Defining Anxiety 

Anxiety is a normal human emotion that everyone experiences from time to time. People may feel anxious when facing problems, challenges, changes, or difficult decisions. Anxiety disorders, however, are dysfunctional responses to anxiety-inducing situations. The difference between normal anxiety and an anxiety disorder is that anxiety disorders cause such severe distress as to interfere with someone's ability to lead a normal life. "Anxiety disorder" refers to any of a number of specific disorders, including generalized anxiety disorder, phobia, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, and social anxiety disorder.

Anxiety disorders are defined by excessive worry, apprehension, and fear about future events or situations, either real or imagined. Specifically, symptoms may include:

• feelings of panic, fear, or uneasiness
• uncontrollable and obsessive thoughts
• flashbacks to traumatic events
• problems sleeping
• nightmares
• shortness of breath
• nausea
• muscle tension
• dizziness
• heart palpitations
• dry mouth
• cold or sweaty hands

Anxiety disorders are diagnosed in between 4% and 10% of older adults; however, this figure is likely an underestimate of the true incidence due to the tendency of adults to minimize psychiatric problems and to focus on physical symptoms.

Etiology

Anxiety in and of itself is not a bad thing. In fact, the hormonal response involved in anxiety evolved to help humans react to danger—it better prepares them to recognize threats and to act accordingly to ensure their safety. Such sensory information is processed by the amygdala, which communicates information about potential threats to the rest of the brain. However, anxiety becomes counterproductive and thus is deemed "disordered" when it is experienced with such intensity that it impedes social functioning.

Anxiety disorders develop as the result of the interaction of genetic (inherited) and environmental factors. Neurologically speaking, increased amygdala reactivity is correlated with increased fear and anxiety responses. Low levels of GABA (a neurotransmitter in the brain that reduces central nervous system activity) can contribute to anxiety, and serotonin, glutamate, and the 5-Ht2A receptor have also all been implicated in the development of anxiety disorders.

In addition to biological factors, anxiety disorders can also be caused by various life stresses, such as financial worries or chronic physical illness. Severe anxiety and depression can also be induced by sustained alcohol abuse; with prolonged sobriety these symptoms usually decrease. Even moderate sustained alcohol use may increase anxiety and depression levels in some individuals. Caffeine, alcohol, and benzodiazepine dependence can worsen or cause anxiety and panic attacks.

Anxiety and stress

Anxiety disorders can arise in response to life stresses such as financial worries or chronic physical illness.

Treatment

Treatment options for anxiety disorders include lifestyle changes, therapy, and medication. The most common intervention is cognitive behavioral therapy (CBT), which aims to help the person identify and challenge their negative thoughts (cognitions) and change their reactions to anxiety-provoking situations (behaviors). 

In terms of medication, SSRIs are most commonly recommended. Benzodiazepines are also sometimes indicated for short-term or "as-needed" use. MAOIs such as phenelzine and tranylcypromine are also considered effective and are especially useful in treatment-resistant cases, but dietary restrictions and medical interactions may limit their use.