Clinical Psychiatry

Secondary anxiety syndrome

ICD-10F06.4Organic anxiety disorder
DSM-5-TRF06.4Anxiety Disorder Due to Another Medical Condition

1. Definition and nosology

Secondary Anxiety Syndrome (ICD-11: 6E63; DSM-5-TR: F06.4 Anxiety Disorder Due to Another Medical Condition) — anxiety or panic symptoms as a direct physiological consequence of another medical condition.

2. History

Development of consultation-liaison psychiatry; formalization from DSM-III-R (1987).

3. Epidemiology

  1. Frequency of anxiety is high in chronic medical conditions (cardiac, COPD, endocrine).
  2. In hyperthyroidism, 60–70% have anxiety symptoms.
  3. Caffeine, stimulant-induced anxiety.

4. Etiology and pathogenesis

  • Endocrine — hyperthyroidism, pheochromocytoma, hypoglycemia.
  • Cardiac — arrhythmia, myocardial infarction, mitral valve prolapse.
  • Respiratory — COPD, asthma, pulmonary embolism.
  • Neurological — TBI, Parkinson’s, MS.
  • Substance/medication — caffeine, stimulant, corticosteroid, β-blocker (paradoxical), benzodiazepine/alcohol withdrawal.
  • Vestibular disorders.

5. Clinical features

  • GAD, panic attack, OCD-like symptoms in the context of a medical condition.
  • Atypical features (late onset, focal symptoms).

6. Diagnosis

Medical evidence + distress symptoms + temporal congruence.

6.1 Differences between sources

DSM-5-TR / ICD-11 — same.

6.2 Diagnostic algorithm

  • Clinical interview.
  • Medical evaluation — TSH, glucose, cardiac, vestibular.
  • Medication and caffeine history.
  • Toxicology.

6.3 Differential diagnosis

  1. Primary anxiety disorders (6B00–6B0Z);
  2. Delirium;
  3. Adjustment disorder.

7. Examination and assessment

  • GAD-7, HAM-A.
  • TSH, glucose, ECG.
  • Toxicology.

8. Treatment

  • Etiological treatment.
  • Symptomatic — SSRIs for residual anxiety; benzodiazepines short-term for acute condition.
  • Caffeine restriction.

8.1 Treatment methods

  1. Etiological Intervention — Correction of medical condition.
  2. SSRI For Residual Anxiety — For residual symptoms after correction of medical condition.

9. Prognosis

Significant improvement with etiological intervention.

10. Myths and misconceptions

Myth 1: “Anxiety in a patient with a medical illness is ‘normal’”

Evidence: Clinical distress worsens the course of the medical condition; intervention required.

Myth 2: “Anxiolytics are first-line in hyperthyroidism”

Evidence: The primary is thyroid correction; β-blocker (propranolol) is a symptomatic adjunct.

Myth 3: “Caffeine is safe”

Evidence: High doses can cause panic, anxiety, and tachycardia; limiting intake is recommended.

11. Sources

  1. WHO. ICD-11. 6E63 Secondary anxiety syndrome. 2024.
  2. APA. DSM-5-TR. 2022.
  3. Levenson J.L. (ed.). APA Publishing Textbook of Psychosomatic Medicine and Consultation-Liaison Psychiatry. 3rd ed. 2018.