The last two decades on preclinical and clinical research on inhalant effects.

This paper reviews the scientific evidence generated in the last two decades on the effects and mechanisms of action of most commonly misused inhalants. In the first section, we define what inhalants are, how they are used, and their prevalence worldwide. The second section presents specific characteristics that define the main groups of inhalants: (a) organic solvents; (b) aerosols, gases, and volatile anesthetics; and (c) alkyl nitrites. We include a table with the molecular formula, structure, synonyms, uses, physicochemical properties and exposure limits of representative compounds within each group. The third and fourth sections review the direct acute and chronic effects of common inhalants on health and behavior with a summary of mechanisms of action, respectively. In the fifth section, we address inhalant intoxication signs and available treatment. The sixth section examines the health effects, intoxication, and treatment of nitrites. The seventh section reviews current intervention strategies. Finally, we propose a research agenda to promote the study of (a) solvents other than toluene; (b) inhalant mixtures; (c) effects in combination with other drugs of abuse; (d) age and (e) sex differences in inhalant effects; (f) the long-lasting behavioral effects of animals exposed in utero to inhalants; (g) abstinence signs and neurochemical changes after interrupting inhalant exposure; (h) brain networks involved in inhalant effects; and finally (i) strategies to promote recovery of inhalant users.

Prevalence of and Factors Contributing to Glue Sniffing in the South Asian Association for Regional Cooperation (SAARC) Region: A Scoping Review and Meta-analysis.

Background: Although glue sniffing has been linked with significant morbidity and mortality, it is still under-researched and poorly recognized issue globally. Objective: A scoping review was performed to identify the factors and outcomes related to glue sniffing in India, Pakistan, Nepal and Bangladesh. Methods: Ten databases; Medline via Ovid, Google scholar, EBSCOhost (CINAHL Plus), ProQuest Central, PsycInfo, IndMED, Ovid Embase, Scopus, PubMed, and Science Direct were searched from their inception to January 2019 for both qualitative and quantitative studies examining any aspect of glue-sniffing. Studies published only in English language were included. Prevalence of glue-sniffing in SAARC region was the primary outcome measure. Findings: Of 8951studies screened, 344 were assessed for eligibility and 31 studies were included. The majority of the studies were conducted in India (15) and Pakistan (11). Meta-analysis of proportion, using random effects model, for both primary and secondary outcomes found that the highest incidence of glue sniffing was 57% (0.57, CI 95% 0.49-0.66) in India. The overall incidence of tobacco and naswar (snuff) as was 83% (0.83, 95% CI 0.80-0.86). Conclusions: The prevalence of glue sniffing, especially among street children, is alarmingly high and presents a challenge for health and social services for countries in SAARC region. More research work is required to examine long term impact of glue sniffing on physical and mental health.

The effect of adolescent inhalant abuse on energy balance and growth.

The abuse of volatile solvents such as toluene is a significant public health concern, predominantly affecting adolescents. To date, inhalant abuse research has primarily focused on the central nervous system; however, inhalants also exert effects on other organ systems and processes, including metabolic function and energy balance. Adolescent inhalant abuse is characterized by a negative energy balance phenotype, with the peak period of abuse overlapping with the adolescent growth spurt. There are multiple components within the central and peripheral regulation of energy balance that may be affected by adolescent inhalant abuse, such as impaired metabolic signaling, decreased food intake, altered dietary preferences, disrupted glucose tolerance and insulin release, reduced adiposity and skeletal density, and adrenal hypertrophy. These effects may persist into abstinence and adulthood, and the long-term consequences of inhalant-induced metabolic dysfunction are currently unknown. The signs and symptoms resulting from chronic adolescent inhalant abuse may result in a propensity for the development of adult-onset metabolic disorders such as type 2 diabetes, however, further research investigating the long-term effects of inhalant abuse upon energy balance and metabolism are needed. This review addresses several aspects of the short- and long-term effects of inhalant abuse relating to energy and metabolic processes, including energy balance, intake and expenditure; dietary preferences and glycemic control; and the dysfunction of metabolic homeostasis through altered adipose tissue, bone, and hypothalamic-pituitary-adrenal axis function.

