Generalized anxiety disorder overview

# Overview
Generalized anxiety disorder (GAD) is an anxiety disorder that is characterized by excessive, uncontrollable and often irrational worry about everyday things, which is disproportionate to the actual source of worry.  This excessive worry often interferes with daily functioning, as individuals suffering from GAD typically catastrophize, anticipate disaster, and are overly concerned about everyday matters such as health issues, money, family problems, or work difficulties. They often exhibit a variety of physical symptoms, including fatigue, headaches, muscle tension, muscle aches, difficulty swallowing, trembling, twitching, irritability, sweating, and hot flashes. These symptoms must be consistent and on-going, persisting at least 6 months, for a formal diagnosis of GAD to be introduced.   Approximately 6.8 million American adults experience GAD, affecting about twice as many women as men.

# Historical Perspective
Generalized anxiety disorder was first recognized as a symptom by Sigmund Freud. In 1980, 'The American Psychiatric Association' introduced GAD as a diagnosis in the DSM-III.

# Classification
Generalized anxiety disorder falls under the category of anxiety disorder.

# Pathophysiology
Generalized anxiety disorder has been linked to the disrupted functional connectivity of the amygdala and its processing of fear and anxiety.

# Differentiating Generalized anxiety disorder from other Disorders
The differential diagnosis in generalized anxiety disorder is similar to that of panic disorder. It is important to rule out drug-induced conditions. The mental status examination should take in consideration the possibility of schizophrenia, obsessive-compulsive disorder, major depressive disorder, and both specific and social phobias.

# Epidemiology and Demographics
Generalized anxiety disorder is relatively common and has a lifetime prevalence of about 4-7% in the general population. It is more common in women, and can develop in any age although it more commonly occurs in the third and fourth decade of life. Approximately one quarter of the patients with generalized anxiety disorder, will develop panic disorder.

# Risk Factors
Risk factors for developing generalized anxiety disorder include family history, early adulthood, and a recent life stressor.

# History and Symptoms
The criteria for generalized anxiety disorder include at least 6 months of excessive anxiety or worry, about a number of situations, which is difficult to control. The worry may also be associated with three of the following symptoms; restlessness. fatigue, irritability, muscle tension, poor sleep, and difficulty concentrating. There are several disorders that have a tendency to co-occur with generalized anxiety disorder. These include; major depressive disorder, panic disorder, social phobia, agoraphobia, substance abuse, irritable bowel syndrome and sleep disorders.

# Natural history, Complications, and Prognosis
In the National Comorbidity Survey (2005), 58% of patients diagnosed with major depression were found to have an anxiety disorder; among these patients, the rate of comorbidity with GAD was 17.2%, and with panic disorder, 9.9%.

# Diagnostic Criteria
The criteria for generalized anxiety disorder include at least 6 months of excessive anxiety or worry, about a number of situations, which is difficult to control. The worry may also be associated with three of the following symptoms; restlessness. fatigue, irritability, muscle tension, poor sleep, and difficulty concentrating.

# History and Symptoms
There are several disorders that have a tendency to co-occur with generalized anxiety disorder. These include; major depressive disorder, panic disorder, social phobia, agoraphobia, substance abuse, irritable bowel syndrome and sleep disorders.

## Laboratory Findings
There are no laboratory findings associated with generalized anxiety disorder.

## Other Imaging Findings
There are no other imaging findings associated with generalized anxiety disorder.

## Other Diagnostic Studies
There are no other diagnostic studies associated with generalized anxiety disorder.

# Medical Therapy
There are a variety of medications which can be used to treat generalized anxiety disorder, and they generally work well particularly in conjunction with psychotherapy. The first line treatments are the SSRI class of antidepressants such as fluoxetine, paroxetine, and escitalopram. Other antidepressants such as imipramine, venlafaxine, and buspirone may also be effective. Benzodiazepines provide quick, effective relief from anxiety, however must be prescribed with caution due to a high risk of abuse and dependence.

# Psychotherapy
A psychological method of treatment for GAD is cognitive behavioral therapy (CBT), which involves a therapist working with the patient to understand how thoughts and feelings influence behavior. The goal of the therapy is to change negative thought patterns that lead to the patient's anxiety, replacing them with positive, more realistic ones.  Elements of the therapy include exposure strategies to allow the patient to gradually confront their anxieties and feel more comfortable in anxiety-provoking situations, as well as to practice the skills they have learned.  CBT can be used alone or in conjunction with medication.
Neuroscience education may reduce catastrophizing among patients with chronic musculoskeletal pain.

# Brain Stimulation Therapy
There is no FDA approved brain stimulation therapy available for generalized anxiety disorder.