Prevalence of attention-deficit hyperactivity disorder in substance use disorder patients: A meta-analysis and meta-regression analysis

Poster Abstracts from the AAAP 20th Annual Meeting and Symposium

Previous studies have identified significant variability in attention-deficit / hyperactivity disorder (ADHD) prevalence estimates worldwide, largely explained by methodological procedures. However, increasing rates of ADHD diagnosis and treatment throughout the past few decades have fuelled concerns about whether the true prevalence of the disorder has increased over time. We updated the two most comprehensive systematic reviews on ADHD prevalence available in the literature. Meta-regression analyses were conducted to test the effect of year of study in the context of both methodological variables that determined variability in ADHD prevalence (diagnostic criteria, impairment criterion and source of information), and the geographical location of studies. We identified 154 original studies and included 135 in the multivariate analysis. Methodological procedures investigated were significantly associated with heterogeneity of studies. Geographical location and year of study were not associated with variability in ADHD prevalence estimates. Confirming previous findings, variability in ADHD prevalence estimates is mostly explained by methodological characteristics of the studies. In the past three decades, there has been no evidence to suggest an increase in the number of children in the community who meet criteria for ADHD when standardized diagnostic procedures are followed.

A robust and bidirectional comorbidity between attention deficit hyperactivity disorder (ADHD) and psychoactive substance use disorder (alcohol or drug abuse or dependence) has been consistently reported in the extant literature. First-degree relatives from a large group of pediatrically and psychiatrically referred boys with (112 probands, 385 relatives) and without (105 probands, 358 relatives) ADHD were comprehensively assessed by blind raters with structured diagnostic interviews. Familial risk analysis examined the risks in first-degree relatives for ADHD, psychoactive substance use disorder, alcohol dependence, and drug dependence after stratifying probands by the presence and absence of these disorders. ADHD in the proband was consistently associated with a significant risk for ADHD in relatives. Drug dependence in probands increased the risk for drug dependence in relatives irrespective of ADHD status, whereas alcohol dependence in relatives was predicted only by ADHD probands with comorbid alcohol dependence. In addition, ADHD in the proband predicted drug dependence in relatives, and drug dependence in comparison probands increased the risk for ADHD in relatives. Both alcohol dependence and drug dependence bred true in families without evidence for a common risk between these disorders. Patterns of familial risk analysis suggest that the association between ADHD and drug dependence is most consistent with the hypothesis of variable expressivity of a common risk between these disorders, whereas the association between ADHD and alcohol dependence is most consistent with the hypothesis of independent transmission of these disorders. Findings also suggest specificity for the transmission of alcohol and drug dependence.

BackgroundADHD is a common and disabling disorder, with an increased risk for coexisting disorders, substance abuse and delinquency. In the present study, we aimed at exploring ADHD and criminality. We estimated the prevalence of ADHD among longer-term prison inmates, described symptoms and cognitive functioning, and compared findings with ADHD among psychiatric outpatients and healthy controls.MethodsAt Norrtälje Prison, we approached 315 male inmates for screening of childhood ADHD by the Wender Utah Rating Scale (WURS-25) and for present ADHD by the Adult ADHD Self-Report Screener (ASRS-Screener). The response rate was 62%. Further, we assessed 34 inmates for ADHD and coexisting disorders. Finally, we compared findings with 20 adult males with ADHD, assessed at a psychiatric outpatient clinic and 18 healthy controls.ResultsThe estimated prevalence of adult ADHD among longer-term inmates was 40%. Only 2 out of 30 prison inmates confirmed with ADHD had received a diagnosis of ADHD during childhood, despite most needed health services and educational support. All subjects reported lifetime substance use disorder (SUD) where amphetamine was the most common drug. Mood and anxiety disorders were present among half of subjects; autism spectrum disorder (ASD) among one fourth and psychopathy among one tenth. Personality disorders were common; almost all inmates presented conduct disorder (CD) before antisocial personality disorder (APD). Prison inmates reported more ADHD symptoms during both childhood and adulthood, compared with ADHD psychiatric outpatients. Further, analysis of executive functions after controlling for IQ showed both ADHD groups performed poorer than controls on working memory tests. Besides, on a continuous performance test, the ADHD prison group displayed poorer results compared with both other groups.ConclusionsThis study suggested ADHD to be present among 40% of adult male longer-term prison inmates. Further, ADHD and coexisting disorders, such as SUD, ASD, personality disorders, mood- and anxiety disorders, severely affected prison inmates with ADHD. Besides, inmates showed poorer executive functions also when controlling for estimated IQ compared with ADHD among psychiatric outpatients and controls. Our findings imply the need for considering these severities when designing treatment programmes for prison inmates with ADHD.

