Trends and Disparities in Treatment for Co-occurring Major Depression and Substance Use Disorders Among US Adolescents From 2011 to 2019

IMPORTANCE Major depression and substance use disorders (SUD) commonly co-occur among adolescents, yet little is known about treatment use among adolescents with both conditions. Given the reciprocal influence of these conditions on each other and low prevalence of treatment overall, current information on quantification and trends in treatment of co-occurring depression and SUD is criticaltowardassessinghowthefieldisperforminginreachingyouthinneedoftheseservices,and among youth with sociodemographic risk factors. OBJECTIVE To examine temporal trends and sociodemographic disparities in the treatment of co-occurring major depression and SUD among US adolescents. DESIGN, SETTING, AND PARTICIPANTS This survey study used publicly available data for adolescents aged 12 to 17 years from the annual cross-sectional surveys of the National Survey on Drug Use and Health from 2011 to 2019 to assess co-occurrence of major depressive episodes (MDE) andSUDthroughtimeandprevalenceoftreatmentforeitherorbothoftheseconditions.Datawere analyzed between October 2020 and February 2021.


Introduction
Major depression and substance use disorder (SUD) both first emerge most commonly during adolescence [1][2][3] and are each associated with severe health and social consequences in late adolescence (eg, self-injuries, academic failure, violence, suicide) and adulthood (eg, sexual abuse, homelessness, unemployment, crime). 4,5Compared with adolescents with either depression or SUD alone, adolescents with both conditions are at higher risk for these negative consequences.
Emerging research has documented an upward trend in adolescent depression and, in contrast, an overall downward trend in SUD in recent years, [6][7][8] yet little is known about the trend of their co-occurrence in national samples.Given the severe consequences of depression and SUD, routine monitoring of their co-occurrence is critical to inform prevention and intervention. 9,10eoretically, adolescents with co-occurring depression and SUD should receive treatment for both conditions. 9,11Research indicates that treating depression alone does not significantly reduce SUD, 12,13 and SUD treatment alone does not result in remission of depression. 12Unfortunately, we lack comprehensive knowledge about trends and patterns in adolescents' unmet treatment needs for co-occurring conditions.Furthermore, prior findings have identified disparities in adolescent depression and SUD based on certain demographic, family, and social characteristics (eg, gender, race, family structure, residential stability). 14Yet, relatively little is known about potential corresponding disparities in unmet treatment need for co-occurring conditions.This information has direct implications for improving implementation of evidence-based practices, coordinating service delivery, and expanding treatment access for underserved adolescents.
The purpose of this study was to address these research gaps using nationally representative data for adolescents ages 12 to 17 years from National Survey on Drug Use and Health (NSDUH).
Specifically, this study aimed to examine temporal trends in the prevalence and treatment of co-occurring adolescent depression and SUD and identify disparities in unmet treatment needs among adolescents with both conditions.

Methods
This survey study was approved by the institutional review board at RTI International.Verbal informed consent was obtained from a parent or guardian, and verbal assent was obtained from each adolescent participant before survey administration.This study followed the American Association for Public Opinion Research (AAPOR) reporting guideline for survey studies.

Sample
The NSDUH is an annual cross-sectional survey sponsored by the Substance Abuse and Mental Health Services Administration within the US Department of Health and Human Services. 15Using a stratified multistage area probability sampling method, the NSDUH provides nationally representative data for the civilian, noninstitutionalized population aged 12 years or older from all 50 states and the District of Columbia. 15For this study, publicly available data for adolescents aged 12

Measures Major Depression
Major depression in the NSDUH was measured using a structured interview based on the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) (DSM-IV). 16Adolescents were classified as having a 12-month major depressive episode (MDE) if they had experienced either depressed mood or loss of interest or pleasure in daily activities for 2 weeks or longer in the past 12 months, while also experiencing 4 or more other symptoms that reflect a change in functioning, such as problems with sleep, eating, energy, concentration, and self-worth. 17olescents with 12-month MDE were further asked questions from the Sheehan Disability Scale to measure the level of MDE-related functional impairment in 4 major life activities or role domains (ie, chores at home, school or work, close relationships with family, and social life).On a 0 to 10 visual analog scale with categories of no interference (0), mild (1-3), moderate (4-6), severe (7-9), and very severe (10), ratings of 7 or greater were considered severe impairment.For this study, we dichotomized participants as having MDE-related severe functioning impairment or not. 17

