-level DESR and compared demographic and clinical characteristics between the groups.

Results.

We averaged the optimal Barkley ED Scale cut-points from the ROC curve analyses across all subscales and categorized ADHD patients as having high- (N = 191) or low-level (N = 250) DESR (total Barkley ED Scale score ≥8 or <8, respectively). Those with high-level DESR had significantly more severe symptoms of ADHD, executive dysfunction, autistic traits, levels of psychopathology, and worse quality of life compared with those with low-level DESR. There were no major differences in outcomes among medicated and unmedicated patients.

Conclusions.

High levels of DESR are common in adults with ADHD and when present represent a burdensome source of added morbidity and disability worthy of further clinical and scientific attention.

Informativeness of Self-Reports of ADHD Symptoms in Monitoring Response to Stimulant Treatment in Clinically Referred Adults With ADHD

Objective: To investigate the informativeness of self-reports of ADHD symptoms in adults with ADHD in the clinical setting. Method: Subjects were clinically referred adults aged 19 years to 67 years of age of both sexes (N = 54). All subjects were on stable doses of stimulant and were considered responders to treatment. ADHD symptoms were assessed using the ADHD Investigator Symptom Rating Scale (AISRS) and the ADHD Self-Report Scale (ASRS). Spearman's rank correlations were used to assess the correlations between clinician-assessed ADHD and patients' self-reports. Results: Spearman's rank correlation analysis found evidence of a strong, positive association between total scores on the AISRS and the ASRS (rs = .65, df = 52, p< .001). Conclusion: Results have important implications for the management and monitoring of treatment response in the clinical setting through patients' self-report.

Collaborative Songwriting Intervention for Veterans with Post-Traumatic Stress Disorder

Objectives: Given that veterans are significantly more likely to suffer from post-traumatic stress disorder (PTSD), traumatic brain injury (TBI), depression, and anxiety than civilians, yet current gold-standard treatments for PTSD are not effective for all patients, the present study sought to examine the feasibility and acceptability of a collaborative songwriting intervention (CSI) while exploring its potential effectiveness in improving physical and mental health outcomes for veterans with PTSD. Design: Ten veterans took part in the CSI. A variety of pre- and postintervention measures were administered, including the Measurement of Current Status (MOCS), the Coping Expectancies Scale (CES), the Post-traumatic Stress Disorder Checklist-Military (PCL-M), and the Patient Health Questionnaire-9 (PHQ-9). Participants also wore a Fitbit to track average heart rate, sleep, and step count. Intervention: The CSI consisted of each veteran meeting with a professional songwriter, trained specifically for co-writing original material with the veteran population. There were three phases of songwriting that took about an hour and 15 min total. Veterans were instructed to listen to their song daily for 5 weeks. Results: Participants reported that the intervention was helpful and relevant to them, and most participants (95%) would refer others to this treatment. We found that the CSI reduced participant's PTSD symptoms (d = 0.869), specifically the Numbing (d = 0.853) and Hyperarousal (d = 1.077) subscales. Depressive symptoms (d = 0.72) and stress reactivity (d = 0.785) also marginally decreased. There was no significant change in physiological data (i.e., sleep, no. of steps) from pre- to postintervention. Conclusion: These data suggest that a CSI is an acceptable intervention for veterans with PTSD that may also improve their PTSD symptoms.

Acceptability of an adjunct equine-assisted activities and therapies program for veterans with posttraumatic stress disorder and/or traumatic brain injury

OBJECTIVE

Equine-assisted activities and therapies (EAATs) have been a growing adjunctive integrative health modality, as they allow participants to practice mindfulness, emotional regulation, and self-mastery or self-esteem building skills. Preliminary evidence suggests that these programs may be helpful in reducing posttraumatic stress disorder (PTSD), anxiety, and depressive symptoms. The current study examines the acceptability of integrating an EAAT program as part of a two-week, intensive clinical program for veterans with PTSD and/or traumatic brain injury (TBI).

METHODS

A family member or support person could accompany veterans and participate in the program. One hundred and six participants (veteran n = 62, family n = 44) left the urban environment in an intensive outpatient program (IOP) to attend a two-day, weekend EAAT in rural New Hampshire. Satisfaction surveys were conducted on the last day of the program and examined using thematic analysis.

RESULTS

The following themes were reported in the surveys: ability of horses to catalyze emotional rehabilitation, effectiveness of immersion in equine-assisted activities, program's ability to foster interpersonal relationships and necessity of education about PTSD for staff. Participants also reported enjoying the program as highlighted by qualitative feedback, a mean score of 9.76 (standard deviation [SD] = 0.61) as reported by veterans and a mean score of 9.91 (SD = 0.29) as reported by family members on a 10-point visual analog scale with higher scores indicating a greater overall experience.

CONCLUSION

These data offer preliminary evidence that an adjunct EAAT program is acceptable for veterans with PTSD and/or TBI participating in an IOP.

The Relationship Between Executive Function Deficits and DSM-5-Defined ADHD Symptoms

Objectives: To identify the relationship between the core Diagnostic and Statistical Manual of Mental Disorders (5th ed.) ADHD symptoms and executive function deficits (EFDs), to evaluate ADHD characteristics of those with executive dysfunction (ED), and to examine the predictive utility of the Adult ADHD Investigator Symptom Rating Scale (AISRS) in identifying those with adult ADHD and ED. Method: Two samples (referred and primary care practice) were pooled together for present analysis. Results: Final analysis included 297 respondents, 171 with adult ADHD. Spearman correlation coefficients and binary logistic regressions demonstrated that ADHD inattentive (IA) and hyperactive-impulsive (H-I) symptoms were moderately to strongly correlated with and highly predictive of EFDs. Receiver operating characteristic curve analysis showed that an AISRS DSM 18-item score of ⩾ 28 was most predictive of clinical ED. Conclusion: ADHD symptoms were strongly correlated with and predictive of EFDs, clinicians should screen adults with ADHD for EFDs and ADHD treatment providers should track EFD improvement in addition to DSM-5 ADHD symptoms.

Validation of the Expanded Versions of the Adult ADHD Self-Report Scale v1.1 Symptom Checklist and the Adult ADHD Investigator Symptom Rating Scale

Objective: The aim of this study is to validate the Adult ADHD Self-Report Scale (ASRS) and Adult ADHD Investigator Symptom Rating Scale (AISRS) expanded versions, including executive function deficits (EFDs) and emotional dyscontrol (EC) items, and to present ASRS and AISRS pilot normative data. Method: Two patient samples (referred and primary care physician [PCP] controls) were pooled together for these analyses. Results: Final analysis included 297 respondents, 171 with adult ADHD. Cronbach's alphas were high for all sections of the scales. Examining histograms of ASRS 31-item and AISRS 18-item total scores for ADHD controls, 95% cutoff scores were 70 and 23, respectively; histograms for pilot normative sample suggest cutoffs of 82 and 26, respectively. Conclusion: (a) ASRS- and AISRS-expanded versions have high validity in assessment of core 18 adult ADHD Diagnostic and Statistical Manual of Mental Disorders (DSM) symptoms and EFD and EC symptoms. (b) ASRS (31-item) scores 70 to 82 and AISRS (18-item) scores from 23 to 26 suggest a high likelihood of adult ADHD.

