Substance Abuse Treatment, Prevention, and Policy volume 15, Article number: 43 (2020)
Young people with substance use problems face a high risk of co-occurring mental health problems, something that may involve a more difficult life situation, social problems as well as worse treatment outcomes. The aim of this study is to analyse self-reported mental health problems among young people receiving outpatient treatment for substance use problems in Sweden. We explore what types of mental health problems are more or less predominant, and whether there are significant differences between boys and girls. In addition, we analyse how various mental health problems covary with indicators of substance abuse severity.
The study is based on structured interviews with 1970 young people enrolled at outpatient clinics in 11 Swedish cities. The data was analysed through frequency- and averages-calculations, Chi-square tests and multivariate logistic regression analyses.
Self-reported mental health problems were common among the young people in the study. A relatively large percentage of the total group (34–54%) reported problems such as concentration difficulties, sleeping difficulties, anxiety and depression. At the same time, many of the young people did not report any symptoms and only a small group, about 20%, reported diagnosed mental health disorders. The results show substantial gender differences, with girls reporting significantly higher levels of mental health problems.
Multivariate logistic regression analyses demonstrated significant associations between severity of drug use problems and anxiety, concentration difficulties, aggression, hallucinations and mental stress caused by experiences of trauma.
Treatment needs are diverse within this group of young people who use drugs. Since girls report higher levels of all mental health problems, and a larger burden of psychosocial risk factors than boys, they are likely to require more comprehensive treatment interventions. The link between more severe drug problems and mental health problems points to the importance of exploring this relationship in treatment. A multidisciplinary approach, in which co-occurring problems can be addressed simultaneously, may be the best treatment form for many young people with drug problems.
The majority of young people with drug and alcohol problems suffer from concurrent mental health problems, referred to as co-occurring disorders or comorbidity [1,2,3,4]. Externalizing disorders such as Conduct Disorder (CD) and Attention Deficit Hyperactivity Disorder (ADHD) appear to be the most common mental health problems, but internalizing disorders such as depression, dysthymia and anxiety also commonly occur . Boys are usually over-represented with respect to externalizing disorders, while the opposite holds true for internalizing disorders [6, 7], even though some studies report equal gender distribution [1, 5].
Most studies show that young people with co-occurring problems have more extensive drug problems, higher levels of social problems and criminality, as well as worse treatment outcomes and greater risk of relapse, compared with young people with substance use problems alone [1,2,3,4, 8,9,10,11,12].
On the other hand, there are also studies demonstrating that a relatively large proportion of adolescents with substance use problems do not report any mental disorders or symptoms at initiation of treatment [10, 13, 14], and studies showing minor differences between young people with and without mental health problems with respect to treatment involvement, dropout rate and treatment outcome [15,16,17,18,19].
Few Swedish studies have addressed the association between drug use and mental health problems among young people. This despite a recent trend with an increased prevalence of mental health problems among young people, and a development with a growing number of young people being diagnosed with, and treated for drug use problems [20, 21].
The Swedish studies that have been conducted – mainly based on adolescents in inpatient or emergency care – show that the vast majority of young people have mental health problems prior to onset of drug use, and that as many as 90% demonstrate co-occurring disorders . There is little knowledge regarding mental health problems among broader groups of young people who use drugs in Sweden. There is also a lack of research on how different types of mental health problems may be linked to drug use severity among young people – this applies to Swedish research as well as to research on young people in general.
The aim of this article is to study self-reported occurrence of mental health problems among young people receiving outpatient treatment for substance use problems. We explore what types of mental health problems and social problems are more or less predominant, and whether there are significant differences in prevalence between boys and girls. In addition, we analyse how various mental health problems covary with indicators of substance abuse severity such as early onset of use, high frequency of use and poly drug use.
