Diagnosis and Management of Generalized Anxiety Disorder and Panic Disorder in Adults

Key points

• Selective serotonin reuptake inhibitors (SSRIs) are considered first-line therapy for generalized anxiety disorder (GAD) and panic disorder (PD).
• Psychotherapy can be as effective as medication; cognitive behavior therapy (CBT) has the best level of evidence.
• Medication should be continued for 12 months after symptoms improve before tapering, to avoid relapse.
• Combined with antidepressants, benzodiazepines may speed recovery but do not improve longer-term outcomes, so they should be used only short term during crises.
• The GAD-7 and the Severity Measure for Panic Disorder are free tools for diagnosis and monitoring.

Overview

This American Family Physician review covers the diagnosis and management of GAD and PD in adults, two of the most common mental disorders in the United States. Both are often missed or misdiagnosed because their symptoms are ascribed to physical causes. Diagnosis requires a broad differential and attention to comorbid conditions. Treatment should be tailored to the individual and often includes medication such as an SSRI and/or psychotherapy.

Epidemiology

Among U.S. adults aged 18 to 64 years, the 12-month prevalence is 2.9% for GAD and 3.1% for PD. Lifetime prevalence of GAD is 7.7% in women and 4.6% in men; for PD it is 7.0% in women and 3.3% in men. The median age of onset of GAD is 30 years. The causes of both disorders are not well understood, and environmental and genetic factors are likely involved.

Diagnosis

GAD typically presents as excessive anxiety about ordinary, day-to-day situations, often with physical symptoms such as sleep disturbance, restlessness, muscle tension, gastrointestinal symptoms and chronic headaches. On the GAD-7, a score of 10 or more has good diagnostic sensitivity and specificity, and scores of 5, 10 and 15 are the cutoffs for mild, moderate and severe anxiety. PD is characterized by recurrent unexpected panic attacks. In these attacks, intense fear typically peaks within about 10 minutes and is accompanied by at least four physical or psychological symptoms. The patient also worries about further attacks or changes behavior to avoid them. Palpitations are the most common physical symptom.

Differential diagnosis and comorbidity

Conditions to exclude include hyperthyroidism, pheochromocytoma, hyperparathyroidism, arrhythmia, obstructive pulmonary diseases, temporal lobe epilepsy and transient ischemic attacks. Other psychiatric disorders, substances such as caffeine, albuterol, levothyroxine or decongestants, and substance withdrawal must also be considered. GAD and PD usually occur with at least one other psychiatric disorder, such as a mood, anxiety or substance use disorder.

Treatment

Medication or psychotherapy is a reasonable initial option, and combining them may be more effective for moderate to severe symptoms. Education, removing triggers such as caffeine and nicotine, better sleep and physical activity can reduce symptoms. Exercising at 60% to 90% of maximal heart rate for 20 minutes three times weekly has been shown to decrease anxiety. Besides SSRIs, first-line options include venlafaxine extended release, and duloxetine and buspirone for GAD. Second-line options include tricyclic antidepressants, pregabalin and quetiapine for GAD, and hydroxyzine. Medications should be titrated slowly and not considered ineffective until they have been used at the high end of the dose range for at least four weeks. Psychotherapy should be given weekly for at least eight weeks to assess its effect.

Frequently asked questions

How long should medication be continued?

Once symptoms have improved, medication should be used for 12 months before tapering to limit relapse; some patients need longer treatment.

Can herbal products be combined with antidepressants?

Caution is needed: St. John's wort, tryptophan, 5-hydroxytryptophan and S-adenosyl-l-methionine increase the risk of serotonin syndrome with SSRIs, and kava has been linked to hepatotoxicity.

When should a patient be referred to psychiatry?

Referral may be indicated for poor response to treatment, atypical presentation or concern about significant comorbid psychiatric illness.

Source

Locke AB, Kirst N, Shultz CG. Diagnosis and Management of Generalized Anxiety Disorder and Panic Disorder in Adults. American Family Physician 2015;91(9):617-624. The journal page notes that a more recent AFP article on this topic is available. This page is a summary prepared by Medpresso from the original publication and is not a substitute for the full text or for medical advice.