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Substance Use Disorders Compared to Other Mental Disorders: An Update

A common dilemma encountered by clinicians, insurance providers, and legislators alike is determining whether substance abuse is a typical mental illness or a unique disorder of its own. Distinguishing whether substance use disorder is fundamentally different from other mental disorders influences decisions on how substance use disorders should be treated and ultimately, how the research and treatment of these disorders should be funded. The treatment of individuals with substance use disorders and co-occurring mental disorders has become a topic of great interest due to the large prevalence of co-occurring disorders. In a 2012 National Survey on Substance Abuse and Mental Health, of the 20.7 million adults with a substance use disorder within the past year, 40.7 percent had a co-occurring mental illness (SAMHSA, 2013). Furthermore, among the 43.7 million adults in 2012 with a mental illness, 19.2 percent met criteria for a substance use disorder (SAMHSA, 2013). Considering these statistics, it makes fiscal sense why some insurance companies only pay for substance abuse treatment if another mental disorder is present (Fisher & Harrison, 2012, pp. 138–9).


Beyond making fiscal sense, integrated treatment that simultaneously addresses an individual’s substance use and co-occurring mental illness has been associated with better treatment outcomes, such as decreased substance use and improved psychiatric symptoms and functioning (SAMHSA, 2009). Despite endorsements of various substance abuse and mental health organizations for holistic, integrative care, such treatment is not always practical, and is far from commonplace within the current health care system. Drake, O’Neal, and Wallbach (2008) found that individuals with co-occurring disorders were often treated for one disorder or the other, and tended to be passed back and forth between independent service systems with incompatible interventions. This brings up another matter of contention regarding whether individuals with substance use disorders should be treated alongside individuals with various other mental disorders.


Therefore, determining whether a substance use disorder is a typical mental illness is necessary to ensure competent treatment and care of such disorders. This article will examine how substance use disorders compare to other mental disorders in diagnostic characterization, prevalence, and treatment, with a special emphasis on best practices in treating substance use disorders as well as policy implications.


Mental Disorders  


Differentiating between substance use disorder and the typical mental illness is a matter of how we operationally define these concepts. In order for a concept to be scientifically investigated, it must be explicitly defined so that it can be measured. A reliable and valid definition ensures that researchers and clinicians are examining the same phenomenon. Because mental disorders tend to manifest themselves differently depending on the individual, their environment, and other extraneous factors, defining what a “typical” mental disorder is can be difficult. 


The American Psychiatric Association (APA) Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) defines a mental disorder as “a syndrome characterized by clinically significant disturbances in an individual’s cognition, emotion regulation, or behavior that reflects a dysfunction in the psychological, biological, or developmental processes underlying mental functioning” (2013). The most common mental disorders in the US are depressive disorders, anxiety disorders, trauma related disorders, and bipolar disorder (NIMH, 2012). Additionally, it is estimated that 9.1 percent of the population would meet the criteria for a personality disorder, placing personality disorders among the most common disorders (NIMH, 2012).


The Substance Abuse and Mental Health Services Association (SAMHSA) defines any mental disorder (AMI) as a diagnosable mental, behavioral, or emotional disorder, excluding developmental and substance use disorders (2013). SAMHSA differentiates AMI from severe mental illness (SMI), which it defines as “a diagnosable mental, behavioral, or emotional disorder (excluding developmental and substance use disorders) that has resulted in serious functional impairment, which substantially interferes with or limits one or more major life activities” (SAMHSA, 2013). An individual must be eighteen years or older to meet this criteria. In 2012, an estimated 18.6 percent of the US population had AMI. Of that 18.6 percent, 4.1 percent had SMI. Finally, of the 18.6 percent of the national population with AMI—43.7 million people—41 percent received treatment in 2012 (SAMHSA, 2013).


Substance Use Disorders  


According to the DSM-5, substance use disorder is indeed its own mental disorder diagnosis. Substance use disorders are broken down into ten substance classes. The essential features of a substance use disorder include cognitive, behavioral, and physiological symptoms that produce clinically significant impairment. Additional criteria that are applicable across classes of substances are tolerance; significant time spent obtaining, using, or recovering from substances; an intense desire to use, or cravings; risky use of the substance; and withdrawal upon the cessation of substance use. According to SAMHSA, 8.5 percent of the US population aged twelve and older was classified with substance use disorders in the year 2012 (2013). In 2012, only 1.5 percent of the population received treatment for their substance use disorders (SAMHSA, 2013).




