Anxiety in the Context of Substance Use

By | July 1, 2012

Complaints about anxiety are so common among persons who abuse substances that substance abuse has sometimes been characterized as a misguided attempt to self-medicate these symptoms (). Anxiety disorders, as defined by DSM-IV-TR (), occur in only a minority of persons who abuse substances. In contrast to depression, the etiology, pathogenesis, and treatment of anxiety disorders in persons who abuse substances have received relatively little attention. Until recently, much of the literature focused on the problem of the false-positive diagnosis of an anxiety disorder in persons who abuse substances () and the danger of benzodiazepine dependence (1997). The advances in the nosology, neurobiology, and treatment of anxiety disorders that are described in other chapters of this book have had little effect on the thinking about these disorders in the context of substance abuse and even less on treatment or prevention. The purpose of this chapter is to summarize our knowledge about the diagnosis, pathogenesis, and treatment of anxiety disorders that occur in individuals with current or lifetime histories of substance-related disorders and to pose questions for future research.

Anxiety States in Persons Who Abuse Substances

Anxiety disorders do not account for most of the complaints about anxious feelings among persons who abuse substances. A large portion of these complaints are related to intoxication or withdrawal states per se. Substances as diverse as cocaine, marijuana, caffeine, and alcohol may induce anxious feelings, physical signs of anxiety, or even frank panic. Withdrawal after the chronic exposure to virtually any addictive substance provokes anxiety. In withdrawal syndromes from some psychoactive substances, such as opioids, alcohol, or benzodiazepines, the anxiety symptoms are part of a cluster of dysphoric symptoms and physical signs of arousal. However, for other drugs such as marijuana or cocaine, the anxiety symptoms may be more subtle. When anxiety symptoms during intoxication or withdrawal take on the pattern of an anxiety disorder and go beyond the normal bounds of intoxication or withdrawal, they are classified as a substance-induced anxiety disorder and further labeled by the specific substance.

Studies of the neurobiology of anxiety disorders and withdrawal syndromes show some interesting convergences. Several brain regions, such as the amygdala, paraventricular nucleus, locus coeruleus, and mesoprefrontal cortex, have been implicated in anxiety states as well as withdrawal syndromes and drug craving states (1994). In humans, the infusion of serotonergic agonists may provoke anxiety in panic patients and cravings in alcoholic persons (). The infusion of yohimbine may provoke anxiety and flashbacks in patients with posttraumatic stress disorder () and anxiety in very recently abstinent persons who were addicted to cocaine (). Withdrawal states, substance craving, and anxiety states therefore resemble one another phenomenologically and neurobiologically.

Even after the period of early withdrawal, treatment-seeking persons who abuse substances continue to have high levels of anxious feelings in conjunction with other negative feelings such as depression, tension, hostility, and shame (1997). Sutherland () recently showed that these “traits,” generally labeled neuroticism by personality theorists, persist at high levels for several months after treatment but decline somewhat after approximately 6 months of abstinence. This finding corresponds with the clinical observations of specialists in addiction medicine (1996). No evidence shows that psychopharmacological treatment of anxious feelings that occur outside the parameters of a definable anxiety disorder enhances the retention or outcome in treatment for substance use disorders. When persons who abuse substances require intensive medical treatment, however, the short-term use of anxiolytic agents may facilitate adherence to treatment and can be justified on that basis.

Reliability and Validity of Psychiatric Diagnoses Comorbid With Substance Use Disorder

Pathogenesis of Comorbid Anxiety and Substance Use Disorders

Treatment of Comorbid Anxiety and Substance Use Disorders

Prevention

Of the anxiety disorders, social phobia usually occurs before the onset of substance use problems. It is not certain whether adolescents with social phobia go on to develop substance use disorders at a higher level than do individuals without psychiatric illness. Because substance use disorders can be prevented by restricting or postponing exposure to psychoactive substances, it might be prudent to identify adolescents with social phobia and tailor substance use prevention (perhaps including treatment for social phobia) to them. A special case of this applies to young gay men with social phobia who may rely on alcohol or party drugs to overcome their shyness and thereby diminish their adherence to safer-sex practices.

Suggestions for Different Treatment Scenarios

When individuals with moderate to severe dependence are in the early phases of abstinence, the main focus of treatment is learning to tolerate abstinence, to make plans to stay in treatment, and to avoid relapse. This early phase of treatment may be complicated and undermined by a heavy burden of anxiety symptoms such as panic attacks, intrusive posttraumatic memories, obsessions or compulsions, generalized worry and tension, or extreme fear of judgment in social interaction. In this situation, psychotherapy focused on anxiety is unlikely to help simply because of the need to focus on addiction. However, medications that would be expected to treat anxiety symptoms in nonaddicted persons may reduce the burden of symptoms and thus help the recovering individual to focus on recovery. During this phase, we generally opt for agents that have no abuse liability, but in some cases the anxiety symptoms are so severe that benzodiazepines should be considered. Secondary effects of anxiety such as fear of perceived criticism in group treatment, severe avoidance, or the need to exert unrealistic levels of control often jeopardize substance abuse treatment. Early identification of these problems is essential.

Once the individual has gained some stability in abstinence, has affiliated with long-term treatment, and has learned to implement relapse prevention and coping skills, it is time to address the role of anxiety in the individual’s life and to understand how symptoms of anxiety interplay with addiction.

Individuals with anxiety disorders who perceive that alcohol, sedative, or marijuana use relieves anxiety may not be willing to consider that such use could constitute abuse or dependence and may consider the abused substance to have fewer problems than do standard anxiolytic treatments. Sometimes, they are willing to consider anxiolytic treatment but are not willing to give up the abused substance. In these cases, education about anxiety, patience, and flexibility usually carries the day, so the initial focus should be on retention in treatment.

Recovered patients with long-term abstinence who develop anxiety disorders often are concerned about the possibility of relapse or misuse of medication. Physicians generally avoid agents that have known abuse liability, but when these agents are necessary, careful monitoring of appropriate medication use is helpful.

Conclusion

Anxiety disorders and substance use disorders are both common; therefore, many individuals have both disorders. The diagnosis and treatment of anxiety disorders in persons who abuse substances are confounded by the ubiquitous nature of anxiety symptoms among persons who abuse substances, by the poor validity and modest reliability of the diagnosis of anxiety disorders in the presence of substance abuse, and by the absence of well-designed clinical trials on the treatment of comorbid anxiety disorders. No clear evidence indicates that anxiety disorders and substance use disorders share a common genetic etiology, but a good deal of evidence suggests that the two types of disorders are related to each other pathogenetically in a complex rather than simple way, as suggested by the “self-medication” hypothesis. Special psychopharmacological or psychological treatment of anxiety symptoms in persons who abuse substances does not seem warranted. Psychopharmacological and focused psychological treatments of comorbid anxiety disorder seem prudent, but we do not have a reliable evidence base to guide such treatment. Algorithms for psychopharmacological management of anxiety disorders in persons who abuse substances are by and large similar to those in persons who do not abuse substances, with the exception that benzodiazepines and monoamine oxidase inhibitors generally are avoided. Whether specific types of anxiety disorder are also markers for meaningful subgroups of persons who abuse substances is an intriguing question.

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