Treatment-resistant depression as risk factor for substance use disorders-a nation-wide register-based cohort study.

BACKGROUND AND AIMS: Treatment-resistant depression (TRD) is common among patients with major depressive disorder (MDD). MDD may increase the risk for developing substance use disorders (SUD). The aim of this study was to investigate the risk for developing SUD among patients with TRD compared with other depressed patients. DESIGN: Observational cohort study. SETTING: Nation-wide governmental health registers in Sweden. PARTICIPANTS: All patients aged 18-69 years with an MDD diagnosis in specialized health care who had received at least one antidepressant prescription during 2006-14 were identified. Patients with at least three treatment trials within a single depressive episode were classified with TRD. MEASUREMENTS: Patients with TRD were compared with the whole MDD cohort regarding risk for obtaining a SUD diagnosis or medication using survival analyses adjusted for socio-demographics and comorbidities. FINDINGS: Of 121 669 MDD patients, 13% were classified with TRD. Among the patients without any history of SUD, patients with TRD had a risk increase for any SUD both ≤ 1 and > 1 year after antidepressant initiation [> 1 year hazard ratio (HR) = 1.4; 95% confidence interval (CI) = 1.3-1.5]. Risks were elevated for the subcategories of opioid (HR = 1.9, 95% CI = 1.4-2.5) and sedative SUD (HR = 2.7, 95% CI = 2.2-3.2). Patients with a history of SUD had a risk increase for any SUD ≤ 1 year after start of treatment (HR = 1.2, 95% CI = 1.1-1.4), and both ≤ 1 year and > 1 year for sedative (> 1 year HR = 2.0, 95% CI = 1.3-3.0) and multiple substance SUD (HR = 1.9, 95% CI = 1.4-2.5). CONCLUSIONS: Patients with treatment-resistant depression may be at greater risk for substance use disorders compared with other patients with major depressive disorder. Patterns may differ for patients with and without a history of substance use disorders, and for different categories of substance use disorder.

The prevalence of substance use in child welfare and general population eighth graders in the United States.

Background: Early substance use is an established risk factor for substance abuse and dependence. Objective: The current study sought to examine whether child welfare-involved eighth graders have higher rates of early substance use than general population eighth graders. Data from the first National Survey of Child and Adolescent Well-Being (NSCAW) were analyzed to assess the prevalence of self-reported substance use, including alcohol, marijuana, and inhalant use in child welfare-involved eighth graders (N = 896). These figures were compared to general eighth grade student population estimates from the Monitoring the Future Study (N = 16,900) using 95% confidence intervals (CIs). Finally, regression analyses were conducted to examine demographic predictors (i.e., age, gender, race/ethnicity, and out-of-home placement) of substance use among child welfare eighth graders. Results: Results indicated comparable or lower incidence of substances among child welfare eighth graders relative to the general population, but higher past 30-day inhalant use among child welfare youth in out-of-home placement (17.1%, 95% CI: 6.0%, 40.2%) than the general population (4.2%, 95% CI: 3.7%, 4.7%). Out-of-home placement was associated with higher inhalant use (lifetime ß = .659, p = .034; 30-day ß = .763, p = .040) and alcohol use (lifetime ß = .415, p = .028). Conclusions/Importance: These findings imply the need for screening and prevention education about substance use in child welfare populations, particularly in regards to inhalant use.

Reducing inhalant use in Latino adolescents through synchronized parent-adolescent interventions.