In the US, substance use disorders are currently treated with a variety of approaches and modalities. On surface level, many of these treatment vehicles appear similar to how typical mental illnesses are treated. For example, both substance use disorders and other mental disorders are treated in various settings, by clinicians with differing theoretical orientations, and with a range of treatment modalities. Often times, substance abuse and other mental disorders are co-occurring, providing further support for treating individuals with these disorders together or in the same manner.


Despite treatment similarities and co-occurrence, substance use disorders have unique characteristics which contrast from the typical or most commonly occurring mental illnesses in a number of ways, influencing how they must be treated and managed. For some individuals struggling with their substance use, detoxification services are necessary before further therapeutic work is possible. The goal of detoxification programs is to address both the physical and mental or psychological aspects of substance use. According to one treatment manual published in 2009, detoxification programs are intended to 


provide a safe withdrawal from the substance of dependence and enable individuals to become alcohol- or drug-free[,] . . . provide withdrawal that protects people’s dignity…[and] prepare individuals for ongoing alcohol and drug abuse treatment (Office on Child Abuse and Neglect, 2009). 


Depending on the substance of abuse and severity of impairment involved, it may be appropriate for treatment to begin without cessation of substance use, taking an approach of motivating the client to make changes to his or her lifestyle. 


In terms of the societal treatment of individuals with substance use disorders, much stigma can impact the lives of these individuals, which can come from virtually any source—whether through friends, family, employers, or mental health professionals themselves. The labels “addict” or “alcoholic” are widely associated with negative, disempowering meanings that are used to identify whole persons as if “all they are” is an addict or alcoholic. These labels can go beyond indication of the mental health condition itself and stigmatize the individual as irrecoverable, deficient, or defective in character. 


Whether substance use disorders should be treated separately from other mental illnesses is not a question of either/or, but a more complex issue that is dependent on factors unique to the individual client. The manner by which treatment can be separated from other mental illnesses is both a matter of space (e.g., the setting of treatment—individuals with substance use disorders are separated from individuals with other mental illnesses) and time (e.g., the singular concern of substance use is the primary target of treatment interventions versus targeting other mental illnesses with the same client during session). Individuals with substance use disorders have unique needs different from those with other mental illnesses. A client’s needs are best understood by gaining a thorough understanding of the client’s history and a substance abuse assessment. Ideally, a treatment plan is then developed according to the identified needs of the client. 


Using the medical field as a point of comparison, it is true that not all physical health issues can be addressed by one’s general practitioner. Therefore, another service provider, a specialist, is identified as a point of referral. In a similar way, substance use treatment facilities, specific support groups, and treatment modalities that offer more specialized care can be indicated. Although treatment models that originated for use with other mental illnesses—such cognitive behavioral therapy (CBT), for example—have been adapted for use with clients with substance use disorders, the techniques or methods involved can look very different (Carroll, 1998). The intention behind recognizing this “similar, yet different” dynamic in the treatment of substance use issues is to remain focused on how a particular client may or may not benefit from separate treatment of their conditions, and whether it is warranted.


The reality that an individual can be “dually diagnosed” with both a substance use disorder and another mental disorder, such as a mood disorder, brings to light further complexities that must be addressed. If an individual is dually diagnosed, it is sometimes the unfortunate case that they are passed back and forth between a service provider that treats the substance use and another service provider that treats the other disorder. It can also be harmful when these individuals are refused treatment by service providers because of the dual nature of their diagnosis (NAMI, 2014). Whether one treats the substance use disorder before or after other concerns is, again, a complex question. Depending on the severity of impairment in functioning and client motivation, the need to reduce or eliminate the substance use could be a priority of treatment or looked at as secondary to other, overshadowing diagnoses. A client with a dual diagnosis should not be treated as if the other diagnosis does not exist, but with awareness of the inextricable link between the symptomology of each mental illness.


Best Practices   


Best practices for treating substance use disorders remain a challenge for mental health practitioners. The identification of such practices for clients who present dually with substance abuse and a mental illness has undergone much iteration in the substance abuse and mental health communities. Such practices offer a glimmer of hope to those in the field working on these issues as well as for clients who are attempting to find solace and healing with their illnesses. Many approaches to treating co-occurring disorders that do not meet strict standards of evidence are nevertheless commonly accepted and believed to be effective based on the best available research, clinical expertise, individual values, common sense, and a belief in human dignity (SAMHSA, 2009). Therefore, it is almost necessary for clinicians and practitioners to utilize practices that are available to them. It is also important to note that best practices will also have to incorporate suitable options for insurance and financing of such operations as well as key imperatives for program settings and structures of such facilities. 


