Illness Anxiety Disorder

Illness anxiety disorder is preoccupation with having or acquiring a serious illness with minimal or no somatic symptoms, high health anxiety and excessive health related behaviours, for 6 months or more.

• Prevalence 1.3 to 10%; both sexes equally; replaces most hypochondriasis.
• Care seeking type (frequent consultation) or care avoidant type.
• Fuelled by internet searching, previous illness or family illness, and anxious temperament.
• Comorbid depression, GAD and OCD.

• Persistent fear of disease (cancer, dementia, heart disease), repeated body checking, reassurance seeking, seeking multiple opinions or avoiding healthcare.
• Normal examination, brief relief after reassurance followed by new worry.
• Functional impairment, relationship strain.

• Clinical, using the Health Anxiety Inventory or Whiteley Index.
• Appropriate baseline investigation of reported symptoms, then limit further tests.
• Exclude somatic symptom disorder (prominent symptoms), delusional disorder (fixed belief), OCD, panic disorder, depression, and true medical illness.
• Assess suicide risk.

• CBT for health anxiety (12 to 16 sessions: exposure, reassurance and checking reduction, behavioural experiments) is first line, with response in 50 to 70%.
• SSRIs: fluoxetine 20 to 60 mg daily, sertraline 50 to 200 mg, paroxetine 20 to 40 mg; allow 12 weeks.
• Practical GP strategy: scheduled brief visits, single clinician, explanation of benign nature, avoid repeat investigations and repeated reassurance.
• Limit internet searching; manage comorbid depression.
• Follow up regularly.