This article presents the effects of a synchronized Latino youth/parent intervention on adolescent inhalant use. The analytic sample included only Latino adolescents (n = 487) between the ages of 12 and 14. Randomized at the school-level, the design included three possible conditions: (1) child and parent received the prevention interventions, (2) only the parent received the prevention intervention, (3) neither child or parent received the prevention interventions. Drawing from the eco-developmental perspective, the overall hypothesis was that youth randomly assigned to the condition with both interventions will report the strongest inhalant use prevention outcomes. Descriptive statistics and regression tests of significant group differences by treatment condition confirmed the overall hypothesis. Children receiving the youth intervention and whose parents received the synchronized parenting intervention reported the strongest desired inhalant prevention effects. The findings are interpreted from an eco-developmental perspective and implications for practice, policy, and future research are discussed.

Killing Brain Cells and Skin Cells Simultaneously with Inhalant Abuse: Pearls from the National Burn Repository.

Over 20 million Americans have abused inhalants at least once in their lifetime. It is widely known that "huffing" increases risk for liver disease, renal failure, hypoxia, respiratory failure, dysrhythmias, and cardiac arrest. However, it is lesser known that inhalants can also cause thermal or frostbite injury. This study is a review of 2003 to 2012 National Burn Repository (NBR) records with a query for "huff," "inhalant," and corresponding ICD-9 codes. The NBR represents the cumulative data of subjects presenting to regional burn centers throughout the nation. Twenty-eight cases of inhalant injury were found. Approximately one-third were due to frostbite secondary to cold liquids exiting aerosol cans. The remaining two-third were due to thermal injury when the flammable solvent ignited. Median burn size was 3% total BSA (TBSA). Eight patients suffered inhalation injuries and one patient died. Although the median burn size of these patients was relatively small, some had significant injuries requiring long hospital length of stay. Direct costs of healthcare and indirect costs of lost wages make inhalant injury a significant public health problem. Multidisciplinary governmental efforts should be focused on prevention, education, recognition, and early intervention when inhalant abuse is suspected.

Acute harms associated with inhalant misuse: Co-morbidities and trends relative to age and gender among ambulance attendees.

BACKGROUND: Inhalant misuse is the deliberate inhalation of products containing toluene to induce intoxication. Chronic harms associated with inhalant misuse are well described; including alcohol and other drug use, mental health disorders, and suicidal behaviours. However, the nature of the acute harms from inhalants and characteristics of people who experience those harms are not well understood. Therefore, this study aimed to identify the acute harms associated with inhalant misuse attendances, and to determine whether these differ by age or gender. METHODS: Ambulance attendance data (Victoria, Australia) from January 2012 to June 2017 were extracted from a database of coded ambulance records. 779 ambulance attendances involving inhalant misuse were identified. Attendance characteristics were categorised by age and gender. Co-morbidities of current mental health, self-harm and suicidal behaviour were assessed, plus the involvement of alcohol and other drugs. RESULTS: Overall, attendances related to the acute harms of inhalant misuse have decreased over time, although that trend has reversed from January 2015. Gender differentiated the acute harms associated with inhalant misuse. Males were older and presented with concurrent alcohol and other drug use. Females were younger and presented with concurrent suicidal ideation and self-injury. Attendances for under 15-year-olds are increasing; this age group was over-represented, predominantly female, with a strong association with self-injury. CONCLUSIONS: Ambulance presentations related to inhalant misuse were associated with acute and serious harms. This study highlights that the acute treatment needs of those misusing inhalants are complex and may need to be tailored to gender and age groups.

Adolescent inhalant use and psychosis risk - a prospective longitudinal study.

