UpToDate
Official reprint from UpToDate®
www.uptodate.com ©2017 UpToDate®

Co-occurring schizophrenia and substance use disorder: Epidemiology, pathogenesis, clinical manifestations, course, assessment and diagnosis

Authors
E Cabrina Campbell, MD
Stanley N Caroff, MD
Stephan C Mann, MD, DLFAPA
Section Editors
Andrew J Saxon, MD
Stephen Marder, MD
Deputy Editor
Richard Hermann, MD

INTRODUCTION

Schizophrenia and addiction are both chronic disorders with serious complications, consequences, and costs for individuals and society. Both conditions are associated with poor adherence to treatment and poorer outcomes when the co-occurring disorder is present.

Some of the symptoms of schizophrenia overlap with symptoms of intoxication, chronic use, or withdrawal from alcohol or other drugs. Family history and the temporal relationship of symptoms can help to distinguish patients with a substance use disorder (SUD) alone from co-occurring schizophrenia and SUD.

The psychiatric diagnoses, substance abuse and substance dependence, in DSM-IV-TR were replaced by one diagnosis, substance use disorder, in DSM-5 [1]. Although the crosswalk between DSM-IV and DSM-5 disorders is imprecise, substance dependence is approximately comparable to substance use disorder, moderate to severe subtype, while substance abuse is similar to the mild subtype.

The epidemiology, pathogenesis, clinical manifestations, course, assessment, and diagnosis of schizophrenia and substance use disorder are described here. Treatment of co-occurring schizophrenia and substance use disorder are described separately. The epidemiology, pathogenesis, clinical manifestations, course, assessment, diagnosis and treatment of schizophrenia occurring alone and substance use disorder occurring alone are also discussed separately. (See "Psychosocial interventions for co-occurring schizophrenia and substance use disorder" and "Schizophrenia in adults: Epidemiology and pathogenesis" and "Pharmacotherapy for schizophrenia: Acute and maintenance phase treatment" and "Schizophrenia in adults: Clinical manifestations, course, assessment, and diagnosis" and "Pharmacotherapy for schizophrenia: Side effect management" and "Opioid use disorder: Epidemiology, pharmacology, clinical manifestations, course, screening, assessment, and diagnosis" and "Cannabis use and disorder: Epidemiology, comorbidity, health consequences, and medico-legal status" and "Cannabis use and disorder: Clinical manifestations, course, assessment, and diagnosis" and "Risky drinking and alcohol use disorder: Epidemiology, pathogenesis, clinical manifestations, course, assessment, and diagnosis" and "Cocaine use disorder in adults: Epidemiology, pharmacology, clinical manifestations, medical consequences, and diagnosis".)

EPIDEMIOLOGY

Prevalence — Epidemiologic studies have generally shown that the prevalence of substance use disorder (SUD) is elevated in persons with schizophrenia compared with the general population. As examples, in a study of substance use among 9142 individuals with severe psychotic disorders, including 5586 subjects with schizophrenia or schizoaffective disorder, the odds of nicotine (smoking), alcohol, marijuana, and other drug use were higher (odds ratios = 3.5 to 4.6) in patients with psychosis compared with 10,195 nonpsychiatric controls [2]. Rates of substance use varied among subgroups based on age, gender, and race or ethnicity. Having a psychotic disorder further increased the odds of substance use in each subgroup. The lifetime prevalence of the DSM-IV-TR disorders substance abuse and substance dependence among patients with schizophrenia has been estimated to range from 47 to 59 percent in the United States , compared with 16 percent in the general population [3-5]. Differences between schizophrenia patients and normal controls in substance use may be diminished when the effects of low socioeconomic status (common among schizophrenia patients) is taken into account [6-14]. High rates of co-occurrence have also been observed internationally (eg, in Australia, Switzerland, Italy, Germany, England, Turkey) [15-17]. Many with these co-occurring disorders used two or more substances.  