Occurrence of mental health problems among young people in substance abuse treatment
As stated earlier, co-occurring mental health problems are relatively common among young people with drug and alcohol problems, even though such occurrence may demonstrate large variations [23, 24]. For example, several research reviews state that 50% to 90% of young people with drug and alcohol problems also have extensive mental health problems [1,2,3, 5, 12, 23,24,25,26].
Studies involving inpatient subjects generally demonstrate higher prevalence of mental health problems compared with studies on young people treated in outpatient or community-based programmes [1, 5, 7, 11, 27, 28]. In one Swedish study on young people enrolled at an emergency care center, 90% of girls and 81% of boys met the criteria for at least one psychiatric disorder in addition to their substance use problems . Another Swedish study of young people receiving outpatient care for drug problems showed that 64% met the criteria for a psychiatric diagnosis . An Australian study with a broad selection of young people in different types of treatment for substance use problems found that only one third had co-occurring mental health problems .
A research review by Couwenbergh and colleagues  concluded that externalizing disorders such as CD and ADHD are the most frequently found co-occurring psychiatric disorders among young people with substance use problems, followed by internalizing disorders such as depression or dysthymia and anxiety. However, the rate of various disorders varies greatly between different studies: 24% to 82% for CD, 3% to 48% for depression/dysthymia, 1% to 38% for anxiety disorders, 3% to 38% for ADHD and 10% to 12% for post-traumatic stress disorder (PTSD).
Several studies suggests that it is common for young people with drug and alcohol problems to have multiple co-occurring psychiatric diagnoses when in treatment [9, 11, 18, 30], and that the occurrence of problems varies with age, co-occurring problems being more common among people in their late teens or early adulthood [19, 31].
In summary, prior research points to great variation in levels of co-occurring mental health problems among young people in treatment for drug and alcohol problems, as well as what types of mental disorders occur most frequently. The variation found in the different studies may have several explanations. These include differences in selection criteria, types of care, assessment methodology, diagnostic tools, diagnostic systems and timeframes during which the conditions occur (e.g., the past month, past year, any time in life), which collectively make comparisons between different studies and contexts difficult.
Associations between psychiatric disorders and severity of substance use problems
Only a few studies have investigated associations between various psychiatric disorders and indicators of severity of drug use problems among young people.
A study from Australia found that weakly or more frequent cannabis use in teenagers predicted an approximately twofold increase in risk for later depression and anxiety. In contrast, depression and anxiety in teenagers predicted neither later weekly nor daily cannabis use. Daily use in young women was associated with an over fivefold increase in the odds of reporting a state of depression and anxiety after adjustment for intercurrent use of other substances . Similarly, a study on undergraduate students in the US found frequent marijuana use to be associated with depression and other substance use and alcohol-related negative outcomes .
Early onset of cannabis use has been associated with higher rates of later substance use, juvenile offending, mental health problems, unemployment and school dropout .
Results from a longitudinal study from substance use treatment facilities in Norway showed a co-occurrence between poly-drug use and mental distress. Mental distress increased both in magnitude and over time with the number of drugs used. The authors conclude that use of multiple drugs and mental distress appears strongly co-related over time .
There are various theories about the causal relationship between mental health problems and drug problems. According to several researchers, psychiatric problems usually precede drug and alcohol problems [12, 36,37,38]. This can for instance be explained by the drugs serving as a self-medicating function by alleviating stress and other unpleasant emotions . However, the link between mental health problems and drug use cannot be explained solely on the basis of self-medication, since young people primarily state other reasons for using drugs [40,41,42]. The relationship between the two conditions can also be reversed, where drug and alcohol use increase the risk of mental health problems [32, 43, 44] . Another possible explanation is that underlying factors, such as difficult childhood circumstances or family problems may be the cause of both [4, 45, 46]. Mental health problems and substance abuse problems may also be intertwined and develop simultaneously over time. Finally, substance abuse and mental health problems may be mutually exclusive and coexist without any link [3, 32, 40]. It can be concluded that the association between drug and alcohol use problems and mental disorders is strong but extremely complex .
