Anxiety disorders defined

Generalized anxiety disorder has been relatively neglected from the point of view of both health economics and pharmacoeconomics. The changing diagnostic criteria have made it difficult to compare data over time, leading researchers to focus on the more clearly defined disorders such as panic and obsessions. Drug treatment has been dominated by the benzodiazepines, usually available genetically and cheaply. However, as the final section of this chapter will show, all this is in flux. 

DSM-IV defines social anxiety disorder as an excessive fear of scrutiny by others in social situations. Refer to Table 5.9 for the diagnostic criteria for social anxiety... 

In this chapter, we consider categorical anxiety disorders as defined by the standardized diagnostic criteria of American Psychiatric Association s Diagnostic and Statistical Manual for Psychiatric Disorders [i.e., DSM-III (1980), DSM-III-R (1987), DSM-IV (1994)]. The subtypes of anxiety states included are panic disorder, agoraphobia, specific phobia, social phobia, generahzed anxiety/overanxious disorder, separation anxiety, and obsessive-compulsive disorder. 

DSM-IV specifies a total of 12 anxiety disorders, but starts by defining panic attacks. Panic attacks are defined separately but are not considered as a separate diagnostic category because they may occur in many of the other anxiety disorders. Likewise, agoraphobia and panic disorder are not considered as specific anxiety diagnoses but rather their combination. In the following, a description of the clinical presentation will be given ... 

Both acute and chronic anxiety can be treated with benzodiazepines, although it is anticipated that for most anxiety disorders counseling will also play an important role. Benzodiazepines employed in the treatment of anxiety should be used in the lowest effective dose for the shortest duration so that they will provide maximum benefit to the patient while minimizing the potential for adverse reactions. For most types of anxiety, none of the benzodiazepines is therapeutically superior to any other. Choice of a particular agent is usually made on the basis of pharmacokinetic (Table 30.2) considerations. A benzodiazepine with a long half-life should be considered if the anxiety is intense and sustained. A drug with a short half-life may have advantages when the anxiety is provoked by clearly defined circumsfances and is likely to be of short duration. 

Several controlled studies of IMI involved less homogeneous samples of anxious children. Neither IMI nor alprazolam (a BZ) was superior to placebo in an 8-week study of 24 children (ages 7-18 years) with school refusal, which included subjects with anxiety and depression (Bernstein et ah, 1990). A more recent placebo-controlled study of IMI -I- CBT for 47 adolescents (ages 12-18 years) with school refusal, anxiety, and/or depression was designed to address the limitations of previous studies of TCA treatment for pediatric anxiety disorders (Bernstein et ah, 2000). Accordingly, sample size was based on proposed power analysis IMI dose and serum level were monitored to ensure adequate exposure (mean IMI dose 180 mg/day mean serum IMI180 pg/L and mean IMI -I- DMI 250 pg/L at week 3 and week 8) and CBT was manual based and closely monitored. Fifty-four percent of subjects treated with IMI -I- CBT met remission criteria (defined as > 75% school attendance at the end of the study), compared to 17% of subjects treated with placebo -I- CBT. No between-group differences were noted... 

In the 20 century, many milestones were reached to establish psychology, psychiatry, and neuroscience as the formal practices that they are today. During this time, the study of anxiety disorders was developed into its current state. Notable events include Austrian-Hungarian endocrinologist Hans Selye s (Figure 1.3) pivotal work on the stress response in the 1930s. Selye did much to define how we think about stress and its effects on the body, and how the stress response can lead to illness. 

Before 1980, there weren t many references to childhood or adolescent anxiety in the psychiatric literature. But in 1980, three categories of anxiety disorder were defined, in the third edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-III). These categories were disorders that developed in infancy, childhood, or adolescence. DSM-III also recognized that other anxiety disorders, such as panic disorder, PTSD, and OCD, could also develop in childhood. 