                

Subscribers log in here

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:
Literature review current through: Aug 2017. | This topic last updated: Sep 15, 2017.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2017 UpToDate, Inc.
References
Top
  1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), American Psychiatric Association, Arlington, VA 2013.
  2. Hartz SM, Pato CN, Medeiros H, et al. Comorbidity of severe psychotic disorders with measures of substance use. JAMA Psychiatry 2014; 71:248.
  3. Regier DA, Farmer ME, Rae DS, et al. Comorbidity of mental disorders with alcohol and other drug abuse. Results from the Epidemiologic Catchment Area (ECA) Study. JAMA 1990; 264:2511.
  4. Kendler KS, Gallagher TJ, Abelson JM, Kessler RC. Lifetime prevalence, demographic risk factors, and diagnostic validity of nonaffective psychosis as assessed in a US community sample. The National Comorbidity Survey. Arch Gen Psychiatry 1996; 53:1022.
  5. Thoma P, Daum I. Comorbid substance use disorder in schizophrenia: a selective overview of neurobiological and cognitive underpinnings. Psychiatry Clin Neurosci 2013; 67:367.
  6. Sara GE, Large MM, Matheson SL, et al. Stimulant use disorders in people with psychosis: a meta-analysis of rate and factors affecting variation. Aust N Z J Psychiatry 2015; 49:106.
  7. Fryers T, Melzer D, Jenkins R, Brugha T. The distribution of the common mental disorders: social inequalities in Europe. Clin Pract Epidemiol Ment Health 2005; 1:14.
  8. Scott KM, Al-Hamzawi AO, Andrade LH, et al. Associations between subjective social status and DSM-IV mental disorders: results from the World Mental Health surveys. JAMA Psychiatry 2014; 71:1400.
  9. Gara MA, Vega WA, Arndt S, et al. Influence of patient race and ethnicity on clinical assessment in patients with affective disorders. Arch Gen Psychiatry 2012; 69:593.
  10. Rost K, Hsieh YP, Xu S, et al. Potential disparities in the management of schizophrenia in the United States. Psychiatr Serv 2011; 62:613.
  11. Brown T, Platt S, Amos A. Equity impact of European individual-level smoking cessation interventions to reduce smoking in adults: a systematic review. Eur J Public Health 2014; 24:551.
  12. Bull ER, Dombrowski SU, McCleary N, Johnston M. Are interventions for low-income groups effective in changing healthy eating, physical activity and smoking behaviours? A systematic review and meta-analysis. BMJ Open 2014; 4:e006046.
  13. Lindenberg CS, Solorzano RM, Bear D, et al. Reducing substance use and risky sexual behavior among young, low-income Mexican-American women: comparsion of two interventions. Appl Nurs Res 2012; 15:137.
  14. Bradizza CM, Stasiewicz PR, Paas ND. Relapse to alcohol and drug use among individuals diagnosed with co-occurring mental health and substance use disorders: a review. Clin Psychol Rev 2006; 26:162.
  15. Buckley PF. Prevalence and consequences of the dual diagnosis of substance abuse and severe mental illness. J Clin Psychiatry 2006; 67 Suppl 7:5.
  16. Morgan VA, Waterreus A, Carr V, et al. Responding to challenges for people with psychotic illness: Updated evidence from the Survey of High Impact Psychosis. Aust N Z J Psychiatry 2017; 51:124.
  17. Tekin Uludağ Y, Güleç G. Prevalence of Substance Use in Patients Diagnosed with Schizophrenia. Noro Psikiyatr Ars 2016; 53:4.
  18. Maremmani AG, Bacciardi S, Gehring ND, et al. Substance Use Among Homeless Individuals With Schizophrenia and Bipolar Disorder. J Nerv Ment Dis 2017; 205:173.
  19. Libuy N, de Angel V, Ibáñez C, et al. The relative prevalence of schizophrenia among cannabis and cocaine users attending addiction services. Schizophr Res 2017.
  20. Chapman S, Ragg M, McGeechan K. Citation bias in reported smoking prevalence in people with schizophrenia. Aust N Z J Psychiatry 2009; 43:277.