Substance Use Disorders
In the NSDUH survey, adolescents were asked about their use of alcohol and illicit drugs (including marijuana, hallucinogens, inhalants, cocaine, or heroin, or nonmedical use of psychotherapeutics, such as tranquilizers, pain relievers, sedatives, or stimulants) in the past year.If respondents reported using a substance in the past year and on more than 5 days for alcohol and marijuana, they were further asked questions that correspond to the DSM-IV criteria for dependence or abuse (eg, tolerance, withdrawal, taking larger amounts or taking them for longer periods, inability to cut down, time spent using the substance, giving up activities, and continued use despite problems) in the past year. 16Adolescents were categorized as having 12-month SUD if they met DSM-IV criteria for an alcohol or illicit drug dependence or abuse.

Treatment
To assess treatment for depression overall, adolescents with 12-month MDE were asked if they had seen or talked to a physician or other professional about their MDE symptoms.

Statistical Analysis
Bivariate logistic regression analyses were first conducted to assess trends in the prevalence and treatment of co-occurring MDE and SUD overall and by sources of service, with survey year as the continuous independent variable.Following that, a series of multivariate logistic regression models were used to identify sociodemographic differences in the prevalence and treatment of co-occurring MDE and SUD.To adjust for potential time influence, the survey year variable was included in all multivariate models.Adolescents' MDE-related severe impairment was further added in the multivariate models for treatment to adjust for the potential influence of symptom severity; adjusted odds ratios (AORs) are reported.All analyses were performed using R statistical software version 4.0.3(R Project for Statistical Computing), accounting for the complex survey design, nonresponse bias, and noncoverage bias by using sampling weights provided by the NSDUH.In the NSDUH surveys from 2011 to 2019, the weighted response rates for adolescents ranged from 70.5% to 85.0%. 15Missing data ranged from 0% to 2.7% for the variables included in this study.Given that missing data were minimal, 20 we excluded participants with missing values, as recommended by the NSDUH. 15P values were 2-sided, and statistical significance was set at P = .05.Data were analyzed between October 2020 and February 2021.

Results
In

JAMA Network Open | Psychiatry
Treatment for Co-occurring Major Depression and Substance Use Disorders Among US Adolescents adolescents had both conditions.Lastly, an overall higher prevalence of co-occurring conditions was found in adolescents who moved in the last year (Table 3).