Variability in the prevalence of adult ADHD in treatment seeking substance use disorder patients: Results from an international multi-center study exploring DSM-IV and DSM-5 criteria

Epilepsy and attention-deficit hyperactivity disorder (ADHD) were reported to co-occur at rates higher than expected for coincidental findings. This study investigated the prevalence of both disorders in community-based primary care practice. The central database of the second-largest health maintenance organization in Israel was searched for all children aged 6 to 13 years (n = 284 419; 51.5% males) diagnosed as having ADHD according to the physicians' records and/or the filling of at least 10 prescriptions for antiepileptic medications according to pharmacy records. The prevalence of epilepsy in the total population was 5 out of 1000 children, and the prevalence of ADHD was 12.6%. More than one-fourth (27.7%) of the epileptic children were also diagnosed as having ADHD. On multivariate analysis, children with ADHD had almost twice the risk of epilepsy than children without ADHD. This study supports hospital-based findings of a strong interrelationship between ADHD and epilepsy. The high rate of ADHD in Israeli children warrants further investigation.

Prevalence estimates of the attention-deficit hyperactivity disorder (ADHD) and the rate of persistence of symptoms across the lifespan are heterogeneous, raising questions about the validity of the diagnosis. This review aims to discuss potential reasons for variability in ADHD prevalence estimates and rates of symptom persistence, as well as to present ADHD prevalence rates during the lifespan. The best available estimates of ADHD prevalence are around 5.29% for children and adolescents and 4.4% in adulthood. Estimates of ADHD prevalence and rate of symptom persistence over time seem to be highly affected by methodological characteristics of the studies. The review of ADHD epidemiology highlights the need for standardizing study methodologies to make findings comparable. Even so, epidemiological cross-national data seem to support the validity of ADHD.

(1) Background: Attention deficit hyperactivity disorder (ADHD) is a common comorbid condition in opioid use disorder (OUD) and is associated with a more severe course of substance use. Patients with severe OUD who have not responded to oral opioid maintenance treatment can be treated with intravenous diamorphine up to three times per day. Here, we investigated the prevalence of ADHD among patients undergoing either daily diamorphine maintenance treatment or daily oral opioid maintenance treatment. (2) Methods: We assessed all participants with the WURS-k and the ADHD-SR. The Diagnostic Interview for ADHD in Adults (DIVA) was performed with all participants who met the cut-off in the WURS-k and/or ADHD-SR. (3) Results: The overall prevalence of ADHD was 17.9%. Prevalence of ADHD among patients undergoing daily diamorphine maintenance treatment was 14.3%. Prevalence of ADHD among patients undergoing daily oral opioid maintenance treatment was 20.3%. The combined presentation of ADHD was the most prevalent condition. In urine samples of participants with comorbid ADHD, heroin was detected the most and cocaine the least frequently. (4) Conclusions: Almost one out of five patients with OUD suffered from comorbid ADHD. In 83.3%, ADHD had not been diagnosed prior to participation in this study. Thus, patients with SUD could benefit from being routinely screened for ADHD.