  21. Ziedonis D, Williams JM, Smelson D. Serious mental illness and tobacco addiction: a model program to address this common but neglected issue. Am J Med Sci 2003; 326:223.
  22. Koskinen J, Löhönen J, Koponen H, et al. Prevalence of alcohol use disorders in schizophrenia--a systematic review and meta-analysis. Acta Psychiatr Scand 2009; 120:85.
  23. Koskinen J, Löhönen J, Koponen H, et al. Rate of cannabis use disorders in clinical samples of patients with schizophrenia: a meta-analysis. Schizophr Bull 2010; 36:1115.
  24. Swartz MS, Wagner HR, Swanson JW, et al. Substance use and psychosocial functioning in schizophrenia among new enrollees in the NIMH CATIE study. Psychiatr Serv 2006; 57:1110.
  25. Kivimies K, Repo-Tiihonen E, Kautiainen H, et al. Opioid abuse and hospitalization rates in patients with schizophrenia. Nord J Psychiatry 2016; 70:128.
  26. Krausz M, Verthein U, Degkwitz P. Psychiatric comorbidity in opiate addicts. Eur Addict Res 1999; 5:55.
  27. Marieczurrena R. Recovery from addiction without treatment: an interview study. Scand J Behav Ther 1996; 25:57.
  28. Chiappelli J, Chen S, Hackman A, Elliot Hong L. Evidence for differential opioid use disorder in schizophrenia in an addiction treatment population. Schizophr Res 2017.
  29. Lybrand J, Caroff S. Management of schizophrenia with substance use disorders. Psychiatr Clin North Am 2009; 32:821.
  30. Mueser KT, Essock SM, Drake RE, et al. Rural and urban differences in patients with a dual diagnosis. Schizophr Res 2001; 48:93.
  31. Tsai J, Rosenheck RA. Psychiatric comorbidity among adults with schizophrenia: a latent class analysis. Psychiatry Res 2013; 210:16.
  32. Dubertret C, Bidard I, Adès J, Gorwood P. Lifetime positive symptoms in patients with schizophrenia and cannabis abuse are partially explained by co-morbid addiction. Schizophr Res 2006; 86:284.
  33. Malchow B, Hasan A, Fusar-Poli P, et al. Cannabis abuse and brain morphology in schizophrenia: a review of the available evidence. Eur Arch Psychiatry Clin Neurosci 2013; 263:3.
  34. Mueser KT, Drake RE, Wallach MA. Dual diagnosis: a review of etiological theories. Addict Behav 1998; 23:717.
  35. Ng E, McGirr A, Wong AH, Roder JC. Using rodents to model schizophrenia and substance use comorbidity. Neurosci Biobehav Rev 2013; 37:896.
  36. Khokhar JY, Dwiel LL, Henricks AM, et al. The link between schizophrenia and substance use disorder: A unifying hypothesis. Schizophr Res 2017.
  37. Chambers RA, Bickel WK, Potenza MN. A scale-free systems theory of motivation and addiction. Neurosci Biobehav Rev 2007; 31:1017.
  38. Krystal JH, D'Souza DC, Gallinat J, et al. The vulnerability to alcohol and substance abuse in individuals diagnosed with schizophrenia. Neurotox Res 2006; 10:235.
  39. Power RA, Verweij KJ, Zuhair M, et al. Genetic predisposition to schizophrenia associated with increased use of cannabis. Mol Psychiatry 2014; 19:1201.
  40. Sherva R, Wang Q, Kranzler H, et al. Genome-wide Association Study of Cannabis Dependence Severity, Novel Risk Variants, and Shared Genetic Risks. JAMA Psychiatry 2016; 73:472.
  41. Hartz SM, Horton AC, Oehlert M, et al. Association Between Substance Use Disorder and Polygenic Liability to Schizophrenia. Biol Psychiatry 2017.
  42. Feng Y. Convergence and divergence in the etiology of myelin impairment in psychiatric disorders and drug addiction. Neurochem Res 2008; 33:1940.
  43. Chambers RA, Krystal JH, Self DW. A neurobiological basis for substance abuse comorbidity in schizophrenia. Biol Psychiatry 2001; 50:71.
  44. Volkow ND. Substance use disorders in schizophrenia--clinical implications of comorbidity. Schizophr Bull 2009; 35:469.
  45. Carrà G, Nicolini G, Crocamo C, et al. Executive control in schizophrenia: a preliminary study on the moderating role of COMT Val158Met for comorbid alcohol and substance use disorders. Nord J Psychiatry 2017; 71:332.