BACKGROUND: Cross-sectional studies have suggested inhalant use is associated with psychosis. This association was examined in a longitudinal study accounting for other substance use and potential confounders. METHODS: We used a prospective sample (N = 6542) from the Northern Finland Birth Cohort 1986. Self-report questionnaires on substance use and psychotic experiences were completed when the cohort members were 15-16 years old. Inhalant use was categorized into four groups (never, once, 2-4 times, 5 times or more). Subsequent psychosis diagnoses (ICD-10) until age 30 years were obtained from national registers. Cox regression analysis was used to examine the association between adolescent inhalant use and risk of psychosis. RESULTS: During the observation period 124 individuals were diagnosed with incident psychosis. Overall, there were 225 (3.4%) subjects with any inhalant use, 18 (8.0%) of whom were diagnosed with psychosis during the follow up. Of non-inhalant users (n = 6317) 106 (1.7%) were diagnosed with psychosis. Compared to non-users, those using inhalants had increased risk of incident psychosis with most frequent inhalant use associated with the greatest risk (unadjusted HR = 9.46; 3.86-23.20). After adjusting for baseline psychotic experiences, other substance use, comorbid mental disorder and parental substance abuse, the increased risk of psychosis persisted (HR = 3.06; 1.05-8.95). Furthermore, a dose-response effect between inhalant use and risk of psychosis was identified (OR = 2.34; 1.83-2.99). CONCLUSIONS: Inhalant use in adolescence was independently associated with incident psychosis. The adverse health outcomes associated with adolescent inhalant use provide compelling reasons for implementation of policies to reduce the use of volatile substances in adolescents.

Neuropsychiatric characterization of individuals with inhalant use disorder and polysubstance use according to latent profiles of executive functioning.

BACKGROUND: Inhalant use disorder (IUD) is associated with deficits in executive functions (EFs). We described latent profiles of EFs and distribution of neuropsychiatric disorders and patterns of severity of use across these profiles. METHODS: Individuals with IUD were recruited at community-based residential facilities for substance use treatment in Mexico City. Latent profile analysis was conducted with the following tasks: self-ordered pointing, Stroop, Iowa gambling, Wisconsin Card Sorting and Tower of Hanoi. RESULTS: Three latent profiles were extracted from n = 165: lowest performances of inhibition of response and processing speed; lowest performance of self-monitoring, intermediate performance of inhibition of response and relatively spared processing speed; and intermediate performance of processing speed and self-monitoring, and relatively spared inhibition of response. CONCLUSION: Between-group differences were observed mainly for antisocial personality disorder and lifetime suicidal. Findings remark the need for identifying distinct profiles of EFs within these populations to better understand the transdiagnostic heterogeneity of EFs.

Inhalant use in adolescents in northern Russia.

PURPOSE: To determine the prevalence of inhalant use in Russian adolescents and to investigate associated psychosocial problems from a gender perspective. METHODS: Data on inhalant use and comorbid psychopathology were collected by means of self-reports from 2892 (42.4% boys) sixth to tenth grade students in public schools in Arkhangelsk, Russia. Multivariate analysis of covariance was used to assess differences in the levels of internalizing and externalizing problems in boys and girls, who were non-users and users of inhalants. RESULTS: The prevalence of inhalant use was 6.1% among boys and 3.4% among girls. Compared with non-users, inhalant users scored significantly higher on internalizing and externalizing problems, functional impairment and lower on academic motivation, with psychopathology increasing with age. While there were no gender differences for internalizing problems, increased levels of externalizing problems in inhalant users were gender-specific (significantly higher in boys). CONCLUSIONS: Inhalant use is related to significantly higher levels of comorbid psychopathology in Russian adolescents. Comprehensive, evidence-based prevention and intervention policies are needed to address inhalant use and its harmful effects.

Prevalence of youth gambling and potential influence of substance use and other risk factors throughout 33 European countries: first results from the 2015 ESPAD study.