SAMHSA and the National Institute on Drug Abuse (NIDA) have researched and established best practices for these populations. NIDA has highlighted best practices in working with co-occurring conditions of substance abuse and mental illnesses that are categorized into two primary sections; one highlights psychotherapy approaches that work well with a particular group, while the other section speaks to the integration of substance abuse treatment and mental health services. Within therapeutic references in working with patients with comorbid conditions there are those that distinguish best approaches for adolescents and adults, albeit separately. There are more prevalent co-occurring illnesses, such as schizophrenia and smoking and alcohol and depression that have recommended approaches when working with said populations. Lastly, age and gender are also considered in the development of best practices for treatment of dual diagnoses. Steady progress is being made through research on new and existing treatment options for co-morbid conditions, and through health service research on implementation of appropriate screening and treatment within a variety of settings, including criminal justice systems (NIDA, 2010).


Psychotherapies for Adolescents   


The following are promising behavioral therapies for adolescents with comorbid conditions. Each therapeutic approach is able to work with the substance abuse alongside an adolescent’s subsequent mental illness. Aside from the following therapies, some evidence also suggests the utility of incorporating therapeutic communities (TCs) for adolescents who have been in treatment for substance abuse and related problems (NIDA, 2010).


Multisystemic Therapy (MST)  


MST targets key factors—attitudes, family, peer pressure, school and neighborhood culture—associated with serious antisocial behavior in children and adolescents who abuse drugs.


Brief Strategic Family Therapy (BSFT)  


BSFT targets family interactions that are thought to maintain or exacerbate adolescent drug abuse and other co-occurring problem behaviors.


Cognitive Behavioral Therapy (CBT)  


CBT is the most effective psychotherapy for children and adolescents with anxiety and mood disorders, and also shows strong efficacy for substance abusers.


Psychotherapies for Adults  


The following are favorable behavioral therapies for adults with comorbid conditions and there are unique benefits associated with each approach (NIDA, 2010). In addition to this list, CBT has also been shown to be effective for adult populations suffering from drug use disorders and a range of other psychiatric problems.


Assertive Community Treatment (ACT)  


ACT integrates the behavioral treatment of severe mental disorders, such as schizophrenia, and co-occurring substance use disorders


Dialectical Behavior Therapy (DBT)  


DBT is designed to specifically reduce self-harm behaviors, including drug abuse. 


Exposure Therapy  


Exposure therapy is a behavioral treatment for use with anxiety disorders, which involves repeated exposure to or confrontation with a feared situation, object, traumatic event or memory. Several studies suggest that exposure therapy may be useful for individuals with co- morbid PTSD and cocaine addiction, although retention in treatment is difficult (NIDA, 2010).


Therapeutic Communities (TCs)  


TCs focus on the resocialization of the individual and use broad-based community programs as active components of treatment


Integrated Group Therapy (IGT)  


IGT is a new treatment developed specifically for patients with bipolar disorder and drug addiction, designed to address both problems simultaneously. 


Most clinicians and researchers agree that broad spectrum diagnoses and concurrent therapy will lead to more positive outcomes for patients with comorbid conditions (NIDA, 2010). There are similarities in evidence-based treatments or best practices for both adolescents and adults that show promise in treating both the substance use and the co-occurring illness. As the research continues to develop, more psychotherapies may be added to the list of recommended practices.


Federal Responses  


The collaboration between the National Association of State Alcohol and Drug Abuse Directors and the National Association of State Mental Health Program Directors in their scientific pursuit of more effective treatment interventions for people with a co-occurring disorder has produced a national effort to


  • foster improvements in treatment
  • provide a classification of treatment settings
  • reduce the stigma associated with mental disorders
  • and increase the acceptance of substance abuse and mental health concerns as a standard part of health care information gathering (Cherry, 2008). 




SAMHSA’s reports seek to investigate the best methods of bridging science and treatment for people with co-occurring disorders. According to their guidelines, the standards for treatment should be as follows: consumer driven; delivered from an integrated system of care that fosters an equitable distribution of services; that they are the best recovery practices available; welcoming and based on a no wrong door concept; and culturally competent (Cherry, 2008). The ability to enter into different systems and/or services that have the best intentions for the client at stake will allow for best methods in treating these individuals. Coordination of services amongst these systems will increase the likelihood effective outcomes for clients.


