Panic Disorder - Types Of Anxiety Disorders: Mental Health

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Panic disorder

The experience: A woman, age 52, is walking down the street on her way to work when she's suddenly stricken with terror. She trembles, becomes hot and sweaty, has chest pains, and feels like she can't breathe. The attack passes after about 10 minutes, but the woman has had four similar spells in the past six months. Sometimes the attacks occur in stressful situations, but often they begin for no apparent reason. One even wakes her in the middle of the night. She's increasingly worried that she'll have another attack, so she avoids situations that she fears might trigger them. Eventually, she seeks help from a psychiatrist, who diagnoses panic disorder.

Symptoms: Panic disorder is marked by panic attacks that strike suddenly and repeatedly without warning. These attacks often occur for no apparent reason. In addition, they are followed by at least a month of anticipatory anxiety — intense worry about having another attack or about the consequences of an attack (for example, losing control or having a heart attack). Often those affected will become anxious about having panic attacks in certain public places or situations where they have had them before. This causes them to deliberately avoid those situations or places, a behavior known as phobic avoidance. About one-third of those with panic disorder develop agoraphobia, an extreme form of public avoidance. Many people with agoraphobia grow so afraid of being out in public that they become housebound.

Two-thirds of those with panic disorder also have other psychiatric disorders. About half experience an episode of major depression, which may come either before or after the first panic attack. Research suggests that having panic disorder along with a mood disorder, personality disorder, or alcoholism may increase the risk of suicide.

Cause: Panic disorder has both biological and psychological causes. Because the disorder runs in families, researchers are examining several genes that might contribute to its development.

Some experiments suggest that panic disorder is the result of a hypersensitivity to brain changes that transmit warning messages. In these experiments, panic attacks were induced in susceptible people with high doses of a stimulant like caffeine, which activates the sympathetic nervous system (a part of the autonomic nervous system). The sympathetic nervous system transmits signals to all parts of the body to prepare it for physical action, known as the "fight-or-flight" response. It speeds heart rate, narrows blood vessels, and raises blood pressure.

In most people, large amounts of caffeine produce some of the physical symptoms of panic, such as increased heart rate. But among individuals with panic disorder, too much caffeine can trigger a full-blown panic attack. In similar experiments, deep breathing caused by strenuous exercise or inhaling air with a high concentration of carbon dioxide provoked attacks in people with panic disorder. The brain seemingly misinterprets deep, rapid breathing as a sign that the body is in trouble and triggers a stress response.

One theory is that faulty brain receptors don't respond to naturally occurring benzodiazepines, the body's anxiety-reducing chemicals. Some research suggests that panic disorder may involve an abnormality in the limbic system. Brain images of people having a panic attack show abnormal activity around the hippocampus, a key element in the limbic system.

Psychological factors are also important because a major symptom is the fear of having more panic attacks. Individuals become conditioned to anticipate the attacks. This anticipation produces anxious thoughts, which may induce panic attacks. Researchers think the amygdala may play a role in anticipatory anxiety and are studying this part of the brain, where fear conditioning and other forms of unconscious emotional learning occur.

Prevalence: Panic disorder affects about 3% of the population.

Who's at risk: Women are twice as likely to suffer from panic disorder as men, and they are three times as likely to have agoraphobia. Someone who has a close relative with panic disorder has a 10%–20% chance of developing the condition, while someone whose identical twin has panic disorder has a risk of 30%. The disorder usually begins during late adolescence or early adulthood.

Other factors predispose people to panic disorder. One is anxiety sensitivity, a personality trait that can be identified in children as young as age six. People with anxiety sensitivity believe that the physical sensations associated with anxiety, such as dizziness and shortness of breath, are life-threatening. There also seems to be a link between high blood pressure and panic disorder. In a study published in the American Journal of Medicine, more than a third of people with high blood pressure also had panic disorder, a rate that's far higher than that of the general population. The reason for the association isn't known. It may be that adrenaline surges during panic attacks might raise a person's blood pressure or that the two conditions have the same underlying cause.

Effective treatments: Selective serotonin reuptake inhibitors (SSRIs) are first-line treatments. All SSRIs are comparable in effectiveness. Because these antidepressants can take three to eight weeks to work, they are often combined with a short course of one of the benzodiazepines, anti-anxiety drugs that work quickly to relieve panic disorder. SSRIs are the first choice because for many people they have fewer and less severe side effects than other medications. Tricyclic antidepressants or monoamine oxidase (MAO) inhibitors are used when SSRIs don't work (see "Medications for anxiety disorders").

Cognitive behavioral therapy can be helpful for those who fear future panic attacks or who avoid situations or places that they think may trigger an attack. The specific combination of treatments will depend, to a large degree, on the individual's other mental health conditions, if any. Studies show that medication, cognitive behavioral therapy, or a combination of both help 70%–90% of people with panic disorder.

Last updated:	September 05, 2008