A Comparison of Factors Associated with Substance-Induced Versus Independent Depressions * (Report‪)‬

THE ALCOHOL-USE DISORDERS (AUDs) and substance-use disorders (SUDs) of abuse and dependence are often accompanied by symptoms of additional psychiatric syndromes. This is especially true regarding psychotic symptoms among stimulant-dependent individuals and depressive syndromes in alcoholics (Altamura et al., 1990; Brown et al., 1995; Hasin et al., 2002; Nurnberger et al., 2004). In some cases, an independent psychiatric condition (i.e., a disorder that is not only seen temporarily in the context of alcohol or relevant drug intoxication or withdrawal) may have contributed to the risk for substance-use patterns, as can be seen with antisocial personality disorder (ASPD), schizophrenia, and manic depressive disease (Kessler et al., 1997; Slutske et al., 1998; Winokur et al., 1996). In these instances, as described in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR; American Psychiatric Association, 2000), the independent psychiatric disorders (e.g., ASPD, schizophrenia, or manic depressive disease) can usually be observed before the onset of abuse or dependence on a relevant substance and/or remain manifest after extended periods of abstinence. Optimal treatment for these independent psychiatric conditions requires appropriate interventions to address the psychiatric disorder, as well as steps to help individuals abstain from alcohol and illicit drugs to optimize their response to treatments for their psychiatric syndrome. Intoxication or withdrawal associated with many of the substances of abuse (including alcohol) can also produce temporary substance-induced psychiatric conditions that closely resemble independent psychiatric syndromes. This makes substance use an important part of the differential diagnosis in evaluating patients with these psychiatric conditions (Schuckit, 2006). For example, temporary, but intense, depressions can be induced in research subjects consuming up to 20 drinks per day (Isbell et al., 1955; Tamerin et al., 1970) and are seen in a third or more of treatment-seeking, alcohol-dependent patients (Gilder et al., 2004; Schuckit et al., 1997). However, about half of these depressions developed only in the context of heavy drinking and markedly improved within 2-4 weeks of abstinence (Brown et al., 1995; Davidson, 1995; Kiefer and Barocka, 1999; Willenbring, 1986). Such substance-induced changes in mood may explain a substantial proportion of the major depressive episodes (MDEs) observed among alcoholics, and once these are considered, the rate of independent depressions may not be much higher among alcoholics than in the general population.