Dear Editor, Attention deficit hyperactivity disorder (ADHD), is a common, highly heritable childhood-onset psychiatric disorder affecting 2% – 6% of children worldwide. The recent paper examines the effects of child and adult ADHD symptoms in adults among male students on adult addiction acknowledgment and alcoholism potential (1). This article is an original study which provides that adult ADHD and child ADHD predict addiction acknowledgment while child ADHD and impulsivity predict alcohol potential. These findings add new evidence about prediction of adolescent and adult drug abuse and use by early ADHD. However, the biological mechanism of the relationship between ADHD and substance problems is still unclear. One of the important mechanisms is genetic correlation due to shared genetic loci. First, it has been shown that both ADHD and alcohol dependence have strong genetics components. Twin and adoption studies have indicated that ADHD has high heritability in the range of 75% – 91% (2), while family, twin, and adoption studies have revealed that genetic and environmental factors and their interactions contribute to the development of alcohol dependence, with a heritability of more than 50% (3). Second, ADHD has been found to be highly comorbid with nicotine dependence and alcohol dependence. Segregation analysis has provided multigenerational evidence of cosegregation among ADHD, nicotine dependence, and alcohol dependence, while linkage analysis has suggested several regions on human chromosomes with pleiotropic effects on ADHD and alcohol dependence (4). For example, significant linkages at 4q13.1 - 13.2 and 5q31 - 33 for ADHD has been implicated in alcohol dependence and nicotine dependence (4). Third, genetic association studies have suggested several genes which are responsible for both ADHD and alcohol dependence. For example, it has been reported associations between the dopamine transporter (DAT) gene polymorphisms and human disorders including ADHD and alcohol dependence (5). The variants of the dopamine D2 receptor gene (DRD2) has been found to be associated with alcoholism, drug dependency, obesity, smoking, pathological gambling, ADHD, Tourette syndrome, as well as other related compulsive behaviors (6). The tachykinin receptor 1 (TACR1) gene has been reported to be associated with bipolar disorder and alcoholism as well as ADHD (2). However, parts of the associations are not strong and the results are not always consistent due to biologic mechanisms (genetic heterogeneity, gene-gene interactions and gene-environment interactions etc.) and spurious mechanisms (inadequacies of genomic markers, type 1 error, limited sample sizes and power, cohort and age effects, and bias etc.). In addition, some other genes, such as the nicotinic receptor CHRNA5-A3-B4 subunit genes, do not contribute to the common genetic predisposition of ADHD and alcohol dependence (2, 7). In short, the current results not only support previous studies about the relationship between ADHD and alcohol and drug dependence but also provide further evidence on prediction of future substance dependence in adulthood through early ADHD (1). However, the sample size for the current study is relative small; therefore the results need further investigation using large sample and confirmation in other populations. In addition, further genetic and epigenetic study to identify the disease-causing variants including gene-environment interactions in ADHD and alcohol dependence would have promise for understanding the pathogenesis of these comorbity psychiatric disorders, predicting the risks and developing potential treatments for ADHD and alcohol dependence.

Background: The International Collaboration on ADHD and Substance Abuse (ICASA) is a network of 28 centers from 16 countries initiated to investigate the link between attention deficit-hyperactivity disorder (ADHD) and substance use disorder (SUD). In this article, we present the mission, the results of finished studies, and the current and future research projects of ICASA. Methods: During the past 10 years, 3 cross-sectional studies were conducted: two International ADHD in Substance use disorders Prevalence (IASP-1 and IASP-2) studies, directed at the screening, diagnosis, and the prevalence of adult ADHD in treatment-seeking patients with SUD, and the Continuous performance test for ADHD in SUD Patients (CASP) study, testing a novel continuous performance test in SUD patients with and without adult ADHD. Recently, the prospective International Naturalistic Cohort Study of ADHD and Substance Use Disorders (INCAS) was initiated, directed at treatment provision and treatment outcome in SUD patients with adult ADHD. Results: The IASP studies have shown that approximately 1 in 6 adult treatment-seeking SUD patients also have ADHD. In addition, those SUD patients with adult ADHD compared to SUD patients without ADHD report more childhood trauma exposure, slower infant development, greater problems controlling their temperament, and lower educational attainment. Comorbid patients also reported more risk-taking behavior, and a higher rate of other psychiatric disorders compared to SUD patients without ADHD. Screening, diagnosis, and treatment of this patient group are possible even before abstinence has been achieved. The results of the CASP study are reported separately in this special issue. Conclusions: The ICASA research to date has demonstrated a high prevalence of comorbid ADHD and SUD, associated with elevated rates of additional comorbidities and risk factors for adverse outcomes. More research is needed to find the best way to treat these patients, which is the main topic of the ongoing INCAS study.

Although there has been extensive research in the area of Attention-deficit Hyperactivity Disorder (ADHD), the estimated prevalence of this disorder ranges from 1% to 20%. This variability is due in part to variations in how one defines ADHD and the difficulty of precisely measuring the features of the syndrome. Additionally, problems of differential diagnosis and comorbidity of ADHD with other disorders may impact resultant prevalence rates. The present study was conducted in order to examine the impact of various qualitative and quantitative differences in the diagnostic process on the prevalence of ADHD in samples of children in special education and children referred to a tertiary-care specialty clinic for learning disabilities (LD) and ADHD. Of particular interest was the prevalence of ADHD with no other psychopathology (“pure” ADHD) in the two samples. Children with pure ADHD made up only 15.8% of the special education sample (teacher rating only). In contrast, the prevalence of pure ADHD in the specialty clinic sample ranged from 35.6% (teacher rating only) to 11.9% (parent rating only). Only 5.9% were rated by both teacher and parent as pure ADHD. The clinical and methodological implications of these findings are discussed in terms of the criteria for diagnosis of ADHD and implications for future research.

