Causes of Anxiety Disorders
The causes of anxiety disorders are not fully known, but the following may be involved:
- Genetic factors (including a family history of an anxiety disorder);
- Environment (such as experiencing a traumatic event or stress);
- Psychological makeup; and
- A physical condition.
An anxiety disorder can be triggered by environmental stresses, such as the breakup of a significant relationship or exposure to a life-threatening disaster.
When an individual’s response to stresses is inappropriate or a person is overwhelmed by events, an anxiety disorder can arise. For example, some individuals find speaking before a group exhilarating. But others dread it, becoming anxious with symptoms such as sweating, fear, a rapid heart rate, and tremor. Such individuals may avoid speaking even in a small group.
Anxiety tends to run in families. Medical professionals think some of this tendency may be inherited, but some is probably learned by living with anxious individuals.
Anxiety caused by a Physical Disorder to Drug
Anxiety can also be caused by a general medical disorder or the use or discontinuation (withdrawal) of a drug. General medical disorders that can cause anxiety include the following:
- Heart disorders, such as heart failure and abnormal heart rhythms (arrhythmias);
- Hormonal (endocrine) disorders, such as an overactive adrenal gland (hyperadrenocorticism) or thyroid gland (hyperthyroidism) or a hormone-secreting tumor called a pheochromocytoma; and
- Lung (respiratory) disorders, such as asthma and chronic obstructive pulmonary disease (COPD).
Even fever can cause anxiety.
Anxiety may occur in dying individuals as a result of fear of death, pain, and difficulty breathing.
Drugs that can trigger anxiety include the following:
- Stimulants (such as amphetamines);
- Many prescription drugs, such as corticosteroids; and
- Some over-the-counter weight-loss products, such as those containing the herbal product guarana, caffeine, or both.
Withdrawal from alcohol or sedatives, such as benzodiazepines (used to treat anxiety disorders), can cause anxiety and other symptoms, such as insomnia and restlessness.
Causes of Trauma- and Stress-Related Disorders
Trauma- and stress-related disorders result from exposure to a traumatic or stressful event.
Specific disorders include acute stress disorder and post-traumatic stress disorder. These disorders cause similar symptoms but differ in how long they last.