Dasotraline in Children with Attention-Deficit/Hyperactivity Disorder: A Six-Week, Placebo-Controlled, Fixed-Dose Trial

OBJECTIVE

Dasotraline is a potent inhibitor of presynaptic dopamine and norepinephrine reuptake with a pharmacokinetic profile characterized by slow absorption and a long elimination half-life. The aim of this study was to evaluate the efficacy and safety of dasotraline in children with attention-deficit/hyperactivity disorder (ADHD).

METHODS

Children aged 6-12 years with a Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnosis of ADHD were randomized to 6 weeks of double-blind once-daily treatment with dasotraline (2 or 4 mg) or placebo. The primary efficacy endpoint was change from baseline in the ADHD Rating Scale Version IV-Home Version (ADHD RS-IV HV) total score at week 6.

RESULTS

A total of 342 patients were randomized to dasotraline or placebo (mean age 9.1 years, 66.7% male). Treatment with dasotraline was associated with significant improvement at study endpoint in the ADHD RS-IV HV total score for the 4 mg/day dose versus placebo (-17.5 vs. -11.4; p < 0.001; effect size [ES], 0.48), but not for the 2 mg/day dose (-11.8 vs. -11.4; ns; ES, 0.03). A regression analysis confirmed a significant linear dose-response relationship for dasotraline. Significant improvement for dasotraline 4 mg/day dose versus placebo was also observed across the majority of secondary efficacy endpoints, including the Clinical Global Impression (CGI)-Severity score, the Conners Parent Rating Scale-Revised scale (CPRS-R) ADHD index score, and subscale measures of hyperactivity and inattentiveness. Discontinuation rates due to adverse events (AEs) were higher in the dasotraline 4 mg/day group (12.2%) compared with the 2 mg/day group (6.3%) and placebo (1.7%). The most frequent AEs associated with dasotraline were insomnia, decreased appetite, decreased weight, and irritability. Psychosis-related symptoms were reported as AEs by 7/219 patients treated with dasotraline in this study. There were no serious AEs or clinically meaningful changes in blood pressure or heart rate on dasotraline.

CONCLUSION

In this placebo-controlled study, treatment with dasotraline 4 mg/day significantly improved ADHD symptoms and behaviors, including attention and hyperactivity, in children aged 6-12 years. The most frequently reported AEs observed on dasotraline included insomnia, decreased appetite, decreased weight, and irritability.

A General Framework for Assessing In vitro/In vivo Correlation as a Tool for Maximizing the Benefit-Risk Ratio of a Treatment Using a Convolution-Based Modeling Approach

The net benefit of a treatment can be defined by the relationship between clinical improvement and risk of adverse events: the benefit‐risk ratio. The optimization of the benefit‐risk ratio can be achieved by identifying the most adequate dose (and/or dosage regimen) jointly with the best‐performing in vivo release properties of a drug. A general in silico tool is presented for identifying the dose, the in vitro and the in vivo release properties that maximize the benefit‐risk ratio using convolution‐based modeling, an exposure‐response model, and a surface response analysis. A case study is presented to illustrate how the benefit‐risk ratio of methylphenidate for the treatment of attention deficit hyperactivity disorder can be maximized using the proposed strategy. The results of the analysis identified the characteristics of an optimized dose and in vitro/in vivo release suitable to provide a sustained clinical response with respect to the conventional dosage regimen and formulations.

Nicotine exposure of male mice produces behavioral impairment in multiple generations of descendants

Use of tobacco products is injurious to health in men and women. However, tobacco use by pregnant women receives greater scrutiny because it can also compromise the health of future generations. More men smoke cigarettes than women. Yet the impact of nicotine use by men upon their descendants has not been as widely scrutinized. We exposed male C57BL/6 mice to nicotine (200 μg/mL in drinking water) for 12 wk and bred the mice with drug-naïve females to produce the F1 generation. Male and female F1 mice were bred with drug-naïve partners to produce the F2 generation. We analyzed spontaneous locomotor activity, working memory, attention, and reversal learning in male and female F1 and F2 mice. Both male and female F1 mice derived from the nicotine-exposed males showed significant increases in spontaneous locomotor activity and significant deficits in reversal learning. The male F1 mice also showed significant deficits in attention, brain monoamine content, and dopamine receptor mRNA expression. Examination of the F2 generation showed that male F2 mice derived from paternally nicotine-exposed female F1 mice had significant deficits in reversal learning. Analysis of epigenetic changes in the spermatozoa of the nicotine-exposed male founders (F0) showed significant changes in global DNA methylation and DNA methylation at promoter regions of the dopamine D2 receptor gene. Our findings show that nicotine exposure of male mice produces behavioral changes in multiple generations of descendants. Nicotine-induced changes in spermatozoal DNA methylation are a plausible mechanism for the transgenerational transmission of the phenotypes. These findings underscore the need to enlarge the current focus of research and public policy targeting nicotine exposure of pregnant mothers by a more equitable focus on nicotine exposure of the mother and the father.

Sport concussion and attention deficit hyperactivity disorder in student athletes: A cohort study

Background

Attention deficit hyperactivity disorder (ADHD) is associated with impulsive behavior and inattention, making it a potential risk factor for sport-related concussion (SRC). The objectives of this study were to determine whether ADHD is an antecedent risk factor for SRC and whether ADHD complicates recovery from SRC in youth athletes.

Methods

Student athletes with a history of SRC were evaluated for the presence of ADHD using diagnostic interview and to determine whether ADHD symptoms began before or after SRC. Concussion-specific measures of concussive symptoms and cognitive function were compared in SRC + ADHD and SRC + No ADHD groups to assess SRC recovery between groups.

Results

ADHD was overrepresented in youth with SRC compared with population rates. ADHD was found to be an antecedent risk factor for SRC, with age at ADHD onset earlier than the date of SRC. Student athletes with SRC and ADHD reported more concussive symptoms compared with athletes without ADHD and were more likely to have a history of greater than one concussion.

Conclusions

The results of this study support our hypothesis that ADHD is an antecedent risk factor for SRC and may contribute to a more complicated course of recovery from SRC. Future research should focus on determining whether screening, diagnosis, and treating ADHD in youth athletes may prevent SRC. Providers that care for youth athletes with ADHD should be aware of the vulnerabilities of this population toward SRC and its complications.

A Familial Risk Analysis of Emotional Dysregulation: A Controlled Study

OBJECTIVE

Children with deficits in emotional regulation operationalized by scores on the Child Behavior Checklist (CBCL) Attention Problems, Aggressive Behavior, and Anxious-Depressed subscales are more likely than others to manifest adverse outcomes. However, the transmission of this profile has not been well studied. The main aim of this study was to investigate the familiality of this profile.

METHOD

Participants were youth probands with bipolar I (BP-I) disorder ( N = 140), ADHD ( N = 83), and controls ( N = 117) and their siblings. Based on the CBCL emotional dysregulation profile, we classified children with severe emotional dysregulation (aggregate cut-off score ≥210) and emotional dysregulation (aggregate cut-off score ≥ 180 and <210).

RESULTS

Emotional dysregulation profile scores correlated positively between probands and siblings.

CONCLUSION

Youth with emotional dysregulation are at increased risk to have siblings with similar deficits, suggesting that emotional dysregulation runs in families.

