Considered the most common mental illnesses, anxiety disorders affect an estimated 18 percent of the adult population in a given year, or 40 million Americans.
Anxiety disorders include obsessive-compulsive disorder (OCD); panic disorder; phobias, such as acrophobia, or fear of heights and; agoraphobia, or fear of open spaces; social anxiety disorder; generalized anxiety disorder; and post-traumatic stress disorder (PTSD). These disorders can be crippling, to the point of keeping people completely housebound. What’s more, anxiety disorders often occur with depression, and individuals doubly afflicted are at a high risk of suicide.
People with OCD become trapped, often for many years, in repetitive thoughts and behaviors, which they recognize as groundless but cannot stop. Such behavior includes repeatedly washing hands or checking that doors are locked or stoves turned off. The illness is estimated to affect 2.2 million American adults annually. One-third of adults develop their symptoms as children.
Neuroscientists think that environmental factors and genetics probably play a role in the development of the disorder. Positron emission tomography (PET) scans reveal abnormalities in both cortical and deep areas of the brain, implicating central nervous system changes in individuals with OCD.
OCD is not limited to people either. Scientists have recently discovered that certain breeds of large dogs develop acral lick syndrome, severely sore paws from compulsive licking. These dogs respond to the serotonergic antidepressant clomipramine, which was the first effective treatment developed for people with OCD. This and other serotonergic antidepressants, as well as selective serotonin reuptake inhibitors (SSRIs) such as sertraline and paroxetine, are effective in treating OCD. A specialized type of behavioral intervention, called exposure and response prevention, also is effective in many patients.
With a lifetime prevalence rate of 4.7 percent in the United States, panic disorder usually starts unexpectedly. Patients experience an overwhelming sense of impending doom, accompanied by sweating, weakness, dizziness, and shortness of breath.
With repeated attacks, patients may develop anxiety in anticipation of another attack. As a result, people may avoid public settings where attacks might occur. If these individuals are untreated, they may develop agoraphobia and become virtually housebound. Antidepressants, including SSRIs, are effective, as is cognitive behavioral therapy.
Phobia is an intense, irrational fear of a particular object or situation. Individuals can develop phobias of almost anything, including dogs, dating, blood, snakes, spiders, or driving over bridges. Exposure to the feared object or situation can trigger an extreme fear reaction that may include a pounding heart, shortness of breath, and sweating. Cognitive behavioral therapy is an effective treatment. It is likely that panic disorders and phobias have similar neurochemical underpinnings that emerge as the result of a particular “stressor.”