  46. Peters SK, Dunlop K, Downar J. Cortico-Striatal-Thalamic Loop Circuits of the Salience Network: A Central Pathway in Psychiatric Disease and Treatment. Front Syst Neurosci 2016; 10:104.
  47. McTeague LM, Huemer J, Carreon DM, et al. Identification of Common Neural Circuit Disruptions in Cognitive Control Across Psychiatric Disorders. Am J Psychiatry 2017; 174:676.
  48. Duijkers JC, Vissers CT, Egger JI. Unraveling Executive Functioning in Dual Diagnosis. Front Psychol 2016; 7:979.
  49. Peckham E, Bradshaw TJ, Brabyn S, et al. Exploring why people with SMI smoke and why they may want to quit: baseline data from the SCIMITAR RCT. J Psychiatr Ment Health Nurs 2016; 23:282.
  50. Westermeyer J. Comorbid schizophrenia and substance abuse: a review of epidemiology and course. Am J Addict 2006; 15:345.
  51. Brunette MF, Mueser KT, Babbin S, et al. Demographic and clinical correlates of substance use disorders in first episode psychosis. Schizophr Res 2017.
  52. Carney R, Yung AR, Amminger GP, et al. Substance use in youth at risk for psychosis. Schizophr Res 2017; 181:23.
  53. Hodgins S, Larm P, Westerman J. Individuals developing schizophrenia are hidden among adolescent substance misusers. Psychol Med 2016; 46:3041.
  54. Wilkinson ST, Radhakrishnan R, D'Souza DC. Impact of Cannabis Use on the Development of Psychotic Disorders. Curr Addict Rep 2014; 1:115.
  55. Samaha AN. Can antipsychotic treatment contribute to drug addiction in schizophrenia? Prog Neuropsychopharmacol Biol Psychiatry 2014; 52:9.
  56. Mackowick KM, Barr MS, Wing VC, et al. Neurocognitive endophenotypes in schizophrenia: modulation by nicotinic receptor systems. Prog Neuropsychopharmacol Biol Psychiatry 2014; 52:79.
  57. Lohr JB, Flynn K. Smoking and schizophrenia. Schizophr Res 1992; 8:93.
  58. Mobascher A, Winterer G. The molecular and cellular neurobiology of nicotine abuse in schizophrenia. Pharmacopsychiatry 2008; 41 Suppl 1:S51.
  59. Volkow ND, Wang GJ, Telang F, et al. Profound decreases in dopamine release in striatum in detoxified alcoholics: possible orbitofrontal involvement. J Neurosci 2007; 27:12700.
  60. Sacco KA, Termine A, Seyal A, et al. Effects of cigarette smoking on spatial working memory and attentional deficits in schizophrenia: involvement of nicotinic receptor mechanisms. Arch Gen Psychiatry 2005; 62:649.
  61. Parikh V, Kutlu MG, Gould TJ. nAChR dysfunction as a common substrate for schizophrenia and comorbid nicotine addiction: Current trends and perspectives. Schizophr Res 2016; 171:1.
  62. Potvin S, Lungu O, Lipp O, et al. Increased ventro-medial prefrontal activations in schizophrenia smokers during cigarette cravings. Schizophr Res 2016; 173:30.
  63. Radhakrishnan R, Wilkinson ST, D'Souza DC. Gone to Pot - A Review of the Association between Cannabis and Psychosis. Front Psychiatry 2014; 5:54.
  64. Chen J, Paredes W, Lowinson JH, Gardner EL. Delta 9-tetrahydrocannabinol enhances presynaptic dopamine efflux in medial prefrontal cortex. Eur J Pharmacol 1990; 190:259.
  65. Laviolette SR, Grace AA. The roles of cannabinoid and dopamine receptor systems in neural emotional learning circuits: implications for schizophrenia and addiction. Cell Mol Life Sci 2006; 63:1597.
  66. Murray RM, Englund A, Abi-Dargham A, et al. Cannabis-associated psychosis: Neural substrate and clinical impact. Neuropharmacology 2017; 124:89.
  67. D'Souza DC, Radhakrishnan R, Sherif M, et al. Cannabinoids and Psychosis. Curr Pharm Des 2016; 22:6380.
  68. Gage SH, Jones HJ, Burgess S, et al. Assessing causality in associations between cannabis use and schizophrenia risk: a two-sample Mendelian randomization study. Psychol Med 2017; 47:971.
  69. Ho BC, Wassink TH, Ziebell S, Andreasen NC. Cannabinoid receptor 1 gene polymorphisms and marijuana misuse interactions on white matter and cognitive deficits in schizophrenia. Schizophr Res 2011; 128:66.