How Informative Are Self-Reported Adult Attention-Deficit/Hyperactivity Disorder Symptoms? An Examination of the Agreement Between the Adult Attention-Deficit/Hyperactivity Disorder Self-Report Scale V1.1 and Adult Attention-Deficit/Hyperactivity Disorder Investigator Symptom Rating Scale

OBJECTIVES

Assess agreement between self-ratings via the adult attention-deficit/hyperactivity disorder (ADHD) Self-Report Scale (ASRS)-v1.1 Symptom Checklist and clinician ratings via the adult ADHD Investigator Symptom Rating Scale (AISRS) expanded version using DSM-5 adult ADHD patients (referred sample) and ADHD controls (recruited from a primary care physician practice).

METHODS

The ASRS v1.1 Symptom Checklist was administered to measure self-reported ADHD symptoms and impairment, the Adult ADHD Clinical Diagnostic Scale v1.2 was used to establish an adult ADHD diagnosis and the childhood and adult/current sections of the scale were used to provide scores to measure symptoms of childhood ADHD and recent symptoms of adult ADHD, the AISRS to measure ADHD current symptom severity.

RESULTS

Participants (n = 299; range 18-58), of which 171 were ADHD+ and 128 ADHD-. ASRS and AISRS total scores and individual subsections examining inattention, hyperactivity, emotional dysfunction (EF), and emotional dyscontrol (EC) were all significantly correlated (Spearman's ρ's = 0.78-0.89, ps < 0.01). Correlations remained significant when controlling for demographic factors and psychiatric conditions.

CONCLUSIONS

The ASRS (self) and AISRS (clinician rated) scales have high agreement. This agreement extended not only the to the core 18 DSM symptoms, but also to the additional 13 symptoms that examine EC and EF.

Attention and working memory deficits in a perinatal nicotine exposure mouse model

BACKGROUND

Cigarette smoking by pregnant women is associated with a significant increase in the risk for cognitive disorders in their children. Preclinical models confirm this risk by showing that exposure of the developing brain to nicotine produces adverse behavioral outcomes. Here we describe behavioral phenotypes resulting from perinatal nicotine exposure in a mouse model, and discuss our findings in the context of findings from previously published studies using preclinical models of developmental nicotine exposure.

METHODOLOGY/PRINCIPAL FINDINGS

Female C57Bl/6 mice received drinking water containing nicotine (100μg/ml) + saccharin (2%) starting 3 weeks prior to breeding and continuing throughout pregnancy, and until 3 weeks postpartum. Over the same period, female mice in two control groups received drinking water containing saccharin (2%) or plain drinking water. Offspring from each group were weaned at 3-weeks of age and subjected to behavioral analyses at 3 months of age. We examined spontaneous locomotor activity, anxiety-like behavior, spatial working memory, object based attention, recognition memory and impulsive-like behavior. We found significant deficits in attention and working memory only in male mice, and no significant changes in the other behavioral phenotypes in male or female mice. Exposure to saccharin alone did not produce significant changes in either sex.

CONCLUSION/SIGNIFICANCE

The perinatal nicotine exposure produced significant deficits in attention and working memory in a sex-dependent manner in that the male but not female offspring displayed these behaviors. These behavioral phenotypes are associated with attention deficit hyperactivity disorder (ADHD) and have been reported in other studies that used pre- or perinatal nicotine exposure. Therefore, we suggest that preclinical models of developmental nicotine exposure could be useful tools for modeling ADHD and related disorders.

Adult Outcome of ADHD: An Overview of Results From the MGH Longitudinal Family Studies of Pediatrically and Psychiatrically Referred Youth With and Without ADHD of Both Sexes

OBJECTIVE

We aimed to provide an overview of the Massachusetts General Hospital (MGH) Longitudinal Studies of ADHD.

METHODS

We evaluated and followed samples of boys and girls with and without ADHD ascertained from psychiatric and pediatric sources and their families.

RESULTS

These studies documented that ADHD in both sexes is associated with high levels of persistence into adulthood, high levels of familiality with ADHD and other psychiatric disorders, a wide range of comorbid psychiatric and cognitive disorders including mood, anxiety, and substance use disorders, learning disabilities, executive function deficits, emotional dysregulation, and autistic traits as well as functional impairments. The MGH studies suggested that stimulant treatment decreased risks of developing comorbid psychiatric disorders, substance use disorders, and functional outcomes. The MGH studies documented the neural basis of persistence of ADHD using neuroimaging.

CONCLUSION

The MGH studies provided various insights on symptoms, course, functions, comorbidities, and neuroscience of ADHD.

Opiate Antagonists Do Not Interfere With the Clinical Benefits of Stimulants in ADHD: A Double-Blind, Placebo-Controlled Trial of the Mixed Opioid Receptor Antagonist Naltrexone

OBJECTIVE

Methylphenidate activates μ-opioid receptors, which are linked to euphoria. μ-Opioid antagonists, such as naltrexone, may attenuate the euphoric effects of stimulants, thereby minimizing their abuse potential. This study assessed whether the combination of naltrexone with methylphenidate is well-tolerated while preserving the clinical benefits of stimulants in subjects with attention-deficit/hyperactivity disorder (ADHD).

METHODS

We conducted a 6-week, double-blind, placebo-controlled, randomized clinical trial of naltrexone in adults with DSM-IV ADHD receiving open treatment with a long-acting formulation of methylphenidate from January 2013 to July 2015. Spheroidal Oral Drug Absorption System (SODAS) methylphenidate was administered twice daily, was titrated to approximately 1 mg/kg/d over 3 weeks, and was continued for 3 additional weeks depending on response and adverse effects. Subjects were adults with ADHD preselected for having experienced euphoria with a test dose of immediate-release methylphenidate. The primary outcome measure was the Adult ADHD Investigator Symptom Report Scale (AISRS).

RESULTS

Thirty-seven subjects who experienced stimulant-induced (mild) euphoria at a baseline visit were started in the open trial of SODAS methylphenidate and randomly assigned to naltrexone 50 mg or placebo. Thirty-one subjects completed the study through week 3, and 25 completed through week 6. Throughout 6 weeks of blinded naltrexone and open methylphenidate treatment, the coadministration of naltrexone with methylphenidate did not interfere with the clinical effectiveness of methylphenidate for ADHD symptoms. Additionally, the combination of naltrexone and methylphenidate did not produce an increase in adverse events compared with methylphenidate alone.

CONCLUSIONS

Our findings provide support for the concept of combining opioid receptor antagonists with stimulants to provide an effective stimulant formulation with less abuse potential.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01673594​.

The Mixed Opioid Receptor Antagonist Naltrexone Mitigates Stimulant-Induced Euphoria: A Double-Blind, Placebo-Controlled Trial of Naltrexone

OBJECTIVE

Supratherapeutic doses of methylphenidate activate μ-opioid receptors, which are linked to euphoria. This study assessed whether naltrexone, a mixed μ-opioid antagonist, may attenuate the euphoric effects of stimulants, thereby minimizing their abuse potential in subjects with attention-deficit/hyperactivity disorder (ADHD).

METHODS

We conducted a 6-week, double-blind, placebo-controlled, randomized clinical trial of naltrexone in adults with DSM-IV ADHD receiving open treatment with a long-acting formulation of methylphenidate (January 2013 to June 2015). Spheroidal Oral Drug Absorption System methylphenidate (SODAS-MPH) was administered twice daily, was titrated to ~1 mg/kg/d over 3 weeks, and was continued for 3 additional weeks depending on response and adverse effects. Subjects were adults with ADHD preselected for having experienced euphoria with an oral test dose of 60 mg of immediate-release methylphenidate (IR-MPH). The primary outcome measure was Question 2 (Liking a Drug Effect) on the Drug Rating Questionnaire, Subject version, which was assessed after oral test doses of 60 mg of IR-MPH were administered after the third and sixth weeks of treatment with SODAS-MPH.