BACKGROUND AND AIMS: Although generally prohibited by national regulations, underage gambling has become popular in Europe, with relevant cross-country prevalence variability. This study aimed to estimate the prevalence of underage gambling in Europe stratified by type of game and on-/off-line mode and to examine the association with individual and family characteristics and substance use. DESIGN: Our study used data from the 2015 European School Survey Project on Alcohol and Other Drugs (ESPAD) cross-sectional study, a survey using self-administered anonymous questionnaires. SETTING: Thirty-three European countries. PARTICIPANTS: Sixteen-year-old-year-old students (n = 93 875; F = 50.8%). MEASUREMENTS: The primary outcome measure was prevalence of past-year gambling activity. Key predictors comprised individual behaviours, substance use and parenting (regulation, monitoring and caring). FINDINGS: A total of 22.6% of 16-year-old students in Europe gambled in the past year: 16.2% on-line, 18.5% off-line. High prevalence variability was observed throughout countries both for mode and types of game. With the exception of cannabis, substance use shows a higher association with gambling, particularly binge drinking [odds ratio (OR) = 1.46, 95% confidence interval (CI) = 1.39-1.53), life-time use of inhalants (OR = 1.57, 95% CI = 1.47-1.68) and other substances (OR = 1.78, 95% CI = 1.65-1.92)]. Among life habits, the following showed a positive association: truancy at school (OR = 1.26, 95% CI = 1.18-1.35), going out at night (OR = 1.32, 95% CI = 1.26-1.38), participating in sports (OR = 1.30, 95% CI = 1.24-1.37). A negative association was found with reading books for leisure (OR = 0.82%, 95% CI = 0.79-0.86), parents' monitoring of Saturday night activities (OR = 0.81, 95% CI = 0.77-0.86) and restrictions on money provided by parents as a gift (OR = 0.89, 95% CI = 0.84-0.94). CONCLUSIONS: Underage gambling in Europe appears to be associated positively with alcohol, tobacco and other substance use (but not cannabis), as well as with other individual behaviours such as truancy, going out at night and active participation in sports, and is associated negatively with reading for pleasure, parental monitoring of evening activities and parental restriction of money.

Nitrite Inhalant Use and HIV Infection Among Chinese Men Who Have Sex With Men in 2 Large Cities in China.

OBJECTIVE: This study aims to examine the role that nitrite inhalants play in HIV infection and risky sex behaviors among Chinese men who have sex with men (MSM). METHODS: The study consisted of a baseline and a follow-up survey conducted in Beijing and Nanning, China. The baseline study recruited participants through online advertisements and peer referral to complete a questionnaire interview, oral rapid HIV test, and blood HIV and syphilis tests. The follow-up included a questionnaire interview, and optional oral and/or blood HIV testing. Questionnaires collected information about sociodemographic and behavioral characteristics. Univariable and multivariable logistic regression analyses were performed to evaluate associations between characteristics and nitrite inhalant use. RESULTS: One-third (29.8%) of 510 participants at baseline reported nitrite inhalant use during male-male sex in the past 6 months. Nitrite inhalant use was associated with higher odds of HIV infection (odds ratio 2.0, 95% confidence interval 1.1-3.7). Factors associated with nitrite inhalant use were as follows: never married, currently living in Beijing, not willing to test for HIV with oral self-test kit, and seeking male sex partners via the internet. In follow-up, 270 of 317 responded MSM reported having male-male sex after baseline and 17% of them used nitrite inhalants during sex. CONCLUSIONS: MSM who use nitrite inhalants are more likely to engage in risky HIV behaviors and have higher HIV infection risk than those who do not. Identifying MSM who use nitrite inhalants for targeted HIV interventions, such as HIV testing, might make HIV-prevention efforts more efficient among this population.

Inhalant Use and Mental Health Problems in Russian Juvenile Delinquents.

BACKGROUND: Inhalant use by children and adolescents has been linked to an increased risk of multiple drug use, mental health problems and antisocial behavior. OBJECTIVES: The purpose of this study was to examine the association between the frequency of inhalant use and psychiatric diagnoses among incarcerated delinquent youths in Russia. METHODS: A total of 370 incarcerated delinquents from a juvenile correction center in Northern Russia were assessed by means of a semi-structured psychiatric interview and by self-reports. RESULTS: Compared to non-users (N = 266), inhalant users (N = 104) reported higher rates of PTSD, early onset conduct disorder, ADHD, alcohol abuse and dependence, as well as higher levels of antisocial behavior, impulsiveness and more psychopathic traits. Frequent inhalant users also reported the highest rates of co-occurring psychopathology. CONCLUSIONS: Our findings suggest that inhalant use in delinquents is frequent and may require additional clinical measures to address the issue of psychiatric comorbidity.

