Anxiety sensitivity

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Anxiety sensitivity

“The thing I fear most is fear,” wrote the sixteenth century philosophical essayist Michel de Montaigne. He might have been referring to anxiety sensitivity, a phenomenon first described by psychologists in the 1980s and since then increasingly used in the explanation and treatment of psychiatric disorders.

Anxiety sensitivity is a tendency to misinterpret the sensations that accompany anxiety — irregular breathing, heart palpitations, trembling, flushing, sweating, stomach rumbling — as indications of imminent physical danger or serious illness (“I’m going to have a heart attack;” or “I’m going to faint”), loss of control (“I can’t concentrate — I’m going crazy!”), or humiliating social rejection (“Everyone will notice that I’m trembling”). Standard questionnaires have been developed to measure the phenomenon. The most widely used is the Anxiety Sensitivity Index, which asks people to affirm or deny statements like “Unusual body sensations scare me.”

A person with high anxiety sensitivity may be low in actual anxiety, and vice versa. Still, anxiety sensitivity influences the development of anxiety disorders, as well as hypochondriacal fears and depression. Its relationship to panic attacks is especially intimate; some experts regard panic disorder as a result of anxiety sensitivity.

Say that, driving over a bridge on a windy day, you suddenly are struck by the thought that the bridge might collapse. You feel tension in your chest, your heart begins to pound, and if your anxiety sensitivity is high, you think you may be having a heart attack. Physical symptoms and the anticipation of disaster reinforce each other. You become still more anxious, your heart beats faster, and the panic mounts.

Panic disorder, by definition, involves not only panic attacks but a dread of panic attacks (anticipatory anxiety) that causes a tendency to avoid an increasing number of people, places, and situations that might provoke an attack (agoraphobia). People with high anxiety sensitivity are naturally more likely to fear panic attacks. They are also more likely to show symptoms of panic in response to hyperventilation or inhalation of carbon dioxide (which mimics oxygen shortage), even if they have never had a panic attack. So they are especially susceptible to both anticipatory anxiety and agoraphobia.

The same pattern applies to other physical symptoms. For example, studies suggest that people with high anxiety sensitivity are more afraid of pain and more likely to seek unnecessary treatment for minor pain symptoms — a form of hypochondria.

Like chronic anxiety, anxiety sensitivity seems to run in families, possibly for genetic reasons and possibly because parents provide a model for their children. But some studies suggest that the family-related effect does not appear in childhood. It’s not clear whether the children (as opposed to adult relatives) of a person high in anxiety sensitivity will also be high in anxiety sensitivity.

Because anxiety sensitivity raises the risk for so many symptoms and disorders, it is a potential target for therapy. Clinicians have incorporated it into standard cognitive and behavioral treatments for panic disorder and post-traumatic stress. In a technique known as interoceptive exposure therapy, for example, the therapist deliberately induces the symptoms that patients with panic disorder fear most by having them spin in a chair, hyperventilate (breathe deeply and rapidly), or run upstairs repeatedly. Patients can rate experiences as more or less anxiety-provoking, identify the sensations they have been misinterpreting, and understand why their fears are unrealistic. They also practice anxiety-provoking exercises in homework assignments until the fear of fear loses its grip — a form of systematic desensitization.

Success may even come more easily. In one study, therapists were able to reduce the number of panic attacks suffered by patients with high anxiety sensitivity by a diagnostic interview in which they made the symptoms more tolerable simply by naming and describing them.

In fact, it’s possible that most cognitive behavioral techniques used to treat panic disorder work largely by their effect on the underlying anxiety sensitivity. There is evidence that patients successfully treated for panic disorder are more likely to relapse if they still have high anxiety sensitivity after treatment. Lowering anxiety sensitivity might also prevent panic attacks in certain people who are at high risk because of depression or other psychiatric disorders.

The drugs used to treat anxiety disorders may also affect anxiety sensitivity. Researchers at Harvard treating panic disorder patients with three different drugs or combinations of drugs, found that lowered anxiety sensitivity was the best measure of improvement in the symptoms. But some suspect that drugs too often leave underlying anxiety sensitivity intact while suppressing anxiety itself.

The effect of medication is only one of the topics that needs more study. Another is how anxiety sensitivity develops; maybe long-term research on children growing up will tell. Lowering anxiety sensitivity to prevent panic disorder and hypochondria has also been more discussed than practiced. But whatever direction future exploration takes, the fear of fear itself has become a permanent subject of clinical investigation.

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Last updated:	August 21, 2006