RESULTS

Thirty-seven subjects who experienced stimulant-induced (mild) euphoria at a baseline visit were started in the open trial of SODAS-MPH and randomized to naltrexone 50 mg/d or placebo. Thirty-one subjects completed through week 3, and 25 completed through week 6. Naltrexone significantly diminished the euphoric effect of IR-MPH during the heightened-risk titration phase (primary outcome; first 3 weeks) (χ² = 5.07, P = .02) but not the maintenance phase (weeks 4-6) (χ² = 0.22, P = .64) of SODAS-MPH treatment.

CONCLUSIONS

Preclinical findings are extended to humans showing that naltrexone may mitigate stimulant-associated euphoria. Our findings provide support for further studies combining opioid receptor antagonists with stimulants to reduce abuse potential.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01673594.

Is Maternal Smoking During Pregnancy a Risk Factor for Cigarette Smoking in Offspring? A Longitudinal Controlled Study of ADHD Children Grown Up

OBJECTIVE

This study examined whether exposure to maternal smoking during pregnancy in children with and without ADHD is associated with smoking in offspring and whether this association is selective to ADHD children.

METHOD

Ninety-six exposed and 400 unexposed participants were derived from two longitudinal studies of boys and girls with and without ADHD. Maternal smoking during pregnancy was defined by interviews with participants' mothers.

RESULTS

A significant association was observed between exposure to maternal smoking in pregnancy and cigarette smoking in offspring ( p = .02). Exposed offspring were also more likely to have higher rates of major depression ( p = .04), bipolar disorder ( p = .04), and conduct disorder ( p = .04), and lower IQ ( p = .01), lower Global Assessment of Functioning (GAF) score ( p = .02), and more impaired Social Adjustment Inventory for Children and Adolescents (SAICA) scores versus unexposed offspring, adjusting for social class.

CONCLUSION

Maternal smoking during pregnancy was found to increase the risk for smoking and a wide range of adverse psychiatric, cognitive, and functional outcomes in youth.

Model-Based Approach for Optimizing Study Design and Clinical Drug Performances of Extended-Release Formulations of Methylphenidate for the Treatment of ADHD

Methylphenidate (MPH) is currently used to treat children with attention deficit hyperactivity disorder (ADHD). Several extended-release (ER) formulations characterized by a dual release process were developed to improve efficacy over an extended duration. In this study, a model-based approach using literature data was developed to: 1) evaluate the most efficient pharmacokinetic (PK) model to characterize the complex PK profile of MPH ER formulations; 2) provide PK endpoint metrics for comparing ER formulations; 3) define criteria for optimizing development of ER formulations using a convolution-based model linking in vitro release, in vivo release, and hour-by-hour behavioral ratings of ADHD symptoms; and 4) define an optimized trial design for assessing the activity of MPH in pediatric populations. The convolution-based model accurately described the complex PK profiles of a variety of ER MPH products, providing a natural framework for establishing an in vitro/in vivo correlation and for defining criteria for assessing comparative bioequivalence of MPH ER products.

The World Health Organization Adult Attention-Deficit/Hyperactivity Disorder Self-Report Screening Scale for DSM-5

Importance

Recognition that adult attention-deficit/hyperactivity disorder (ADHD) is common, seriously impairing, and usually undiagnosed has led to the development of adult ADHD screening scales for use in community, workplace, and primary care settings. However, these scales are all calibrated to DSM-IV criteria, which are narrower than the recently developed DSM-5 criteria.

Objectives

To update for DSM-5 criteria and improve the operating characteristics of the widely used World Health Organization Adult ADHD Self-Report Scale (ASRS) for screening.

Design, Setting, and Participants

Probability subsamples of participants in 2 general population surveys (2001-2003 household survey [n = 119] and 2004-2005 managed care subscriber survey [n = 218]) who completed the full 29-question self-report ASRS, with both subsamples over-sampling ASRS-screened positives, were blindly administered a semistructured research diagnostic interview for DSM-5 adult ADHD. In 2016, the Risk-Calibrated Supersparse Linear Integer Model, a novel machine-learning algorithm designed to create screening scales with optimal integer weights and limited numbers of screening questions, was applied to the pooled data to create a DSM-5 version of the ASRS screening scale. The accuracy of the new scale was then confirmed in an independent 2011-2012 clinical sample of patients seeking evaluation at the New York University Langone Medical Center Adult ADHD Program (NYU Langone) and 2015-2016 primary care controls (n = 300). Data analysis was conducted from April 4, 2016, to September 22, 2016.

Main Outcomes and Measures

The sensitivity, specificity, area under the curve (AUC), and positive predictive value (PPV) of the revised ASRS.

Results

Of the total 637 participants, 44 (37.0%) household survey respondents, 51 (23.4%) managed care respondents, and 173 (57.7%) NYU Langone respondents met DSM-5 criteria for adult ADHD in the semistructured diagnostic interview. Of the respondents who met DSM-5 criteria for adult ADHD, 123 were male (45.9%); mean (SD) age was 33.1 (11.4) years. A 6-question screening scale was found to be optimal in distinguishing cases from noncases in the first 2 samples. Operating characteristics were excellent at the diagnostic threshold in the weighted (to the 8.2% DSM-5/Adult ADHD Clinical Diagnostic Scale population prevalence) data (sensitivity, 91.4%; specificity, 96.0%; AUC, 0.94; PPV, 67.3%). Operating characteristics were similar despite a much higher prevalence (57.7%) when the scale was applied to the NYU Langone clinical sample (sensitivity, 91.9%; specificity, 74.0%; AUC, 0.83; PPV, 82.8%).

Conclusions and Relevance

The new ADHD screening scale is short, easily scored, detects the vast majority of general population cases at a threshold that also has high specificity and PPV, and could be used as a screening tool in specialty treatment settings.

Abnormal fear circuitry in Attention Deficit Hyperactivity Disorder: A controlled magnetic resonance imaging study

We examined whether non-traumatized subjects with Attention Deficit Hyperactivity Disorder (ADHD) have dysfunctional activation in brain structures mediating fear extinction, possibly explaining the statistical association between ADHD and other disorders characterized by aberrant fear processing such as PTSD. Medication naïve, non-traumatized young adult subjects with (N=27) and without (N=20) ADHD underwent a 2-day fear conditioning and extinction protocol in a 3T functional magnetic resonance imaging (fMRI) scanner. Skin conductance response (SCR) was recorded as a measure of conditioned response. Compared to healthy controls, ADHD subjects had significantly greater insular cortex activation during early extinction, lesser dorsal anterior cingulate cortex (dACC) activation during late extinction, lesser ventromedial prefrontal cortex (vmPFC) activation during late extinction learning and extinction recall, and greater hippocampal activation during extinction recall. Hippocampal and vmPFC deficits were similar to those documented in PTSD subjects compared to traumatized controls without PTSD. Non-traumatized, medication naive adults with ADHD had abnormalities in fear circuits during extinction learning and extinction recall, and some findings were consistent with those previously documented in subjects with PTSD compared to traumatized controls without PTSD. These findings could explain the significant association between ADHD and PTSD as well as impaired emotion regulation in ADHD.

