The causes of anxiety disorder are unknown. Research indicates that areas of the brain that control the fear response may be involved. Anxiety disorder seems to run in families. This suggests that a combination of genetic and environmental factors may contribute to the development of the disorder. Brain chemistry is also being studied as a possible cause. Brain chemicals that may be involved include serotonin, dopamine, and norepinephrine.
Anxiety disorder often occurs with other mental and physical conditions, such as substance abuse and depression. Many people try to ease the symptoms of anxiety with alcohol and other drugs. The relief these drugs may provide is temporary, however. These drugs, as well as caffeine and nicotine, can make an anxiety disorder worse.
Much research is being done to learn about the causes of anxiety disorders. Scientists believe that a combination of factors is involved, including genes, pollution, stress, and diet.
Studies of twins suggest that genetics may play a role. Another mental health condition, post-traumatic stress disorder (PTSD), is the result of trauma. But some people exposed to trauma develop PTSD while others do not. This fact points to a combination of genetics and environment.
Certain parts of the brain are also being studied. The amygdala is a small structure deep inside the brain that stores emotional memories. It alerts the rest of the brain when there is danger, and can trigger a fear and anxiety response. It seems to play a part in anxiety disorders that involve fear of specific things, such as cats, bees, or drowning.
The hippocampus is a region of the brain involved in storing memories of threatening events. It appears to be smaller in people who have experienced child abuse or served in combat. It may play a role in the development of anxiety disorders.
Though the exact cause of anxiety disorder is not clear, risk factors have been identified. Conditions that are frequently associated with anxiety disorder include:
- irritable bowel syndrome
- substance abuse
- another anxiety disorder
Other factors that can increase your risk of developing an anxiety disorder are described below.
Everyone encounters stress. Excessive or unresolved stress can increase your chances of developing chronic anxiety.
If someone in your family, especially a parent, has anxiety, you have a greater risk of developing generalized anxiety disorder.
Some people are more prone to anxiety. Busy, high-strung people (“type A” personalities) have greater risk of developing anxiety and stress-related disorders.
Severe trauma, such as child abuse or military combat, increases your risk of developing anxiety. This can include being the victim of trauma, being close to someone who is the victim of trauma, or witnessing something traumatic.
Women are twice as likely as men to have generalized anxiety disorder and other related conditions.
Some medical conditions and medications can produce anxiety and symptoms similar to anxiety, but this is not a true anxiety disorder. In these cases, treating the condition or discontinuing the medication will usually relieve the symptoms.