Disparities in the Treatment of Co-occurring MDE and SUD
As listed in

Discussion
This survey study found that from 2011 to 2019, the annual prevalence of co-occurring MDE and SUD remained largely stable, at between 1.4% to 1.7%, among US adolescents.Each year, less than 12% of adolescents with co-occurring MDE and SUD received treatment for both conditions, without a significant linear trend over time.In the past decade, multiple policies have been implemented to expand mental health and substance use treatment for adolescents, including the Mental Health Parity and Addiction Equity Act 21 and the Patient Protection and Affordable Care Act (ACA).practicing child and adolescent psychiatrists nationwide, with more than 15 million children and adolescents in need of specialty services. 23,24In 2018, 75% of counties in the US had no child psychiatrist, and 20% of medical schools did not sponsor child and adolescent psychiatry residency programs. 25To meet adolescents' treatment needs for MDE and SUD, more funding and policy support are needed to address such workforce shortages and deficiencies in treatment infrastructure.
Overall, adolescents with both conditions received treatment for MDE at much higher levels than for SUD, and a significant decrease in SUD treatment use was observed over time, particularly in outpatient rehabilitation facilities and self-help groups.7][28] To improve adolescent treatment use for SUD, enhanced service coordination between health care systems is essential.To ensure adolescents receive adequate treatment for SUD, more adolescent-specific programs that recognize the unique developmental characteristics and emotional needs of adolescents are needed.The difference in the prevalence of MDE and SUD treatment may also be explained by the greater stigma associated with SUD than MDE. 31 More community and school outreach programs are necessary to improve treatment motivation for SUD in adolescents.
Disaggregated analysis of treatment use by sources of service indicates that most adolescents with co-occurring conditions received specialty services from therapists, mental health clinics, and counselors for their MDE.In comparison, a smaller proportion of adolescents received SUD treatment in mental health clinics, suggesting that either adolescents were underdiagnosed for their SUD, or they were receiving segregated rather than integrated care for their co-occurring conditions.
Compared with separate treatment for each condition, integrated care has superior quality, effectiveness, and efficiency in treating co-occurring mental health and substance use problems. 32,33 optimize treatment outcomes for adolescents, enhanced efforts are needed to increase the provision of integrated care in clinical settings.
Another strategy would be to incorporate MDE and SUD services into primary care, which could reach far more adolescents through routine checkups. 34In recent years, many efforts have been made to improve mental health and substance use management in pediatric settings, including the guidelines for adolescent depression in primary care, 35 the Screening, Brief Intervention, and Referral to Treatment (SBIRT) for SUD, 36 and the patient-centered medical home model under the ACA. 37vertheless, this survey study found no significant change in adolescent treatment use for MDE or SUD from family physicians or pediatricians over time.A recent survey with pediatricians nationwide found that only 26% of pediatricians used validated screening instruments for substance use in clinical practice, 11% implemented the full SBIRT model, and 68% made referrals to substance use specialty care in response to a positive screen. 38To enhance implementation of evidence-based interventions, such as SBIRT, in pediatric settings, barriers perceived by pediatricians, including confidentiality issues, insufficient time during appointments, lack of expertise for managing substance use, and limited access to referral services, need to be addressed. 38is study also found extensive disparities in adolescent unmet treatment needs for co-occurring MDE and SUD.For example, while a higher level of treatment use were observed in girls than in boys for MDE, no gender difference was found in treatment use for SUD or co-occurring conditions.Such underutilization of MDE treatment in boys and insufficient service use for SUD in girls may be explained by gender stereotypes regarding proneness to emotional problems in girls and substance use problems in boys, which may create barriers to accurate identification and treatment of both disorders. 39,405 To improve treatment use for depression and SUD among racial and ethnic minority adolescents, more culturally and accessible interventions are crucial.
Moreover, we found that having private insurance was associated with treatment use for MDE, but not for SUD or co-occurring conditions.This finding is largely consistent with previous research identifying positive associations of insurance coverage with adolescent mental health treatment, [46][47][48] but not with SUD treatment. 49,50Mental health and SUD treatment have been designated as essential health benefits under the ACA. 51With further implementation of ACA and increased awareness of the policy, it is anticipated that more adolescents with co-occurring MDE and SUD who are covered by Medicaid will receive the treatment they need.
Lastly, although findings from this study identified higher odds of co-occurring MDE and SUD and unmet treatment needs among adolescents in single-parent households and those whose families who moved households frequently, further research is needed to clarify potential associations among socioeconomic status, family structure, and residential instability.As single parenthood and residential instability are largely markers associated with underlying social, educational, and familial disadvantages, 18,19 mental health and SUD interventions should target more on providing social support for single-parent households and improving family functioning.

Limitations
This study has several limitations.First, the NSDUH was administered in English and Spanish only, which overlooked immigrant families of other racial and ethnic groups with limited English proficiency.Second, the NSDUH survey excludes people (including adolescents) experiencing homelessness who do not use shelters and residents of hospitals and institutional group quarters (eg, juvenile centers); these individuals may have higher treatment needs for MDE and SUD.Third, the small sample sizes of adolescents with co-occurring MDE and SUD in each year and by specific sociodemographic characteristics may not have the statistical power to detect any small difference, possibly resulting in type II errors. 52Fourth, the small sample sizes of adolescents who used treatment in specific settings restricted our capability to conduct any setting-specific examination.
Future studies with larger sample sizes are needed to explore disparities and factors associated with adolescent MDE and SUD treatment use in specific settings.

Conclusions
This survey study found a stable trend in the prevalence and persistent gap in the treatment of co-occurring MDE and SUD among adolescents in the US from 2011 to 2019.Findings from this study point to ongoing deficiencies in the current service capacity for adolescent mental health and SUD treatment, highlight the need for improved coordination between service delivery systems, and call for enhanced policy and funding support for adolescents with unmet treatment needs.

Figure .
Figure.Patterns and Trends in Treatment Use Among Adolescents With Co-occurring Major Depressive Episode (MDE) and Substance Use Disorder (SUD) in the Past 12 Months in the National Survey on Drug Use and Health Treatment for Co-occurring Major Depression and Substance Use Disorders Among US Adolescents JAMA Network Open.2021;4(10):e2130280. doi:10.1001/jamanetworkopen.2021.30280(Reprinted) October 20, 2021 2/14 Downloaded From: https://jamanetwork.com/ on 09/29/2023 to 17 years in 2011 to 2019 were analyzed.The survey is administered in English and Spanish, and interviews are conducted using computer-assisted interviewing.

