Generalized Anxiety Disorder

Generalized anxiety disorder (GAD) is excessive, hard to control worry about multiple domains on most days for at least 6 months, with somatic arousal and functional impairment.

• Lifetime prevalence is 4 to 6%, with a female predominance of about 2:1 and a median onset in the early 30s.
• It is heritable (about 30%) and linked to amygdala prefrontal hyperreactivity and intolerance of uncertainty.
• Comorbid major depression occurs in over 60%, and other anxiety disorders, alcohol misuse and somatic symptom disorders are common.
• It is chronic and relapsing, and raises the risk of cardiovascular disease and suicidality.

• Restlessness, fatigue, poor concentration, irritability, muscle tension and sleep disturbance (three or more required in adults).
• Somatic complaints: headache, palpitations, gastrointestinal upset, tremor, sweating.
• Frequent primary care attendance with unexplained symptoms.
• Red flags: suicidal ideation, substance dependence, new onset in late life (consider medical cause).

• Clinical interview with the GAD-7 (10 or more suggests moderate disease).
• Exclude thyrotoxicosis, phaeochromocytoma, arrhythmia, hypoglycaemia, caffeine and stimulant excess, alcohol or benzodiazepine withdrawal, and drugs (salbutamol, steroids, levothyroxine excess).
• Basic tests: TSH, full blood count, glucose, ECG when palpitations dominate.
• Screen for depression, panic, bipolar disorder and suicide risk.

• Psychoeducation, sleep and caffeine hygiene, exercise.
• CBT (12 to 16 sessions) is first line and equal to medication in efficacy.
• SSRIs and SNRIs: escitalopram 10 to 20 mg daily, sertraline 50 to 200 mg, venlafaxine XR 75 to 225 mg, duloxetine 60 to 120 mg. Start low, expect response over 4 to 6 weeks, and continue 12 months after remission.
• Alternatives: pregabalin 150 to 600 mg daily in divided doses, buspirone 15 to 60 mg daily, hydroxyzine 25 to 50 mg up to three times daily, quetiapine XR 150 mg in refractory cases.
• Benzodiazepines only for short courses (under 2 to 4 weeks) because of dependence.
• Relapse prevention with maintenance medication and booster CBT.