The structure of adult ADHD

Although DSM-5 stipulates that symptoms of attention-deficit hyperactivity disorder (ADHD) are the same for adults as children, clinical observations suggest that adults have more diverse deficits than children in higher-level executive functioning and emotional control. Previous psychometric analyses to evaluate these observations have been limited in ways addressed in the current study, which analyzes the structure of an expanded set of adult ADHD symptoms in three pooled US samples: a national household sample, a sample of health plan members, and a sample of adults referred for evaluation at an adult ADHD clinic. Exploratory factor analysis found four factors representing executive dysfunction/inattention (including, but not limited to, all the DSM-5 inattentive symptoms, with non-DSM symptoms having factor loadings comparable to those of DSM symptoms), hyperactivity, impulsivity, and emotional dyscontrol. Empirically-derived multivariate symptom profiles were broadly consistent with the DSM-5 inattentive-only, hyperactive/impulsive-only, and combined presentations, but with inattention including executive dysfunction/inattention and hyperactivity-only limited to hyperactivity without high symptoms of impulsivity. These results show that executive dysfunction is as central as DSM-5 symptoms to adult ADHD, while emotional dyscontrol is more distinct but nonetheless part of the combined presentation of adult ADHD.

The Neuropsychological Profile of Comorbid Post-Traumatic Stress Disorder in Adult ADHD

OBJECTIVE

ADHD and post-traumatic stress disorder (PTSD) are often comorbid yet despite the increased comorbidity between the two disorders, to our knowledge, no data have been published regarding the neuropsychological profile of adults with comorbid ADHD and PTSD. Likewise, previous empirical studies of the neuropsychology of PTSD did not control for ADHD status. We sought to fill this gap in the literature and to assess the extent to which neuropsychological test performance predicted psychosocial functioning, and perceived quality of life.

METHOD

Participants were 201 adults with ADHD attending an outpatient mental health clinic between 1998 and 2003 and 123 controls without ADHD. Participants completed a large battery of self-report measures and psychological tests. Diagnoses were made using data obtained from structured psychiatric interviews (i.e., Structured Clinical Interview for DSM-IV, Schedule for Affective Disorders and Schizophrenia for School-Age Children Epidemiologic Version).

RESULTS

Differences emerged between control participants and participants with ADHD on multiple neuropsychological tests. Across all tests, control participants outperformed participants with ADHD. Differences between the two ADHD groups emerged on seven psychological subtests including multiple Wechsler Adult Intelligence Scale-Third edition and Rey-Osterrieth Complex Figure Test measures. These test differences did not account for self-reported quality of life differences between groups.

CONCLUSION

The comorbidity with PTSD in adults with ADHD is associated with weaker cognitive performance on several tasks that appear related to spatial/perceptual abilities and fluency. Neuropsychological test performances may share variance with the quality of life variables yet are not mediators of the quality of life ratings.

Local membrane length conservation in two-dimensional vesicle simulation using a multicomponent lattice Boltzmann equation method

We present a method for applying a class of velocity-dependent forces within a multicomponent lattice Boltzmann equation simulation that is designed to recover continuum regime incompressible hydrodynamics. This method is applied to the problem, in two dimensions, of constraining to uniformity the tangential velocity of a vesicle membrane implemented within a recent multicomponent lattice Boltzmann simulation method, which avoids the use of Lagrangian boundary tracers. The constraint of uniform tangential velocity is carried by an additional contribution to an immersed boundary force, which we derive here from physical arguments. The result of this enhanced immersed boundary force is to apply a physically appropriate boundary condition at the interface between separated lattice fluids, defined as that region over which the phase-field varies most rapidly. Data from this enhanced vesicle boundary method are in agreement with other data obtained using related methods [e.g., T. Krüger, S. Frijters, F. Günther, B. Kaoui, and J. Harting, Eur. Phys. J. 222, 177 (2013)10.1140/epjst/e2013-01834-y] and underscore the importance of a correct vesicle membrane condition.

Examining the association between posttraumatic stress disorder and attention-deficit/hyperactivity disorder: a systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review and meta-analysis examining the relationship between attention-deficit/hyperactivity disorder (ADHD) and posttraumatic stress disorder (PTSD).

DATA SOURCES

We reviewed literature through PubMed and PsycINFO without a specified date range, utilizing the search (posttraumatic stress disorder OR PTSD) AND (ADHD OR attention deficit hyperactivity disorder OR ADD OR attention deficit disorder OR hyperkinetic syndrome OR minimal brain dysfunction). References from relevant articles were reviewed.

STUDY SELECTION

We identified 402 articles; 28 met criteria. We included original human research in English that operationalized diagnoses of ADHD and PTSD, evaluated the relationship between the disorders, and included controls. We excluded articles that failed to differentiate ADHD or PTSD from nonspecific or subsyndromal deficits or failed to compare their relationship.

DATA EXTRACTION

We extracted sample size, age, diagnostic methods, design, referral status, control type, and number of subjects with and without ADHD and PTSD alone and combined. We computed meta-analyses for 22 studies examining ADHD in PTSD and PTSD in ADHD using a random effects model and meta-analytic regression. We assessed for heterogeneity and publication bias and adjusted for intrastudy clustering.

RESULTS

The relative risk (RR) for PTSD in ADHD was 2.9 (P < .0005); in samples using healthy controls, the RR was 3.7 (P = .001); and in samples using traumatized controls, the RR was 1.6 (P = .003). The RR for ADHD in PTSD was 1.7 (P < .0005); in samples using traumatized controls, the RR was 2.1 (P < .0005). The association was not significant in samples using psychiatric controls.

CONCLUSIONS

Results indicate a bidirectional association between ADHD and PTSD, suggesting clinical implications and highlighting the need for neurobiological research that examines the mechanisms underlying this connection.

Toward Defining the Neural Substrates of ADHD: A Controlled Structural MRI Study in Medication-Naïve Adults

OBJECTIVE

We assessed the neural correlates of adult ADHD in treatment-naïve participants, an approach necessary for identifying neural substrates unconfounded by medication effects.

METHOD

The sample consisted of 24 medication-naïve adults with Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) diagnosed ADHD and 24 healthy controls, comparable on age, sex, handedness, reading achievement, IQ, and psychiatric comorbidity. All participants were assessed with structured diagnostic interviews. Magnetic resonance imaging (MRI)-based regional voxel-based morphometry (r-VBM) was used to assess volumetric differences in a priori defined brain regions of interest.

RESULTS

VBM analysis revealed group differences in the hypothesized cortical and subcortical areas; however, only cerebellar volume reductions in ADHD retained significance (p < .05) after corrections for multiple comparisons.

CONCLUSION

These results support the notion that medication-naïve ADHD as expressed in adulthood, manifests subtle brain volume reductions from normal in the cerebellum, and possibly in other syndrome-congruent gray-matter structures. Larger samples are required to confirm these findings.

Mild traumatic brain injury and ADHD: a systematic review of the literature and meta-analysis

OBJECTIVE

This study investigated the association between mild traumatic brain injury (mTBI) and ADHD, which increases risk of injuries and accidents.

METHOD

We conducted a systematic review and meta-analysis of studies that examined the relationship between mTBI and ADHD.

RESULTS

Five studies, comprising 3,023 mTBI patients and 9,716 controls, fit our a priori inclusion and exclusion criteria. A meta-analysis found a significant association between ADHD and mTBI, which was significant when limited to studies that reported on ADHD subsequent to mTBI and when the direction of the association was not specified, but not for studies that reported mTBI subsequent to ADHD. Heterogeneity of effect size and publication biases were not evident.

