The disorder is characterised by excessive bouts of anxiety and worry. The clinical presentation of anxiety disorders includes all or some of the following symptoms on a general scale [8]:

• Restlessness or feeling keyed-up or on edge
• Being fatigued quickly
• Difficulty in concentration and the mind going blank
• Muscle tension
• Irritability
• Sleep disturbance
• Suicidal ideation is not a diagnostic feature but it is associated with anxiety disorder.

When the chances of anxiety disorder being caused by a medical disorder is low or not presented clearly, initial laboratory studies to be carried out include:

• Complete blood cell count
• Urine drug screen
• Chemistry profile
• Urinalysis 
• Thyroid function tests

To further exclude medical disorders, the following studies may be carried out:

• Electroencephalography, lumbar puncture, and head/brain imaging
• Tests for infection
• Thyroid function
• Arterial blood gas analysis
• Electrolyte analysis
• Chest radiography
• Electrocardiography

Treatment of anxiety disorders is made up of a combination of pharmacotherapy and psychotherapy. The drugs of choice are antidepressant agents [9]. The preferred type these days are the newer agents as they have a much safer adverse effect profile as well as a higher ease of use than selective serotonin reuptake inhibitors (SSRIs) and other older tricyclic antidepressants (TCAs).

The outcome of treatment is determined by several factors which include the following:

• Severity of diagnosis
• Level of functioning prior to onset of symptoms
• Degree of motivation for treatment
• Level of support (eg, family, friends, work, school)
• Ability to comply with medication and/or psychotherapeutic regimen

This disorder has a high rate of comorbidity with the abuse of drugs and alcohol as well as major depression. Therefore the increased morbidity and mortality that is common with anxiety disorders is related to this high rate of comorbidity [6]. Anxiety disorders may also contribute to morbidity and mortality via direct stimulation such as hypertension or cardiac arrhythmia or neuroimmune and neuroendocrine mechanisms.

Considerable evidences show that some variants of anxiety disorder leads to significant functional impairment as well as a decreased quality of life.

Severe cases of anxiety disorders may be further complicated by suicide, with or without secondary mood disorders such as depression [7].

A known or unrecognised medical condition is often the first consideration when looking at the causes of anxiety disorders [3]. Most of the time however, anxiety disorder arises as a result of over-the-counter medication or substance abuse. Unfortunately, this is missed most of the time in diagnosis.

Genetic factors also significantly impact risk for anxiety disorders as is the case with environmental factors like early childhood trauma. The arguments on how genes and environment contributes to risk of anxiety disorder has led to the understanding that while some individuals are resilient to stress others are vulnerable to it and this leads to a form of anxiety disorder.

Over 273 million or 4.5% of the world population had an anxiety disorder according to 2010 statistics. The condition is also seen most in females (5.2%) as against (2.8%) in males [4].

In Europe, Africa and Asia, the lifetime rates of anxiety disorders are between 9 and 16%. The yearly rates are also between 4 and 7%. In the U.S between 11 and 18% of adults develop the condition in a year and the lifetime prevalence is 29%.

The major mediators of the symptoms synonymous with anxiety disorders in the central nervous system (CNS) include gamma-aminobutyric acid (GABA), dopamine, serotonin and norepinephrine. Other peptides and neurotransmitters like the corticotropin-releasing factor may also be involved [5]. The autonomic nervous system, with emphasis on the sympathetic nervous system, mediates a good number of the symptoms.

It has been demonstrated with the aid of positron emission tomography (PET) that there is often increased flow in the right parahippocampal area as well as a reduction in serotonin type 1A receptor binding in the anterior and posterior cingulate and raphe of people with anxiety disorders (especially panic disorders).

There are no guidelines for the prevention of anxiety disorder.

Anxiety disorders refer to a group of mental disorders that trigger fear and anxiety. The anxiety brings about worries about future events and fear brings about reactions (often inexplicable and exaggerated to onlookers) to current events [1]. A combination of these disorders can bring about physical symptoms like tachycardia and shakiness.

There are different forms of anxiety disorders with each of them varying in seriousness but they have identical presentations. The different types of anxiety disorders include panic disorder (most severe of the group), phobic disorder and generalised anxiety disorder.

Anxiety disorders are often genetic but they may also arise due to use of certain drugs like alcohol and caffeine. It may also be seen following withdrawal from certain drugs. In some cases, anxiety disorders occur in tandem with bipolar disorders, eating disorders and major depressive disorders [2].

With anxiety disorders, the emotions presented may range from simple nervousness to full blown bouts of terror. There are other psychiatric problems that show the same symptoms as anxiety disorders. Hyperthyroidism is the prime example.

There is nothing wrong with the occasional feeling of anxiety especially when your life is generally stressful. However, you are dealing with an anxiety disorder when it becomes severe and impedes your day to day activities.

Anxiety disorders can be developed as a child or as an adult and there are various forms of anxiety disorder that are slightly different. They often bring about similar symptoms and it takes the help of a professional to determine what variant you are dealing with.

Depending on the cause of the anxiety disorder, it may become a long-term challenge. In some cases it is accompanied by mood disorders. The condition often improves with medication and psychological counselling known as psychotherapy. Making lifestyle changes and using relaxation techniques can also bring about improvement in the condition.

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2. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Arlington, VA: APA Press; 2013.
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