  70. Onwuameze OE, Nam KW, Epping EA, et al. MAPK14 and CNR1 gene variant interactions: effects on brain volume deficits in schizophrenia patients with marijuana misuse. Psychol Med 2013; 43:619.
  71. Misiak B, Stramecki F, Gawęda Ł, et al. Interactions Between Variation in Candidate Genes and Environmental Factors in the Etiology of Schizophrenia and Bipolar Disorder: a Systematic Review. Mol Neurobiol 2017.
  72. Xie P, Kranzler HR, Krystal JH, et al. Deep resequencing of 17 glutamate system genes identifies rare variants in DISC1 and GRIN2B affecting risk of opioid dependence. Addict Biol 2014; 19:955.
  73. Daglish MR, Williams TM, Wilson SJ, et al. Brain dopamine response in human opioid addiction. Br J Psychiatry 2008; 193:65.
  74. Mitrovic I, Napier TC. Mu and kappa opioid agonists modulate ventral tegmental area input to the ventral pallidum. Eur J Neurosci 2002; 15:257.
  75. Large M, Mullin K, Gupta P, et al. Systematic meta-analysis of outcomes associated with psychosis and co-morbid substance use. Aust N Z J Psychiatry 2014; 48:418.
  76. Adan A, Capella MD, Prat G, et al. Executive Functioning in Men with Schizophrenia and Substance Use Disorders. Influence of Lifetime Suicide Attempts. PLoS One 2017; 12:e0169943.
  77. Adan A, Arredondo AY, Capella MD, et al. Neurobiological underpinnings and modulating factors in schizophrenia spectrum disorders with a comorbid substance use disorder: A systematic review. Neurosci Biobehav Rev 2017; 75:361.
  78. Pulver AE, Wolyniec PS, Wagner MG, et al. An epidemiologic investigation of alcohol-dependent schizophrenics. Acta Psychiatr Scand 1989; 79:603.
  79. Manning V, Betteridge S, Wanigaratne S, et al. Cognitive impairment in dual diagnosis inpatients with schizophrenia and alcohol use disorder. Schizophr Res 2009; 114:98.
  80. Sevy S, Kay SR, Opler LA, van Praag HM. Significance of cocaine history in schizophrenia. J Nerv Ment Dis 1990; 178:642.
  81. Vergara-Moragues E, Mestre-Pintó JI, Gómez PA, et al. Can symptoms help in differential diagnosis between substance-induced vs independent psychosis in adults with a lifetime diagnosis of cocaine use disorder? Psychiatry Res 2016; 242:94.
  82. Bramness JG, Rognli EB. Psychosis induced by amphetamines. Curr Opin Psychiatry 2016; 29:236.
  83. Okada N, Takahashi K, Nishimura Y, et al. Characterizing prefrontal cortical activity during inhibition task in methamphetamine-associated psychosis versus schizophrenia: a multi-channel near-infrared spectroscopy study. Addict Biol 2016; 21:489.
  84. Green AI, Tohen MF, Hamer RM, et al. First episode schizophrenia-related psychosis and substance use disorders: acute response to olanzapine and haloperidol. Schizophr Res 2004; 66:125.
  85. Brunette MF, Mueser KT. Psychosocial interventions for the long-term management of patients with severe mental illness and co-occurring substance use disorder. J Clin Psychiatry 2006; 67 Suppl 7:10.
  86. Jones RM, Lichtenstein P, Grann M, et al. Alcohol use disorders in schizophrenia: a national cohort study of 12,653 patients. J Clin Psychiatry 2011; 72:775.
  87. Velligan DI, Sajatovic M, Hatch A, et al. Why do psychiatric patients stop antipsychotic medication? A systematic review of reasons for nonadherence to medication in patients with serious mental illness. Patient Prefer Adherence 2017; 11:449.
  88. Coentre R, Talina MC, Góis C, Figueira ML. Depressive symptoms and suicidal behavior after first-episode psychosis: A comprehensive systematic review. Psychiatry Res 2017; 253:240.
  89. Aagaard J, Buus N, Wernlund AG, et al. Clinically useful predictors for premature mortality among psychiatric patients visiting a psychiatric emergency room. Int J Soc Psychiatry 2016; 62:462.