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To assess treatment for SUD overall, adolescents were asked if they had used treatment or counseling designed to help reduce or stop alcohol or drug use at any location in the past 12 months, including hospital (inpatient), rehabilitation facility (inpatient or outpatient), mental health center, emergency department, private physician's office, prison or jail, or self-help group, such as Alcoholics Anonymous or Narcotics Anonymous.Adolescents were considered as receiving treatment for MDE and SUD if they responded yes to both questions.All adolescents in the NSDUH were asked if they had received "any treatment or counseling for behavioral or emotional problems that were not caused by alcohol or drug use" from 11 sources of service, such as hospital (inpatient), day treatment program, mental health

Table 1
).While 37 968 adolescents (26.1%) did not have a father living in their household, 11 605 adolescents (8.3%) did not have a mother living in their household.Most adolescents (98 708 adolescents [74.5%]) had not moved households in the last 12 months.In total, 2072 adolescents (1.5%) had co-occurring MDE and SUD.

Table 2
lists the annual prevalence of treatment use for MDE and SUD from different sources of service among adolescents with both conditions.Overall, the most common sources of treatment use for MDE included private therapists, school mental health professionals, mental health clinics, and in-home counselors.From 2011 to 2019, a significant increase was observed in adolescent treatment use for MDE from private therapists (OR, 1.07; 95% CI, 1.02-1.12;P = .003)and mental health clinics (OR, 1.08; 95% CI, 1.03-1.14;P = .003).In contrast, the most common sources of treatment use for SUD were mental health clinics, self-help groups, hospitals, and outpatient rehabilitation facilities.Across the survey years, a significant decrease was noted in SUD treatment

Table 1 .
Sociodemographic Characteristics of All Adolescents in the National Survey on Drug Use and Health From 2011 to 2019 Treatment for Co-occurring Major Depression and Substance Use Disorders Among US Adolescents Abbreviation: CHIP, Children's Health Insurance Program. a Unweighted sample sizes and weighted percentages are reported.bIncludesindividuals identifying as more than 1 race or ethnicity or as none of the provided race and ethnicity options.JAMA Network Open | Psychiatry

Table 3 .
Multivariate Differences in the Prevalence of 12-Month Co-occurring MDE and SUD Among Adolescents in the National Survey on Drug Use and Health From 2011 to 2019 b P Յ .001.c P Յ .01. d Includes individuals identifying as more than 1 race or ethnicity or as none of the provided race and ethnicity options.e P Յ .05.

Table 4 .
Multivariate Differences in the Prevalence of Treatment Use in Adolescents With Co-occurring MDE and SUD in the National Survey on Drug Use and Health From 2011 to 2019

on 09/29/2023 not
Adolescents were asked if they had used treatment or counseling for illicit drug use or alcohol use at any location designed in the past 12 months.couldnot be computed for percentages owing to zero observed values.Includes individuals identifying as more than 1 race or ethnicity or as none of the provided race and ethnicity options.have adolescent-specific programs, and adolescents with SUD service needs are often integrated into programs that serve adults.
b c P Յ .05. d P Յ .001. e 95% CIs f P Յ .01. g Downloaded From: https://jamanetwork.com/ Taken together, these findings point to the need for gender-sensitive diagnosis and gender-responsive efforts to engage adolescents into treatment.Treatment for Co-occurring Major Depression and Substance Use Disorders Among US Adolescents use for MDE and both conditions.Previous research has identified multiple culturally unique barriers that may prevent racial and ethnic minority adolescents, such as Asian American, Native Hawaiian, and Pacific Islander adolescents, from seeking mental health treatment, including language barriers, cultural mistrust of health care practitioners, lack of social support, and limited provision of services in the community.
needed to integrate the community mental health workforce into the school system.Notably, lower prevalence of treatment use for co-occurring conditions was found in Hispanic adolescents than in White adolescents.Additionally, among all racial and ethnic groups, Asian American, Native Hawaiian, and Pacific Islander adolescents had the lowest prevalence of treatment JAMA Network Open | Psychiatry JAMA Network Open.2021;4(10):e2130280. doi:10.1001/jamanetworkopen.2021.30280(Reprinted) October 20, 2021 10/14 Downloaded From: https://jamanetwork.com/ on 09/29/2023