Integrated treatment means that the same clinicians or teams of clinicians, working in one setting, provide appropriate mental health and substance abuse interventions in a coordinated fashion (SAMSHA, 2014). This should also include effective medications for dual diagnoses. Such medications exist for treating opioid, alcohol, and nicotine addictions and for alleviating the symptoms of many other mental disorders, yet most have not been well studied in comorbid populations (NIDA, 2010).




Historical reviews of effective treatment modalities for people who have co-occurring diseases, such as substance dependence and mental illness, show a fierce debate between two systems that have only in the recent decades concluded that an integrated approach would be one best suited for all. However this is not a simple answer, as having both entities and trains of thought combined into one system must be one that appreciates and thoroughly understands the nuances of each. This is in large part due to the fact that generally people who have a substance use disorder and a mental illness tend to have more severe symptoms (NIDA, 2010).  


Social service systems have not been well designed to treat persons with co-occurring illnesses. There are substance abuse treatment facilities that mandate clients, who may also have a co-occurring mental illness, to detox in order for them to receive treatment. NAMI claims that


treatment programs designed for people whose problems are primarily substance abuse are generally not recommended for people who also have a mental illness as these programs tend to be confrontational and coercive and most people with severe mental illnesses are too fragile to benefit from them (2014, pp. 5). 


If these clients are served at a mental health clinic and present with a substance use problem, they may be told to come back when they have abstained for an established period of time. Traditional mental health treatment programs often offer services that are contingent upon clients’ abstinence from alcohol and other drugs (Mancini, Hardiman, & Eversman, 2008). Clients are referred back and forth between treatments, in what some have called “ping-pong” therapy (NAMI, 2014). Desirable programs for this population should take a more gradual approach, where clients with a dual-diagnosis can proceed at their own pace in treatment (NAMI, 2014).


NIDA states that “although research supports the need for comprehensive treatment to address co-morbidity, provision of such treatment can be problematic” (2010, pp. 9). As previously mentioned, there are different systems that address different disorders. Physicians and mental health professionals are most often the front line of treatment for mental disorders, whereas drug abuse treatment is provided in assorted venues by a mix of health care professions (NIDA, 2010). Some substance abuse treatment centers ban the use of medications in their facilities, for instance, with those who may also be suffering from a mental illness (NIDA, 2010). It is widely known that the criminal justice system carries a significant weight of persons with mental disorders, many of whom could meet the criteria for multiple diagnoses. It is estimated that about 45 percent of offenders in state and local prisons and jails have a mental health problem comorbid with substance abuse or addiction (NIDA, 2010). Having an integrated approach in such a setting could be the perfect incubator to test the effectiveness of dual services.




Cherry believes that the “substance abuse treatment and mental health treatment fields are not compatible, that they cannot be integrated effectively unless treatment philosophies and policies in both fields are willing to change, and that neither field has developed a set of treatment interventions sufficient to recommend either of them in their entirety” (2008, pp. 10). What are needed are hybrid programs that address both illnesses together, especially at a local level, which requires considerable advocacy efforts (NAMI, 2014). 


Federal grants through governmental agencies have also been able to show effectiveness to lawmakers on the value of integrating such systems as well as the cost effectiveness (SAMSHA, 2014). More recently, researchers and policy makers have begun to make the important distinction between integrated services and integrated systems involving fundamental changes in the way agencies share information, resources, and clients (SAMSHA, 2014). Policy approaches that may aid in integration have components such as flexible financing, bridging treatment philosophy differences, modifying administrative oversight, and accountability practices. However, because state mental health resources are targeted to those with severe mental disorders and the Medicaid-eligible, access to public health services can be limited (Burnam & Watkins, 2006). These challenges can hopefully be overcome with the Affordable Care Act and discussions about the evolvement of Medicaid.  




Distinguishing whether substance use disorders are fundamentally different from other mental disorders is a complex task with many stakeholders. How substance use disorders are defined and conceptualized have treatment and policy implications. Substance use disorder is recognized by the DSM-5 as its own mental disorder diagnosis, however, substance use disorders and co-occurring mental disorders has become a topic of great interest and debate. Several factors play a role in how substance use disorders can be characterized as “similar, yet different” from other typical mental illnesses. The unique needs of clients who present with dual diagnoses or who require specialized substance abuse treatment speak to the sense that substance use disorders have unique characteristics that are differentiated from other typical mental illnesses. 