CONCLUSION

The literature documents a significant association between mTBI and ADHD. Further clarification of the relationship and direction of effect between mTBI and ADHD and treatment implications could have large clinical, scientific, and public health implications.

Is ADHD a risk for posttraumatic stress disorder (PTSD)? Results from a large longitudinal study of referred children with and without ADHD

OBJECTIVES

Preclinical studies link prenatal nicotine exposure with the development of both ADHD-like phenotype in rodents and blockade of extinction learning in a fear conditioning paradigm, a preclinical model of posttraumatic stress disorder (PTSD). While these findings suggest that either ADHD, prenatal nicotine exposure, or both could be a risk factor for PTSD, such associations have not been investigated in humans.

METHODS

Subjects were ascertained from family-genetic, longitudinal studies of paediatrically and psychiatrically referred children with and without ADHD of both sexes and their siblings followed for 10 years from childhood into adulthood (n = 403 probands; n = 464 siblings; mean age at follow-up of probands and siblings = 22.0 years). All subjects were comprehensively evaluated with structured diagnostic interviews that included questions regarding prenatal use of cigarettes.

RESULTS

A total of 12% (104/867) of the sample had been exposed to maternal smoking during pregnancy. There was no interaction effect between maternal smoking during pregnancy and ADHD (z = 0.01, P = 0.99). Maternal smoking during pregnancy and ADHD were independent, significant risk factors for PTSD at the 10-year follow-up (odds ratio = 3.58 [1.35,9.48], z = 2.57, P = 0.01 and odds ratio = 2.23 [1.06,4.69], z = 2.11, P = 0.04, respectively).

CONCLUSIONS

These results suggest that both maternal smoking during pregnancy and ADHD are significant predictors of PTSD in humans.

Multicomponent lattice Boltzmann equation method with a discontinuous hydrodynamic interface

In the multicomponent lattice Boltzmann equation simulation method (MCLB), applied to the continuum regime of fluid flow, the finite width of the fluid-fluid interface introduces unphysical scales. We present a practical, robust, computationally efficient, and easy to implement solution to this problem which needs only low order interpolation to be stable and accurate and is applicable to any MCLB variant which uses a continuous phase field to distinguish between immiscible fluids with arrested coalescence. Our method extends the ideas of Kim and Pitsch, [Phys. Fluids 19, 108101 (2007)] and uses no external force distribution whatsoever to generate continuum interfacial physics, i.e., the Laplace law and no traction conditions on interfacial stresses. As such, it is amenable to the simplest form of Chapman-Enskog analysis used for lattice Boltzmann models. We assess our method and proceed to compare key results obtained with it against other equivalent data, obtained using the established continuum regime MCLB technique based upon the work of Lishchuk, Care, and Halliday, [Phys. Rev. E 67, 036701 (2003)] and Halliday, Hollis, and Care, [Phys. Rev. E 76, 026708 (2007)], quantifying performance in terms of the minimum feasible capillary available to simulation using that technique.

Effect of psychostimulants on brain structure and function in ADHD: a qualitative literature review of magnetic resonance imaging-based neuroimaging studies

OBJECTIVE

To evaluate the impact of therapeutic oral doses of stimulants on the brains of ADHD subjects as measured by magnetic resonance imaging (MRI)-based neuroimaging studies (morphometric, functional, spectroscopy).

DATA SOURCES

We searched PubMed and ScienceDirect through the end of calendar year 2011 using the keywords (1) psychostimulants or methylphenidate or amphetamine, and (2) neuroimaging or MRI or fMRI, and (3) ADHD or ADD or attention-deficit/hyperactivity disorder or attention deficit hyperactivity disorder.

STUDY SELECTION

We included only English language articles with new data from case-control or placebo controlled studies that examined attention-deficit/hyperactivity disorder (ADHD) subjects on and off psychostimulants (as well as 5 relevant review articles).

DATA EXTRACTION

We combined details of study design and medication effects in each imaging modality.

RESULTS

We found 29 published studies that met our criteria. These included 6 structural MRI, 20 functional MRI studies, and 3 spectroscopy studies. Methods varied widely in terms of design, analytic technique, and regions of the brain investigated. Despite heterogeneity in methods, however, results were consistent. With only a few exceptions, the data on the effect of therapeutic oral doses of stimulant medication suggest attenuation of structural and functional alterations found in unmedicated ADHD subjects relative to findings in controls.

CONCLUSIONS

Despite the inherent limitations and heterogeneity of the extant MRI literature, our review suggests that therapeutic oral doses of stimulants decrease alterations in brain structure and function in subjects with ADHD relative to unmedicated subjects and controls. These medication-associated brain effects parallel, and may underlie, the well-established clinical benefits.

Functional genomics of attention-deficit/hyperactivity disorder (ADHD) risk alleles on dopamine transporter binding in ADHD and healthy control subjects

BACKGROUND

The main aim of this study was to examine the relationship between dopamine transporter (DAT) binding in the striatum in individuals with and without attention-deficit/hyperactivity disorder (ADHD), attending to the 3'-untranslated region of the gene (3'-UTR) and intron8 variable number of tandem repeats (VNTR) polymorphisms of the DAT (SLC6A3) gene.

METHODS

Subjects consisted of 68 psychotropic (including stimulant)-naïve and smoking-naïve volunteers between 18 and 55 years of age (ADHD n = 34; control subjects n = 34). Striatal DAT binding was measured with positron emission tomography with 11C altropane. Genotyping of the two DAT (SLC6A3) 3'-UTR and intron8 VNTRs used standard protocols.

RESULTS

The gene frequencies of each of the gene polymorphisms assessed did not differ between the ADHD and control groups. The ADHD status (t = 2.99; p<.004) and 3'-UTR of SLC6A3 9 repeat carrier status (t = 2.74; p<.008) were independently and additively associated with increased DAT binding in the caudate. The ADHD status was associated with increased striatal (caudate) DAT binding regardless of 3'-UTR genotype, and 3'-UTR genotype was associated with increased striatal (caudate) DAT binding regardless of ADHD status. In contrast, there were no significant associations between polymorphisms of DAT intron8 or the 3'-UTR-intron8 haplotype with DAT binding.

CONCLUSIONS

The 3'-UTR but not intron8 VNTR genotypes were associated with increased DAT binding in both ADHD patients and healthy control subjects. Both ADHD status and the 3'-UTR polymorphism status had an additive effect on DAT binding. Our findings suggest that an ADHD risk polymorphism (3'-UTR) of SLC6A3 has functional consequences on central nervous system DAT binding in humans.

Examining the nature of the comorbidity between pediatric attention deficit/hyperactivity disorder and post-traumatic stress disorder

OBJECTIVE

This study sought to address the link between attention deficit/hyperactivity disorder (ADHD) and post-traumatic stress disorder (PTSD) in youth by providing a comprehensive comparison of clinical correlates of ADHD subjects with and without PTSD across multiple non-overlapping domains of functioning and familial patterns of transmission.

METHOD

Participants were 271 youths with ADHD and 230 controls without ADHD of both sexes along with their siblings. Participants completed a large battery of measures designed to assess psychiatric comorbidity, psychosocial, educational, and cognitive parameters.

