The anxiety disorders described on this site derive from an earlier classification of anxiety disorders presented in DSM-IIIR (Diagnostic and Statistical Manual of Mental Disorders—Third Edition, Revised). The newer DSM-IV classification, which appeared in May 1994, added the following four disorders.
Acute Stress Disorder
Like post-traumatic stress disorder, acute stress disorder involves developing anxiety and other disabling symptoms after exposure to a traumatic event. The principal distinction is that the symptoms subside in less than one month; if the symptoms last beyond one month, the diagnosis is changed from acute stress disorder to post-traumatic stress disorder. As with post-traumatic stress disorder, the initial trauma involves exposure to an event that carries the threat of death or serious injury (for example, military combat, violent personal assault, sexual assault, natural or manmade disasters, car accidents, or being diagnosed with a life-threatening illness). Either during or after the traumatic incident, you have symptoms such as numbness, detachment, or feelings of unreality or depersonalization. Later you tend to avoid anything that reminds you of the incident, and have persistent symptoms of anxiety (difficulty sleeping, irritability, poor concentration, exaggerated startle response, restlessness). This disturbance typically interferes with your work and your significant relationships but, as indicated, lasts no longer than four weeks following the traumatic event.
Agoraphobia Without a History of Panic Disorder
This particular anxiety disorder has all of the same features as agoraphobia—such as avoidance of a variety of situations—but there is no history of having had full-blown panic attacks. Instead, the focus of your fear is on one or two symptoms among all those listed for panic disorder. For example, you might be afraid only of having heart palpitations if you venture too far from home or go to a crowded public place. Sometimes the fear is of an incapacitating symptom not on the list of panic attack symptoms. For example, you might be afraid to drive long distances and/or to be far from a town because of a fear of losing bladder control or having a bout of diarrhea.
Only a small percentage of people with agoraphobia do not have a history of panic disorder (estimates range from 5 to 15 percent). Treatment emphasizes relaxation, cognitive therapy, and in vivo exposure.
Anxiety Disorder Due to a General Medical Condition
This diagnostic category is reserved for situations in which significant anxiety (either in the form of panic attacks or generalized anxiety) is a direct physiological effect of a specific medical condition. Numerous types of medical conditions can cause anxiety, including endocrine conditions (hyper- and hypothyroidism, hypoglycemia), cardiovascular conditions (congestive heart failure, pulmonary embolism), metabolic conditions (vitamin B12 deficiency or iron deficiency), and neurological conditions (vestibular problems, encephalitis).
Substance-Induced Anxiety Disorder
This category is used when panic attacks or generalized anxiety is determined to be the direct physiological effect of a substance, whether a drug of abuse, a medication, or toxin exposure. The anxiety may be a result either of exposure to the substance or withdrawal from it. For example, if you had no previous history of an anxiety disorder, then suddenly developed panic attacks as a result of withdrawing too quickly from a medication, you would receive this diagnosis.
