Anxiety disorders are a group of mental disorders characterized by significant feelings of anxiety and fear. Anxiety is a worry about future events and fear is a reaction to current events. These feelings may cause physical symptoms, such as a fast heart rate and shakiness. There are a number of anxiety disorders: including generalized anxiety disorder, specific phobia, social anxiety disorder, separation anxiety disorder, agoraphobia, panic disorder, and selective mutism. The disorder differs by what results in the symptoms. People often have more than one anxiety disorder. The cause of anxiety disorders is a combination of genetic and environmental factors. Risk factors include a history of child abuse, family history of mental disorders, and poverty. Anxiety disorders often occur with other mental disorders, particularly major depressive disorder, personality disorder, and substance use disorder. To be diagnosed symptoms typically need to be present for at least six months, be more than would be expected for the situation, and decrease functioning. Other problems that may result in similar symptoms including hyperthyroidism; heart disease; caffeine, alcohol, or cannabis use; and withdrawal from certain drugs, among others. Without treatment, anxiety disorders tend to remain. Treatment may include lifestyle changes, counselling, and medications. Counselling is typically with a type of cognitive behavioral therapy. Medications, such as antidepressants, benzodiazepines, or beta blockers, may improve symptoms. About 12% of people are affected by an anxiety disorder in a given year and between 5-30% are affected at some point in their life. They occur about twice as often in females as males, and generally begin before the age of 25. The most common are specific phobia which affects nearly 12% and social anxiety disorder which affects 10% at some point in their life. They affect those between the ages of 15 and 35 the most and become less common after the age of 55. Rates appear to be higher in the United States and Europe.

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