RESULTS

Post-traumatic stress disorder was significantly higher in ADHD probands vs. controls (5.2% vs. 1.7%, χ(2) (1) = 4.36, P = 0.04). Irrespective of the comorbidity with PTSD, ADHD subjects had similar ages at onset of ADHD, similar type and mean number of ADHD symptoms, and similar ADHD-associated impairments. PTSD in ADHD probands was significantly associated with a higher risk of psychiatric hospitalization, school impairment, poorer social functioning and higher prevalences of mood, conduct disorder, and anxiety disorders. The mean onset of PTSD (12.6 years) was significantly later than that of ADHD and comorbid disorders (all P < 0.05). Siblings of ADHD and ADHD + PTSD probands had higher prevalences of ADHD vs. siblings of controls (35% vs. 18%, z = 4.00, P < 0.001 and 67% vs. 18%, z = 4.02, P < 0.001 respectively) and siblings of ADHD+PTSD probands had a significantly higher prevalence of PTSD compared with the siblings of ADHD and control probands (20% vs. 3% and 3%, z = 2.99, P = 0.003 and z = 2.07, P = 0.04 respectively).

CONCLUSION

Findings indicate that the comorbidity with PTSD in ADHD leads to greater clinical severity as regards psychiatric comorbidity and psychosocial dysfunction. ADHD is equally familial in the presence of PTSD in the proband indicating that their co-occurrence is not owing to diagnostic error.

Personal and familial correlates of bipolar (BP)-I disorder in children with a diagnosis of BP-I disorder with a positive child behavior checklist (CBCL)-severe dysregulation profile: a controlled study

BACKGROUND

Although the DSM-IV provides explicit criteria for the diagnosis of BP-I disorder, this is a complex diagnosis that requires high levels of clinical expertise. Previous work shows children with a unique profile of the CBCL of high scores (2SD) on the attention problems (AP), aggressive behavior (AGG), and anxious-depressed (AD) (A-A-A) subscales are more likely than other children to meet criteria for BP-I disorder in both epidemiological and clinical samples. However, since not all BP-I disorder children have a positive profile questions remain as to its informativeness, particularly in the absence of an expert diagnostician.

METHODS

Analyses were conducted comparing personal and familial correlates of BP-I disorder in 140 youth with a structured interview and an expert clinician based DSM-IV diagnosis of BP-I disorder with (N=80) and without (N=60) a positive CBCL- Severe Dysregulation profile, and 129 controls of similar age and sex without ADHD or a mood disorder. Subjects were comprehensively assessed with structured diagnostic interviews and wide range of functional measures. We defined the CBCL-severe dysregulation profile as an aggregate cut-off score of ≥ 210 on the A-A-A scales.

RESULTS

BP-I probands with and without a positive CBCL-severe dysregulation profile significantly differed from Controls in patterns of psychiatric comorbidity, psychosocial and psychoeducational dysfunction, and cognitive deficits, as well as in their risk for BP-I disorder in first degree relatives.

LIMITATIONS

Because the sample was referred and largely Caucasian, findings may not generalize to community samples and other ethnic groups.

CONCLUSION

A positive CBCL-severe dysregulation profile identifies a severe subgroup of BP-I disorder youth.

Posttraumatic stress disorder in adult attention-deficit/hyperactivity disorder: clinical features and familial transmission

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) is characterized by clinically significant functional impairment due to symptoms of inattention and/or hyperactivity and impulsivity. Previous research suggests a link, in child samples, between ADHD and posttraumatic stress disorder (PTSD), which is characterized by (1) chronically reexperiencing a traumatic event, (2) hyperarousal, and (3) avoiding stimuli associated with the trauma while exhibiting numbed responsiveness. This study sought to address the link between ADHD and PTSD in adults by providing a comprehensive comparison of ADHD patients with and without PTSD across multiple variables including demographics, patterns of psychiatric comorbidities, functional impairments, quality of life, social adjustment, and familial transmission.

METHOD

Participants in our controlled family study conducted between 1998 and 2003 were 190 adults with DSM-IV ADHD who were attending an outpatient mental health clinic in Boston, Massachusetts; 16 adults with DSM-IV ADHD who were recruited by advertisement from the greater Boston area; and 123 adult controls without ADHD who were recruited by advertisement from the greater Boston area. All available first-degree relatives also participated. Subjects completed a large battery of self-report measures (the Quality of Life Enjoyment and Satisfaction Questionnaire, items from the Current Behavior Scale, the Social Adjustment Scale Self-Report, and the Four Factor Index of Social Status) designed to assess various psychiatric and functional parameters. Diagnoses were made using data obtained from structured psychiatric interviews (Structured Clinical Interview for DSM-IV Axis I Disorders, Clinician Version, and the Schedule for Affective Disorders and Schizophrenia for School-Aged Children-Epidemiologic Version).

RESULTS

The lifetime prevalence of PTSD was significantly higher among adults with ADHD compared with controls (10.0% vs 1.6%; P = .004). Participants with ADHD and those with ADHD + PTSD did not differ in core symptoms of ADHD nor in age at onset, but those with ADHD + PTSD had higher rates of psychiatric comorbidity than those with ADHD only (including higher lifetime rates of major depressive disorder, oppositional defiant disorder, social phobia, agoraphobia, and generalized anxiety disorder) and worse quality of life ratings for all domains. Familial risk analysis revealed that relatives of ADHD probands without PTSD had elevated rates of both ADHD (51%) and PTSD (12%) that significantly differed from rates among relatives of controls (7% [P ≤ .001] and 0% [P ≤ .05], respectively). A similar pattern of elevated risk for ADHD and PTSD (80% and 40%) was observed in relatives of probands with ADHD + PTSD (P ≤ .001 for both conditions).

CONCLUSIONS

The comorbidity of PTSD and ADHD in adults leads to greater clinical severity in terms of psychiatric comorbidity and psychosocial functioning. The familial coaggregation of the 2 disorders suggests that these disorders share familial risk factors and that their co-occurrence is not due to diagnostic errors.

Multiple-component lattice Boltzmann equation for fluid-filled vesicles in flow

We document the derivation and implementation of extensions to a two-dimensional, multicomponent lattice Boltzmann equation model, with Laplace law interfacial tension. The extended model behaves in such a way that the boundary between its immiscible drop and embedding fluid components can be shown to describe a vesicle of constant volume bounded by a membrane with conserved length, specified interface compressibility, bending rigidity, preferred curvature, and interfacial tension. We describe how to apply this result to several, independent vesicles. The extended scheme is completely Eulerian, and it represents a two-way coupled vesicle membrane and flow within a single framework. Unlike previous methods, our approach dispenses entirely with the need explicitly to track the membrane, or boundary, and makes no use whatsoever of computationally expensive and intricate interface tracking and remeshing. Validation data are presented, which demonstrate the utility of the method in the simulation of the flow of high volume fraction suspensions of deformable objects.

Preliminary examination of the reliability and concurrent validity of the attention-deficit/hyperactivity disorder self-report scale v1.1 symptom checklist to rate symptoms of attention-deficit/hyperactivity disorder in adolescents

OBJECTIVE

To validate the attention-deficit/hyperactivity disorder (ADHD) Self-Report Scale (ASRS) v1.1 Symptom Checklist versus the clinician-administered ADHD Rating Scale (ADHD-RS) in adolescents with ADHD.

METHOD

A total of 88 adolescents with ADHD aged 13-17 years participated in the study. The study was completed in one or two visits, 1-9 weeks apart. At each visit, participants completed the ASRS v1.1 Symptom Checklist, after which raters administered the ADHD-RS. Internal consistency of the ASRS v1.1 Symptom Checklist was assessed by Cronbach's alpha (Cronbach's α). Concurrent validity between the scales was assessed using Pearson's correlation coefficients. Item-by-item reliability between the scales was assessed by the Kappa coefficient of agreement.