Materials and methods
Setting and sample
The study is based on structured interviews with young people receiving treatment for drug and alcohol problems. Data were gathered from specialized outpatient clinics for young people (13–21 years of age) with substance use problems in 11 Swedish cities. The participating cities are part of a researcher-practitioner collaboration network focusing on knowledge development in outpatient treatment for the present target group. The participating clinics represent Sweden’s three largest cities and eight additional cities around the country. The basic characteristics of the current sample are consistent with previous Swedish studies on the target group in outpatient treatment . The centers, usually referred to as Maria clinics, are carried out as a collaboration between the social services and the healthcare system. All of the clinics offer various types of treatment for substance use problems, as well as counselling and support for young people and their families. Average length of care is 4–6 months. Services offered by all clinics include psychosocial and medical assessment with a focus on substance use problems, drug testing, individual or family counselling, and manual-based treatment programmers. Personnel include social workers, nurses, psychologists and doctors .
Between 2014 and 2016, 2099 young people begun outpatient treatment for substance abuse problems at the participating Maria clinics. All young people initiating treatment are asked to participate in an enrolment interview that is used for both treatment and research purposes. Of the total group, 129 individuals were excluded in the study because they did not want to participate or because the information gathered was incomplete. The study is based on a total of 1970 young people, of whom 27% were girls and 73% boys. The average age was 17.6 years for both boys and girls. 28% of the young people were either born outside of Sweden or have two parents born outside Sweden. This means that the sample, in this respect, is representative for young people in Sweden’s larger cities.
Instruments and materials
UngDOK is a structured interview that was developed specifically for young people with various types of drug and alcohol problems. The primary purpose of the interview is to identify the problems, needs and current social situation of young people in order to arrive at the appropriate assessment, plan and implementation of treatment. The information gathered can also serve as a basis for follow-up and evaluation of the interventions and outcomes of the various local clinics. In a reliability and validation study, the quality of the UngDOK interview method was found to be satisfactory .
The interviews were conducted by the therapists at the time of admission. It contains a total of 75 questions covering the following ten aspects of life: housing and financial support, occupation, treatment history, criminality, childhood environment, exposure to violence, family and relationships, physical health, mental health, as well as alcohol and drug use.
The analyzed variables describe individual characteristics regarding: social situation, drug and alcohol use, and mental health. The study only uses anonymized data, and permission for storage and processing of data for research purposes has been obtained from the research ethics committee at the National Board of Health and Welfare.
Variables and statistical analysis
Initially, the study group was categorized by gender and the variables included in the study regarding mental health problems were analysed for gender differences. The data was processed and analysed by SPSS Statistics 24 software and Chi2 and t-tests were used for analysing levels of significance. To investigate the relationship between various mental health problems and drug use, multivariate logistic regression analysis with three models was carried out. As dependent variables, we used the following dichotomized variables that indicate severity of drug use: high frequency of use, i.e. two–three days a week or more for the primary drug (model 1), early onset of substance use, i.e. age 12 or younger for alcohol intoxication and age 13 or younger for drugs use (model 2), and presence of poly drug use, i.e. regular use of two or more drugs during the last three months (model 3). The independent variables in all three analysis models include age and gender, as well as self-reported mental health problems over the past 30 days: depression, anxiety, concentration difficulties, aggressive behaviour, suicidal thoughts, hallucinations, eating disorders, self-harming behaviour, and psychological stress from traumatic events (e.g. witnessed or being subjected to violence or sexual abuse). The results of these analyses are reported using odds ratios and significance levels. The explained variance for each model is presented using Cox & Snell and Nagelkerke.
Table 1 shows the childhood environment and social situation of the young people, as well as their self-reported drug and alcohol use at treatment initiation.
Richert, T., Anderberg, M. & Dahlberg, M. Mental health problems among young people in substance abuse treatment in Sweden. Subst Abuse Treat Prev Policy 15, 43 (2020). https://doi.org/10.1186/s13011-020-00282-6