Many patients experience a constant uneasiness that the spells may reoccur, especially in public; hence the patient may be fearful of leaving home lest help not be available should an attack occur (agoraphobia). Except in minor details, it is notable that the attacks are alike in any one individual. Between attacks, most patients feel relatively well but many complain of the symptoms of anxiety and asthenia in lesser but persistent fashion.
Hyperventilation is a special, although not invariable, feature of the anxiety attack. Hyperventilation itself, by reducing the Pco2, will cause giddiness, paresthesias of the fingers, tongue, and lips, and, at times, frank tetany. However, contrary to what is stated in some textbooks, in only a minority of patients does a 3-min period of deep breathing reproduce the symptoms of an anxiety or panic attack. Nonetheless, this maneuver may be used to assist the patient in describing certain aspects of an attack.
Attacks in minor form, without the full force of the physical accompaniments may occur at infrequent intervals or several times a day. Much to the patient’s surprise, they usually occur in situations where there are no easily recognizable sources of fear, as when the patient is sitting quietly at home or has just awakened from sleep. In other instances, a trying or upsetting experience induces an attack, which is nonetheless excessive for the condition that provoked it. In some patients, attacks are brought on consistently by confinement to a closed space (claustrophobia)—an elevator, for example—or by crowded surroundings, as in a church, restaurant, or theater. An anxiety state frequently follows an accident and then may, according to Modlin, be a source of ongoing disability, a condition more akin to posttraumatic stress disorder. Similar spells of anxiety are also a prominent feature of the postconcussive and posttraumatic stress syndromes.
From the patient’s life history, 2 patterns of anxiety neurosis are discernible. In one, there is a nearly lifelong history of poor exercise tolerance, little stamina, and inability to do heavy physical work or participate in vigorous sports, tenseness, nervousness, and intolerance of crowds, that is, what had in the past been called neurasthenia (or nervous exhaustion), named by the neurologist George Beard in 1869 and renamed innumerable times by others as a result of its widespread applicability in all branches of medicine. When these symptoms arose during military service, they were designated, since the American Civil War as neurocirculatory asthenia, “irritable heart,” or “soldier’s heart.”
The course of anxiety traits is variable. A 20-year followup study by Wheeler and associates showed that symptoms were still present in 88 percent but persisted in being moderately or severely disabling in only 15 percent. Most affected patients were able to work and to enjoy a reasonably normal family and social life. Their only liability to further psychiatric illness was to later anxious depression, whereas so-called psychosomatic illnesses and other psychiatric illnesses did not occur more frequently than in the general population. Those with uncomplicated anxiety neurosis rarely commit suicide.
Anxiety disorder has been attributed to a genetic abnormality, to a “constitutional weakness” of the nervous system, to social and psychologic factors, and to physiologic and biochemical derangements; but none of these factors provides a completely satisfactory explanation of the primary problem.