Inhalant Abuse and Dextromethorphan.

Inhalant abuse is the intentional inhalation of a volatile substance for the purpose of achieving an altered mental state. As an important, yet underrecognized form of substance abuse, inhalant abuse crosses all demographic, ethnic, and socioeconomic boundaries, causing significant morbidity and mortality in school-aged and older children. This review presents current perspectives on epidemiology, detection, and clinical challenges of inhalant abuse and offers advice regarding the medical and mental health providers' roles in the prevention and management of this substance abuse problem. Also discussed is the misuse of a specific "over-the-counter" dissociative, dextromethorphan.

Adolescent inhalant use prevention, assessment, and treatment: A literature synthesis.

Inhalant use refers to the use of substances such as gases, glues, and aerosols in order to achieve intoxication, while inhalant use disorder (IUD) encompasses both DSM-IV-TR criteria for inhalant abuse and dependence. Inhalant use among adolescents is an international public health concern considering the severe medical and cognitive consequences and biopsychosocial correlates. In this paper, we summarize the current state of the literature on inhalant use among adolescents focusing on social context, prevention, assessment, and treatment strategies. Psychoeducation, skills training, and environmental supply reduction are helpful strategies for preventing adolescent inhalant use, while parent and adolescent self-report as well as physician report of medical signs and symptoms can aid in assessment and diagnosis. Although research has only begun to explore the treatment of inhalant use, preliminary findings suggest that a multimodal approach involving individual counselling (i.e., CBT brief intervention), family therapy, and activity and engagement programs is the first-line treatment, with residential treatment programs indicated for more severe presentations. The limited nature of treatments developed specifically for inhalant use combined with high prevalence rates and potential for significant impairment within the adolescent population indicate the need for further research. Research should focus on understanding the social context of use, establishing the efficacy of current adolescent substance use treatments adapted for inhalant use, and exploring long-term outcomes.

Long-Term Prevalence and Demographic Trends in U.S. Adolescent Inhalant Use: Implications for Clinicians and Prevention Scientists.

BACKGROUND: Inhalant use by adolescents is cause for concern due to the early age of inhalant use initiation and the many short- and long-term health consequences that can occur concurrently with and subsequent to use. However, inhalant use research has been limited relative to the literature available on other drug use. OBJECTIVES: The present research examined long-term trends in inhalant use prevalence, demographic risk factors of inhalant use, and median grade level of first use. METHODS: Monitoring the Future data from 1991 to 2011, which includes information drawn from United States eighth, tenth, and twelfth graders, were examined. The total sample comprised more than one million participants. Results were examined descriptively with figures and quantitatively with mixed-effects regression models of the effect of time on use rates. RESULTS: Inhalant use prevalence rates generally declined over the selected period. Though rates of use by males and females decreased significantly, the proportion of females among lifetime users increased significantly. Whites, Hispanics, and members of uncategorized "other" ethnicities showed the highest prevalence rates. Although the proportion of Whites among lifetime users decreased significantly, the proportion of Hispanics and "other" ethnicities increased significantly. The median first use was between sixth and ninth grade. CONCLUSIONS/IMPORTANCE: Results suggest a need to tailor inhalant use treatment and prevention programs to the needs of specific demographic groups and to target interventions early to prevent youth inhalant use. Strengths, limitations, and directions for future research are discussed.

Epidemiology of DSM-5 Drug Use Disorder: Results From the National Epidemiologic Survey on Alcohol and Related Conditions-III.