Family, twin, and adoption studies show attention deficit hyperactivity disorder (ADHD) to have a substantial genetic component, and some studies have reported an association between ADHD and the dopamine D4 (DRD4) gene. The authors recruited 27 triads that comprised an ADHD adult, his or her spouse, and their ADHD child. These triads were assessed for ADHD, and their DNA was genotyped for DRD4 alleles. A multiallelic transmission disequilibrium test suggested an association between ADHD and the DRD4 7-repeat allele. Among family members, the number of 7-repeat alleles predicted the diagnosis of ADHD. Prior reports of an association between ADHD and DRD4 generalize to families recruited through clinically referred ADHD adults. However, because there are some conflicting studies, further work is needed to clarify the role of DRD4 in the etiology of the disorder.

1. Ximena Sanchez-Samper, MD* 2. John R. Knight, MD* 1. *Center for Adolescent Substance Abuse Research, Children's Hospital Boston, Boston, Mass After completing this article, readers should be able to: 1. Discuss current trends in adolescent substance use and the specific substances used most commonly among 8th, 10th, and 12th graders. 2. Identify risk and protective factors, including genetic and environmental correlates, for the initiation of substance use in adolescents. 3. Discuss the most common concomitant mental health disorders and how they can affect the course of diagnosis and treatment for substance abuse. 4. Delineate the variety of treatment options available. 5. Describe the role of the pediatrician in educating patients and families on substance abuse prevention; performing screening and initial assessments; and providing support, brief counseling, or referrals for in-depth treatment. Adolescence is a time of physical, emotional, and psychological maturation as well as a period of searching for independence and experimentation. One area of experimentation associated with adolescence is substance use. (1) Although many adolescents experiment with drugs and alcohol from time to time without enduring problems, those who develop the disorders of substance abuse and dependence make substance use a major public health concern. The Monitoring the Future Study (MTFS) is a nationwide survey measuring smoking, drinking, and illicit drug use among nearly 50,000 8th, 10th, and 12th graders in more than 400 secondary schools in the United States each year. (2)(3) According to the 2006 overview of findings from the MTFS, approximately one fifth (21%) of today's 8th graders, more than one third (36%) of 10th graders, and nearly half (48%) of all 12th graders reported using an illicit drug at least once during their lifetimes. Despite a minimum legal age requirement to purchase alcohol, 6% of 8th graders, 19% of the 10th graders, and 30% of the 12th graders self-reported drunkenness during the month prior to being interviewed. (2)(3) Among the problems experienced by adolescents who use alcohol and drugs are …

BackgroundAdolescents with attention-deficit/hyperactivity disorder (ADHD) are known to be at significantly greater risk for the development of substance use disorders (SUD) compared to peers. Impulsivity, which could lead to higher levels of drug use, is a known symptom of ADHD and likely accounts, in part, for this relationship. Other factors, such as a biologically increased susceptibility to substance dependence (addiction), may also play a role.ObjectiveThis report further examines the relationships between childhood ADHD, adolescent- onset SUD, and substance abuse and substance dependence in adulthood.MethodIndividuals with childhood ADHD and non-ADHD controls from the same population-based birth cohort were invited to participate in a prospective outcome study. Participants completed a structured neuropsychiatric interview with modules for SUD and a psychosocial questionnaire. Information on adolescent SUD was obtained retrospectively, in a previous study, from medical and school records. Associations were summarized using odds ratios (OR) and 95% CIs estimated from logistic regression models adjusted for age and gender.ResultsA total of 232 ADHD cases and 335 non-ADHD controls participated (mean age, 27.0 and 28.6 years, respectively). ADHD cases were more likely than controls to have a SUD diagnosed in adolescence and were more likely to have alcohol (adjusted OR 14.38, 95% CI 1.49–138.88) and drug (adjusted OR 3.48, 95% CI 1.38–8.79) dependence in adulthood. The subgroup of participating ADHD cases who did not have SUD during adolescence were no more likely than controls to develop new onset alcohol dependence as adults, although they were significantly more likely to develop new onset drug dependence.ConclusionsOur study found preliminary evidence that adults with childhood ADHD are more susceptible than peers to developing drug dependence, a disorder associated with neurological changes in the brain. The relationship between ADHD and alcohol dependence appears to be more complex.

P.2.017 - ADHD and related aspects in a standardised investigation in Austrian prisons – incarcerated patients with substance use disorders