RESULTS

The mean age of participants was 14.9±1.5 SD years. 76.1% (n=67) were male. 73.9% (n=65) were currently receiving medication for ADHD. Internal consistency of ASRS v1.1 Symptom Checklist items was high, with Cronbach's α coefficients of 0.93 at Visit 1 and 0.94 at Visit 2. Pearson's correlation coefficients between the ASRS v1.1 Symptom Checklist and ADHD-RS were highly significant at Visit 1 (r=0.72, p<0.0001) and Visit 2 (r=0.73, p<0.0001). There was moderate item-by-item agreement between individual items on the scales (% agreement: 35.2%-63.4%) with statistically significant kappa coefficients for 17 of the 18 items.

CONCLUSION

The ASRS v1.1 Symptoms Checklist showed high internal consistency and high concurrent validity with the clinician-administered ADHD-RS in adolescents with ADHD. Results of this study suggest that the ASRS v1.1 Symptom Checklist is an internally consistent self-report scale for the assessment of adolescent ADHD and is moderately associated with a concurrently administered clinician measure of ADHD symptoms.

Importance of pharmacokinetic profile and timing of coadministration of short- and long-acting formulations of methylphenidate on patterns of subjective responses and abuse potential

OBJECTIVE

Subjective responses (ie, liking, disliking) to stimulants are thought to be proxies for abuse potential. Greater subjective responses have been documented in formulations that are more rapidly absorbed. However, repeat dosing has not been examined.

METHODS

Subjective responses on the Drug Rating Questionnaire were compared in 26 healthy adults after administration of short- (immediate-release [IR] methylphenidate [MPH]) and long- (osmotically controlled-release oral delivery system [OROS] MPH) acting stimulant formulations. The second dose was administered 4 hours after initial dosing. All subjects received all 5 conditions (ie, placebo to placebo; IR-MPH to IR-MPH; IR-MPH to OROS-MPH; OROS-MPH to IR-MPH; or OROS-MPH to OROS-MPH) in a double-blind, counter-balanced design on 5 separate days.

RESULTS

Plasma levels and subjective patterns of detection were higher when an IR formulation was administered during the ascending phase of a first-administered long-acting dose (OROS).

CONCLUSION

These results emphasize the critical role that formulation type (IR vs OROS) and timing of administration (ascending vs descending phase) play when short- and long-acting formulations are coadministered. Such knowledge provides important information for clinicians about the safety and tolerability of the timing of repeat dosing of various permutations of coadministration of MPH formulations.

Understanding the central pharmacokinetics of spheroidal oral drug absorption system (SODAS) dexmethylphenidate: a positron emission tomography study of dopamine transporter receptor occupancy measured with C-11 altropane

OBJECTIVE

Pediatric studies of the long-acting formulation (spheroidal oral drug absorption system [SODAS]) of the isomer dexmethylphenidate have shown a dose-dependent efficacy through 12 hours. However, there are no studies of central nervous system (CNS) dopamine transporter occupancies.

METHOD

Eighteen healthy volunteers underwent positron emission tomography (PET) imaging with C-11 altropane before and after administration of oral doses of SODAS dexmethylphenidate. Each group of 6 subjects received 1 of 3 doses (20 mg, 30 mg, 40 mg) before PET imaging at 1, 8, 10, 12 (20 mg and 30 mg), or 1, 8, 10, and 14 (40 mg) hours after dosing. Transporter occupancy was calculated by standard methods. The study was conducted from January 2007 through December 2007.

RESULTS

For all doses, plasma dexmethylphenidate levels and CNS dopamine transporter occupancies were greatest at 8 hours and decreased over time at 10, 12, and 14 hours. Plasma dexmethylphenidate levels were correlated to dose (P < .003). Mean plasma levels were ≥ 6 ng/mL to at least 8 hours with 20 mg (5.7 ng/mL), 10 hours with 30 mg, and 12 hours (extrapolated) with 40 mg. Dopamine transporter occupancies in the right caudate were 47% at 8 hours with 20 mg, 42% at hour 10 with 30 mg, and 46% (extrapolated) at hour 12 with 40 mg. Dopamine transporter occupancy was significantly correlated with plasma concentration of dexmethylphenidate (P < .001).

CONCLUSIONS

These results confirm the study hypothesis that central dopamine transporter occupancy parallels peripheral pharmacokinetic findings in orally administered long-acting dexmethylphenidate in later hours after administration.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00593138.

Dose response effects of lisdexamfetamine dimesylate treatment in adults with ADHD: an exploratory study

OBJECTIVE

To explore dose-response effects of lisdexamfetamine dimesylate (LDX) treatment for ADHD.

METHOD

This was a 4-week, randomized, double-blinded, placebo-controlled, parallel-group, forced-dose titration study in adult participants, aged 18 to 55 years, meeting Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.) criteria for ADHD.

RESULTS

Nearly all participants assigned to an LDX dose achieved their assigned dose with the exception of about 4% of participants assigned to the 50 mg or 14% assigned to the 70 mg doses. Higher doses of LDX led to greater improvements in ADHD-rating scale scores, independent of prior pharmacotherapy. This was evident for both inattentive and hyperactive-impulsive symptoms. The authors found some evidence for an interaction between LDX dose and baseline severity of ADHD symptoms.

CONCLUSION

For LDX doses between 30 and 70 mg/d, the dose-response efficacy effect for LDX is not affected by prior pharmacotherapy, but patients with a greater severity of illness may benefit more from higher doses, especially for hyperactive-impulsive symptoms. The results do not provide information about doses above 70 mg/d, which is the maximum approved dose of LDX and the highest dose studied in ADHD clinical trials.

Longitudinal course of deficient emotional self-regulation CBCL profile in youth with ADHD: prospective controlled study

BACKGROUND

While symptoms of deficient emotional self-regulation (DESR) have been long associated with attention-deficit/hyperactivity disorder (ADHD), there has been limited investigation of this aspect of the clinical picture of the disorder. The main aim of this study was to examine the predictive utility of DESR in moderating the course of ADHD children into adolescence.

METHODS

Subjects comprised 177 children with and 204 children without ADHD followed for an average of 4 years (aged 6-18 years at baseline, 54% male). Subjects were assessed with structured diagnostic interviews and measures of psychosocial functioning. DESR was defined by the presence (n = 79) or absence (n = 98) of Child Behavior Checklist (CBCL)-DESR profile (score ≥ 180 < 210 total of Attention, Aggression, and Anxious/Depressed subscales) at the baseline assessment.

RESULTS

Of subjects with DESR at baseline, 57% had DESR at follow-up. Persistent ADHD was significantly associated with DESR at follow-up (χ(2) ((1)) = 15.37, P < 0.001). At follow-up, ADHD + DESR subjects had significantly more comorbidities (z = 2.55, P = 0.01), a higher prevalence of oppositional defiant disorder (z = 3.01, P = 0.003), and more impaired CBCL social problems t-score (t((227)) = 2.41, P = 0.02) versus ADHD subjects.

CONCLUSION

This work suggests that a positive CBCL-DESR profile predicts subsequent psychopathology and functional impairments in children with ADHD suggesting that it has the potential to help identify children with ADHD at high risk for compromised outcomes.