Systemically, the present political and financial infrastructure recognizes this differentiation via policy-making and treatment of substance abuse as an issue to itself. Best practices to meet the unique needs of these clients are vast and subjective, in some cases, and are based upon which system the client chooses to pursue. Effective approaches for substance abuse only will likely continue to incorporate the use of self-help or support groups and, in some instances, medications. Psychotherapies that have been utilized with this population continue to glean results with comorbid clients suffering from substance use and a mental illness. The government’s response to treat substance use is through funding mechanisms which will allow researchers to find the evidence-based treatments for this population. Grantees such as SAMSHA and NIDA are able to create programs based on their findings which offer a glimmer of hope for this population. Overall, regardless of how substance use disorder is differentiated from other typical mental illnesses, efforts to ensure competent treatment and care of the unique needs of this population are an ongoing priority with the substance abuse treatment community. 


Acknowledgements: This work was supported by the Community-Academic Partnership on Addiction (CAPA).






American Psychiatric Association (APA). (2013) Diagnostic and statistical manual of mental disorders (5th ed.). Arlington, VA: American Psychiatric Publishing. 
Burnam, M., & Watkins, K. E. (2006). Substance abuse with mental disorders: Specialized public systems and integrated care. Health Affairs, 25(3), 648–58.    
Carroll, K. M. (1998). A cognitive-behavioral approach: Treating cocaine addiction. Retrieved from http://archives.drugabuse.gov/TXManuals/CBT/CBT1.html
Cherry, A. L. (2008). Mixing oil and water: Integrating mental health and addiction services to treat people with a co-occurring disorder. International Journal of Mental Health & Addiction, 6(3), 407–20. 
Fisher, G. L., & Harrison, T. C. (2012). Substance abuse: Information for school counselors, social workers, therapists, and counselors (5th ed.). Upper Saddle River, NJ: Pearson.
Mancini, M. A., Hardiman, E. R., & Eversman, M. H. (2008). A review of the compatibility of harm-reduction and recovery-oriented best practices for dual disorders. Best Practices in Mental Health, 4(2), 99–113.
National Alliance on Mental Illness (NAMI). (2013). Mental illness facts and numbers. Retrieved from http://www.nami.org/factsheets/mentalillness_factsheet.pdf
National Alliance on Mental Illness (NAMI). (2014). Dual diagnosis: Substance abuse and mental illness. Retrieved from http://www.nami.org/Content/NavigationMenu/Inform_Yourself/About_Mental_Illness/By_Illness/Dual_Diagnosis_Substance_Abuse_and_Mental_Illness.htm
National Institute of Mental Health (NIMH). (2012). Serious mental illness (SMI) among adults. Retrieved from http://www.nimh.nih.gov/statistics/SMI_AASR.shtml
National Institute of Mental Health (NIMH). (2014). What is schizophrenia? Retrieved from http://www.nimh.nih.gov/health/topics/schizophrenia/index.shtml#part1
National Institute on Drug Abuse (NIDA). (2010). Comorbidity: Addiction and other mental illnesses. Retrieved from http://www.drugabuse.gov/sites/default/files/rrcomorbidity.pdf
Office on Child Abuse and Neglect. (2009). Treating substance use disorders. Retrieved from https://www.childwelfare.gov/pubs/usermanuals/substanceuse/chapterfive.cfm
Substance Abuse and Mental Health Services Administration (SAMHSA). (2009). How to use the evidence-based practices KITs: Integrated treatment for co-occurring disorders. Retrieved from http://store.samhsa.gov/shin/content/SMA08-4367/HowtoUseEBPKITS-ITC.pdf
Substance Abuse and Mental Health Services Administration (SAMHSA). (2013). Results from the 2012 national survey on drug use and health: Mental health findings. Retrieved from http://www.samhsa.gov/data/NSDUH/2k12MH_FindingsandDetTables/2K12MHF/NSDUHmhfr2012.htm
Substance Abuse and Mental Health Services Administration (SAMHSA). (2014). Crisis services: Effectiveness, cost-effectiveness, and funding strategies. Retrieved from http://store.samhsa.gov/shin/content//SMA14-4848/SMA14-4848.pdf