Clinical Textbook of Addictive Disorders 3rd ed - R. Frances, S. Miller, A. Mack (Guilford, 2005) WW

12. Co-Occurring Substance Use Disorders and Other Psychiatric Disorders 277is independent of substance use or related to intoxication or withdrawal.For example, when examining a patient who has a long history of alcoholdependence and depressive symptoms, it can be difficult to determinewhether the depressive symptoms result from the direct pharmacologicaleffects of alcohol, the many losses experienced as a result of the alcohol use,feelings of discouragement about the inability to stop drinking, or an independentmood disorder. Other etiologies, such as metabolic disturbances,head trauma, and personality disorders, must also be considered in the differentialdiagnosis of depressive symptoms in alcohol-dependent patients (Jaffe& Ciraulo, 1986).Given these considerations, one could ideally establish diagnostic rules toassist in determining whether a psychiatric syndrome is due to substance use orrepresents a separate and independent disorder. For example, some cliniciansmay establish a rule that a patient must be abstinent from alcohol and drugs forat least 4 weeks before they can make a diagnosis. Unfortunately, one does notalways have the luxury of observing such lengthy abstinent periods (either byhistorical report or in the present) to assess this. In such circumstances, guidelines,as opposed to strict rules, can be helpful. For example, several studieshave indicated that for alcoholics with major depression, treating the depressioncan have a positive impact on drinking (Cornelius et al., 1997; Greenfieldet al., 1998). Thus, while DSM-IV-TR (American Psychiatric Association,2000) criteria for substance-induced mood disorder suggest at least 4 weeks ofobservation during abstinence before a clinician can diagnose an independentpsychiatric disorder, it also recommends that clinicians should diagnose an independentdisorder if the symptoms are qualitatively or quantitatively not whatone would expect, given the amount and duration of the substance use. Certaindisorders, such as eating disorders and PTSD, can be diagnosed readily, even inthe context of substance use or withdrawal, since their symptoms do not closelyresemble substance-related syndromes. Indeed, for a diagnosis such as PTSD,which tends to be underdiagnosed in SUD patients, the greater danger is todelay diagnosis; waiting for a period of abstinence may prevent needed treatmentfor the co-occurring disorder (Najavits, 2004).Finally, clinicians should consider whether the patient’s symptoms arewhat would be expected upon discontinuation of the abused substance. If thereis considerable overlap between the observed symptoms and what one wouldexpect from the drug discontinuation syndrome, then the clinician should waituntil either (1) the symptoms resolve, or (2) the symptoms no longer are consistentwith what one would expect from drug cessation (i.e., the syndrome onewould expect to see after 1 week vs. 1 month of alcohol abstinence). Alternatively,if there is little overlap between the symptoms observed and theexpected abstinence syndrome (e.g., bulimia nervosa in an opioid-dependentpatient), then the diagnosis can be made without waiting.