Tinnitus

Tinnitus is a sound heard with no external source. It is chronic once it has lasted at least 3 months.

Subjective tinnitus, the usual form, has no sound source and reflects abnormal inner ear or central activity. Objective tinnitus has a real vascular or muscular source and may be audible with a stethoscope. Somatosensory tinnitus, a subjective subtype, changes with head, neck or jaw movement.

Burden varies: grades 1 and 2 are compensated; grades 3 and 4 are decompensated, with major impact and often anxiety, depression or poor sleep.

In a 12-country European survey, 14.7% of adults had any tinnitus, 6.0% bothersome and 1.2% severe; prevalence rose with age and worse hearing.

In the Rotterdam Study (50 years or over), 21.4% had tinnitus more than once a week and those with hearing impairment had about twice the odds (OR 2.27), but prevalence did not differ across 5-year age bands: unlike the all-adult survey, no rise after 50. In this community cohort, 12.3% of those affected said it interfered with daily life.

An inner ear process often comes first, and pitch tends to lie where hearing loss is greatest; a primary central cause is rare.

Common links: hearing loss (ageing or noise), earwax or ear infection, head or neck injury, and drugs, especially at high doses (NSAIDs including aspirin, certain antibiotics, anti-cancer drugs, antimalarials, antidepressants).

Less common: Ménière's disease, jaw joint problems, vestibular schwannoma, vascular disease, diabetes, thyroid disorders.

History: side, onset, hearing loss, vertigo, head or jaw modulation, medicines, head and neck irradiation. Ask about anxiety, depression and sleep; tinnitus can mask depression.

Basic assessment, once in chronic tinnitus or on marked worsening: ear microscopy, pure-tone and speech audiometry, tympanometry, blood pressure; auscultate ear and carotid if pulse-synchronous. Score distress with a validated tool such as the Tinnitus Handicap Inventory.

Needing further or specialist assessment: acute onset with sudden hearing loss (guidelines recommend steroids, on moderate evidence; not without measurable hearing loss); one-sided tinnitus or asymmetric hearing loss; pulsatile tinnitus; vertigo or focal neurological signs; headache; high distress or suspected depression or anxiety.

Imaging is chosen individually. MRI for unilateral hearing loss, suspected retrocochlear pathology, vertigo or neurological disease. Doppler and angiography for pulse-synchronous tinnitus (such as arteriovenous malformation, aneurysm or carotid stenosis). Petrous bone CT for bony destruction.

Treat any cause found: dealing with earwax or jaw joint problems can greatly reduce symptoms.

Counselling for every patient: explain findings, reassure once assessment finds it benign, aim for habituation rather than elimination.

Cognitive behavioural therapy: strong recommendation. A Cochrane review found low-grade evidence of less impact on quality of life with few side effects; long-term effects are uncertain and average ages were 43 to 70 years.

Hearing aids for tinnitus with hearing loss (evidence moderate or weak) and cochlear implants for profound loss, even unilateral.

Treat comorbid anxiety and depression under their own guidelines, where drugs may be used. Manual therapy or physiotherapy if neck or jaw problems modulate the tinnitus. Tinnitus retraining therapy may be considered long term (at least 12 months), without noise generators.

Drugs for tinnitus itself (including betahistine, ginkgo, antidepressants, benzodiazepines, steroids and gabapentin), because efficacy data are insufficient and side effects can be significant; and food supplements. A network meta-analysis favoured amitriptyline, acamprosate and gabapentin over placebo, but routine use remains discouraged.

Noise generators, sound therapy, notched music; transcranial magnetic or electrical, vagus nerve, bimodal and invasive brain stimulation; TENS, low-level laser and acupuncture.

Sources differ: NIDCD still lists sound therapy devices, and a minority vote in the German guideline held that transcranial magnetic stimulation can be considered.