This principle is not applicable in biological psychiatry. One can and should not simply discard the possibility that a biological variable observed in a psychotic condition is linked to a concurrent depression or that one found in depression is in fact related to a comorbid anxiety disorder. The hierarchical principle is a deus ex machina that resolves the problem of comorbidity only in appearance. Comorbidity in itself is merely a descriptive, not an explanatory, term. The multiplicity of psychiatric disorders, as they are presently defined, in so many patients permits a variety of explanations (Van Praag 1996], and thus the term comorbidity conceals more than it discloses. 

Another issue is that many primary care physicians have difficulty distinguishing between depressive and anxiety disorders. This has led to the impression that patients in a general medical setting are more likely to have an admixture of symptoms, rather than a clearly defined condition. That depressed patients have anxiety symptoms and anxiety-disordered patients have depressive symptoms, as assessed by the Flamilton scales, are used to support this clinical impression, which ignores the fact that these scales were developed to quantitate symptoms only after a definitive syndromic diagnosis had been made. 

The nosology of anxiety disorders has changed considerably over the past 40 years (141). Such disorders were not mentioned in the original DSM. In DSM-II, problems with anxiety were considered a subset of behavioral disorders and were restricted to overanxious and withdrawing reactions. The DSM-III defined three types of anxiety disorders in children and adolescents overanxious, avoidant, and separation disorder. The DSM-III also acknowledged that children and adolescents could meet adult criteria for simple phobias, panic disorder, posttraumatic stress disorder, and obsessive-compulsive disorder (OCD). In DSM-IV ( 45), generalized anxiety disorder (GAD) and social phobia (or social anxiety disorder with childhood onset) replaced overanxious disorder and avoidant disorder, respectively. 

Before outlining the main features of each anxiety disorder, it is necessary to define two terms panic attacks and anxiety symptoms. Panic attacks are very brief but extremely intense surges of anxiety. The major differences between a panic attack and more generalized anxiety symptoms are differences in the onset, duration, and intensity (see figure 7-A). Panic attacks often "come out of the blue" that is, they are not necessarily provoked by stress. They come on suddenly, are extremely intense, and last anywhere from 1 to 30 minutes and then subside. Tlie patient feels as if he or she will actually die or go crazy as we are not talking about uneasiness but fullblown panic. 

Generalized anxiety disorder (GAD) (6) is defined as excessive anxiety and worry occurring more days than not for a period of at least 6 months. The anxiety is accompanied by at least three of the following symptoms restlessness, fatigue, impaired concentration, irritability, muscle tension, and sleep disturbance. The anxiety is uncontrollable and causes clinically significant distress. GAD has a lifetime prevalence of 6-10% (7), and the NCS study (3) indicates a high comorbidity with other psychiatric disorders, especially depression and panic disorder. 

A word about prevalence mental illness is more common than many people imagine. The current prevalence estimates are that about half the U.S. population meets the criteria for at least one mental disorder during a lifetime, with about 25 percent of the population meeting the criteria for at least one mental disorder during any given year.1 Of these disorders, the most prevalent are apparently anxiety disorders, followed by mood disorders (for example, major depressive disorder), impulse-control disorders (for example, attention deficit hyperactivity disorder [ADHD]), and substance disorders (for example, alcohol abuse). In contrast, the prevalence of psychosis as I define it here is only 2—3 percent of the U.S. population, and the world prevalence is about the same. 

Paroxetine is a selective serotonin reuptake inhibitor that blocks reuptake of serotonin, enhancing serotonergic function. It is used to treat panic disorder or social anxiety disorder (except Pexeva), as defined in the DSM-IV major depressive disorder, as defined in DSM-111 (immediate release) orDSM-lV (controlled release). Immediate release only for obsessive-compulsive disorder (OCD) generalized anxiety disorder (GAD) (except Pexeva) posttraumatic stress disorder (PTSD), as defined in the DSM-IV (except Pexeva). 

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