Anxiety (Generalized Anxiety Disorder)

Description

• Persistent, excessive, and difficult-to-control worry associated with significant symptoms of motor tension, autonomic hyperactivity, and/or disturbances of sleep or concentration
• System(s) affected: nervous (increased sympathetic tone and catecholamine release), cardiac (tachycardia), pulmonary (dyspnea), and GI (nausea, irregular bowels)

Epidemiology

Prevalence

• Lifetime prevalence in United States: 5.1–11.9%
• Onset at any age but typically during adulthood; median age of onset in the United States is 31 years.
• Female > male (2:1)

Etiology and Pathophysiology

• May be mediated by abnormalities of neurotransmitter systems (serotonin, norepinephrine, γ-aminobutyric acid [GABA])
• Associated with altered regional brain function (increased activity in the amygdala and prefrontal cortex)

Genetics
A serotonin transporter gene (5HT1A) may contribute to GAD.

Risk Factors

• Adverse life events (illness, poverty, etc.)
• Family history
• Comorbid psychiatric disorders (1)

General Prevention

• Physical activity and cardiorespiratory fitness are associated with decreased generalized anxiety.
• Cognitive-behavioral therapy (CBT) and parental intervention in children with early anxiety may protect against GAD (1).

Commonly Associated Conditions

• Major depressive disorder (>60%), dysthymia, bipolar disorder, schizophrenia
• Alcohol/drug abuse; cigarette smoking
• Panic disorder, agoraphobia, phobia, social anxiety disorder, anorexia nervosa, PTSD, ADHD
• Somatoform and pain disorders