IMPORTANCE: Current information on the prevalence and sociodemographic and clinical profiles of individuals in the general population with DSM-5 drug use disorder (DUD) is limited. Given the present societal and economic context in the United States and the new diagnostic system, up-to-date national information is needed from a single uniform data source. OBJECTIVE: To present nationally representative findings on the prevalence, correlates, psychiatric comorbidity, disability, and treatment of DSM-5 DUD diagnoses overall and by severity level. DESIGN, SETTING, AND PARTICIPANTS: In-person interviews were conducted with 36,309 adults in the 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions-III, a cross-sectional representative survey of the United States. The household response rate was 72%; person-level response rate, 84%; and overall response rate, 60.1%. Data were collected April 2012 through June 2013 and analyzed from February through March 2015. MAIN OUTCOMES AND MEASURES: Twelve-month and lifetime DUD, based on amphetamine, cannabis, club drug, cocaine, hallucinogen, heroin, nonheroin opioid, sedative/tranquilizer, and/or solvent/inhalant use disorders. RESULTS: Prevalences of 12-month and lifetime DUD were 3.9% and 9.9%, respectively. Drug use disorder was generally greater among men, white and Native American individuals, younger and previously or never married adults, those with lower education and income, and those residing in the West. Significant associations were found between 12-month and lifetime DUD and other substance use disorders. Significant associations were also found between any 12-month DUD and major depressive disorder (odds ratio [OR], 1.3; 95% CI, 1.09-1.64), dysthymia (OR, 1.5; 95% CI, 1.09-2.02), bipolar I (OR, 1.5; 95% CI, 1.06-2.05), posttraumatic stress disorder (OR, 1.6; 95% CI, 1.27-2.10), and antisocial (OR, 1.4; 95% CI, 1.11-1.75), borderline (OR, 1.8; 95% CI, 1.41-2.24), and schizotypal (OR, 1.5; 95% CI, 1.18-1.87) personality disorders. Similar associations were found for any lifetime DUD with the exception that lifetime DUD was also associated with generalized anxiety disorder (OR, 1.3; 95% CI, 1.06-1.49), panic disorder (OR, 1.3; 95% CI, 1.06-1.59), and social phobia (OR, 1.3; 95% CI, 1.09-1.64). Twelve-month DUD was associated with significant disability, increasing with DUD severity. Among respondents with 12-month and lifetime DUD, only 13.5% and 24.6% received treatment, respectively. CONCLUSIONS AND RELEVANCE: DSM-5 DUD is a common, highly comorbid, and disabling disorder that largely goes untreated in the United States. These findings indicate the need for additional studies to understand the broad relationships in more detail; estimate present-day economic costs of DUDs; investigate hypotheses regarding etiology, chronicity, and treatment use; and provide information to policy makers about allocation of resources for service delivery and research. Findings also indicate an urgent need to destigmatize DUD and educate the public, clinicians, and policy makers about its treatment to encourage affected individuals to obtain help.

Patterns of concurrent substance use among adolescent nonmedical ADHD stimulant users.

OBJECTIVES: There are growing concerns about nonmedical use of ADHD stimulants among adolescents; yet, little is known whether there exist heterogeneous subgroups among adolescents with nonmedical ADHD stimulant use according to their concurrent substance use. METHODS: We used latent class analysis (LCA) to examine patterns of past-year problematic substance use (meeting any criteria for abuse or dependence) in a sample of 2203 adolescent participants from the National Surveys on Drug Use and Health 2006-2011 who reported past-year nonmedical use of ADHD stimulants. Multivariable latent regression was used to assess the association of socio-demographic characteristics, mental health and behavioral problems with the latent classes. RESULTS: The model fit indices favored a four-class model, including a large class with frequent concurrent use of alcohol and marijuana (Alcohol/marijuana class; 41.2%), a second large class with infrequent use of other substances (Low substance class, 36.3%), a third class characterized by more frequent misuse of prescription drugs as well as other substances (Prescription drug+class; 14.8%), and finally a class characterized by problematic use of multiple substances (Multiple substance class; 7.7%). Compared with individuals in Low substance class, those in the other three classes were all more likely to report mental health problems, deviant behaviors and substance abuse service use. CONCLUSIONS: Adolescent nonmedical ADHD stimulants users are a heterogeneous group with distinct classes with regard to concurrent substance use, mental health and behavioral problems. The findings have implications for planning of tailored prevention and treatment programs to curb stimulant use for this age group.