  90. Hjorthøj C, Østergaard ML, Benros ME, et al. Impact of additive alcohol and substance use disorders on the mortality of people with schizophrenia and mood disorders. Lancet Psychiatry 2015; 2:801.
  91. Drake RE, Luciano AE, Mueser KT, et al. Longitudinal Course of Clients With Co-occurring Schizophrenia-Spectrum and Substance Use Disorders in Urban Mental Health Centers: A 7-Year Prospective Study. Schizophr Bull 2016; 42:202.
  92. Conus P, Cotton S, Schimmelmann BG, et al. Rates and predictors of 18-months remission in an epidemiological cohort of 661 patients with first-episode psychosis. Soc Psychiatry Psychiatr Epidemiol 2017.
  93. Weibell MA, Hegelstad WTV, Auestad B, et al. The Effect of Substance Use on 10-Year Outcome in First-Episode Psychosis. Schizophr Bull 2017.
  94. Maat A, Fouwels A, de Haan L. Cocaine is a major risk factor for antipsychotic induced akathisia, parkinsonism and dyskinesia. Psychopharmacol Bull 2008; 41:5.
  95. Zhornitsky S, Stip E, Pampoulova T, et al. Extrapyramidal symptoms in substance abusers with and without schizophrenia and in nonabusing patients with schizophrenia. Mov Disord 2010; 25:2188.
  96. Swartz MS, Wagner HR, Swanson JW, et al. The effectiveness of antipsychotic medications in patients who use or avoid illicit substances: results from the CATIE study. Schizophr Res 2008; 100:39.
  97. Wobrock T, Falkai P, Schneider-Axmann T, et al. Comorbid substance abuse in first-episode schizophrenia: effects on cognition and psychopathology in the EUFEST study. Schizophr Res 2013; 147:132.
  98. Rosenberg SD, Goodman LA, Osher FC, et al. Prevalence of HIV, hepatitis B, and hepatitis C in people with severe mental illness. Am J Public Health 2001; 91:31.
  99. Ziedonis DM, Smelson D, Rosenthal RN, et al. Improving the care of individuals with schizophrenia and substance use disorders: consensus recommendations. J Psychiatr Pract 2005; 11:315.
  100. Himelhoch S, Lehman A, Kreyenbuhl J, et al. Prevalence of chronic obstructive pulmonary disease among those with serious mental illness. Am J Psychiatry 2004; 161:2317.
  101. Dixon L, Postrado L, Delahanty J, et al. The association of medical comorbidity in schizophrenia with poor physical and mental health. J Nerv Ment Dis 1999; 187:496.
  102. Schmidt LM, Hesse M, Lykke J. The impact of substance use disorders on the course of schizophrenia--a 15-year follow-up study: dual diagnosis over 15 years. Schizophr Res 2011; 130:228.
  103. Stubbs B, Vancampfort D, Bobes J, et al. How can we promote smoking cessation in people with schizophrenia in practice? A clinical overview. Acta Psychiatr Scand 2015; 132:122.
  104. Institute of Medicine. Improving the Quality of Health Care for Mental and Substance-Use Conditions: Quality Chasm Series, National Academies Press, Washington DC 2006. p.210.
  105. Tiet QQ, Finney JW, Moos RH. Screening psychiatric patients for illicit drug use disorders and problems. Clin Psychol Rev 2008; 28:578.
  106. Rogers E, Sherman S. Tobacco use screening and treatment by outpatient psychiatrists before and after release of the American Psychiatric Association treatment guidelines for nicotine dependence. Am J Public Health 2014; 104:90.
  107. Fals-Stewart W, O'Farrell TJ, Freitas TT, et al. The timeline followback reports of psychoactive substance use by drug-abusing patients: psychometric properties. J Consult Clin Psychol 2000; 68:134.
  108. McLellan AT, Kushner H, Metzger D, et al. The Fifth Edition of the Addiction Severity Index. J Subst Abuse Treat 1992; 9:199.
  109. Bellack AS, Bennett ME, Gearon JS, et al. A randomized clinical trial of a new behavioral treatment for drug abuse in people with severe and persistent mental illness. Arch Gen Psychiatry 2006; 63:426.
  110. Center for Substance Abuse Treatment. Substance Abuse Treatment for Persons With Co-Occurring Disorders, Substance Abuse and Mental Health Services Administration, Rockville, MD 2005.