Articles from prior issues of The Advocate

January/February, 1996

Panic Disorders, Part II
Continued from the September/October Issue

THE DIAGNOSIS OF PANIC DISORDER

Presently, there is no practical and reliable laboratory test for identifying or ruling out panic disorder in the clinical setting. Thus, aside from tests to rule out other conditions that can mimic the manifestations of panic, the diagnosis is based entirely on the history and physical examination.

THE DIAGNOSTIC CRITERIA

A panic attack is a discrete period of intense fear that arises suddenly and is

1.Not expected (ie, not a phobic response triggered by objects or situations known to cause anxiety);

2.Not related to situations in which the patient was the focus of other people’s attention (ie,not a social phobia); and

3. Not attributable to any somatic cause (eg, stimulant abuse or hyperthyroidism-see Differential Diagnosis, next page). To fulfill the DSM-III-R criteria for a diagnosis of panic disorder, the patient must have had at least four panic attacks within a 4-week period or one or more attacks that were followed by at least a month of persistent anxiety about having another. One or more of the attacks must have been accompanied by at least four characteristic signs or symptoms arising suddenly and intensifying rapidly. An episode accompanied by less than four symptoms from the list is called a “limited-symptom attack.” Most panic-disorder patients exceed the minimum criteria. At the time they seek help, many patients are suffering several attacks per week or even several per day, often with consistent patterns of physical symptoms. To be diagnosed as having panic disorder with agoraphobia, the patient must meet the criteria for panic disorder and must express a fear of being in places or situations from which escape would be difficult or embarrassing or where help would be unavailable if a panic attack were to occur. Because of this fear, patients either restrict travel or seek companions when traveling; otherwise, they suffer severe anxiety in agoraphobia-provoking settings.

THE DIFFERENTIAL DIAGNOSIS

Panic attacks were once considered strictly a psychologic phenomenon brought on by unresolved emotional problems. Recognition of an organic basis for panic disorder stems mainly from discoveries made during the 1960s. In particular, researchers found that an infusion of sodium lactate could induce acute panic attacks in patients with a history of such attacks but not in patients with generalized anxiety or in normal subjects. On the basis of these findings, it has become clear that panic disorder is not merely a variant form of phobia or generalized anxiety disorder. Because there is currently no pathognomonic finding or laboratory test that can positively establish the existence of panic disorder, the diagnosis is made only after excluding other conditions that can cause panic-like symptoms. Even then, the clinical picture may be clouded by the presence of comorbid physical or psychiatric disorders, some of which may represent direct complications of untreated panic disorder. In physically healthy patients who are later diagnosed as having panic disorder, the most common symptoms experienced during acute attacks involve the cardiovascular system, eg, chest pain and palpitations. Indeed, one of the names by which panic disorder has been called is “anxious heart syndrome.” If the examining physician does not consider the possibility of panic disorder when routine investigations reveal no cardiac pathology, the patient who reports cardiovascular symptoms may be subjected to needless, expensive, and potentially hazardous invasive testing. On the other hand, true organic disease may coexist with panic disorder. The classic example is mitral valve prolapse syndrome (MVPS). The relationship between these conditions may be summarized as follows:

1.MVPS is more common in panic-disorder patients than in the general population, yet panic disorder is not more common is MVPS patients than in the general population.

2.There may be a subset of panic-disorder patients with structurally abnormal mitral valves that give way under the increased hemodynamic stress related to excessive sympathetic outflow to the heart. This possibility may, in part, explain the first point and is consistent with the fact that MVPS is also more common in patients with hyperdynamic circulation secondary to other conditions, such as hyperthyroidism.

3.Therapeutic outcome in panic disorder shows no correlation to the presence or absence of MVPS. Among the other medical conditions that are often comorbid with panic disorder, hypertension and peptic ulcer disease are the most prominent. Among the psychiatric problems that may accompany panic disorder (aside from such recognized complications as agoraphobia, depression, and substance abuse), focal phobias, hypochondriasis and disturbances in eating and sleeping patterns have been reported.

NEUROCHEMICAL AND PSYCHOSOCIAL FACTORS

An acute panic attack involves more than just the cognitive and emotional sensation of fear. The patient is also aware of a variety of unpleasant physical symptoms, which are often associated with measurable changes in physiologic performance. Some of these changes, in turn, are directly mediated by changes in autonomic output from the central nervous system. Yet panic disorder is not simply a genetic abnormality in neurochemistry. A higher incidence of panic disorder exists among family members of patients, and recent research is revealing some patterns of inheritance. However, psychosocial factors can affect the expression and severity of panic attacks. For example,in the laboratory, patients in whom panic attacks have been chemically induced often report less severe symptoms when a trusted person, such as a physician, is present. Pharmacologic intervention in panic disorder is aimed at the neurochemical processes, but it does not address the psychosocial context of a patient’s condition. However, once the severe symptoms are averted, the patient can begin to resume normal activities. Counseling can also help the patient address relevant psychosocial problems.

DIAGNOSTIC CRITERIA FOR PANIC DISORDER

A panic attack is a period of intense fear not due to focal or social phobia and not attributable to any specific organic cause. The patient has at least four such attacks within four weeks or at least one attack followed by at least one month of fear of having another. Some or all attacks are accompanied by at least four of the following manifestations, each arising suddenly and intensifying quickly, all within the first ten minutes:

shortness of breath or smothering sensation

dizziness, unsteady feelings, or faintness

palpitations or accelerated heart rate

trembling or shaking

choking

nausea or abdominal distress

numbness or tingling sensations

depersonalization (sense of loss of one’s own identity or existence) or derealization (altered perception-familiar things looking strange, unreal, or two-dimensional)

sweating, flushes or chills

chest pain or discomfort

fear of dying

fear of going crazy or of doing something uncontrolled