Dizziness
Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management
Definition
Dizziness is a nonspecific term that refers to sensations of light headedness, disequilibrium, or vertigo (a false sense of motion).
Aetiology
- Peripheral causes: benign paroxysmal positional vertigo (BPPV), Ménière’s disease, vestibular neuritis, labyrinthitis.
- Central causes: stroke, transient ischaemic attack (TIA), multiple sclerosis, vestibular migraine.
- Cardiovascular causes: postural hypotension, arrhythmias, aortic stenosis.
- Metabolic causes: hypoglycaemia, anaemia, dehydration.
- Psychogenic causes: anxiety, panic attacks, hyperventilation syndrome.
Pathophysiology
- Peripheral vestibular dysfunction disrupts balance and coordination signals to the brain.
- Central nervous system lesions affecting the brainstem or cerebellum impair coordination.
- Cardiovascular causes result in inadequate cerebral perfusion leading to light-headedness or syncope.
Risk Factors
- Older age.
- Hypertension, diabetes, or cardiovascular disease.
- History of migraine or vestibular disorders.
- Use of ototoxic medications (e.g., aminoglycosides, diuretics).
- Dehydration or prolonged bed rest.
Signs and Symptoms
- Vertigo: spinning sensation, worsened by head movement.
- Light headedness: sensation of faintness or presyncope.
- Imbalance: difficulty maintaining posture and coordination.
- Nausea and vomiting: common in vestibular disorders.
- Hearing loss or tinnitus: suggests Ménière’s disease or labyrinthitis.
- Neurological deficits: diplopia, dysarthria, limb weakness (suggests central cause).
Investigations
- Clinical examination: Dix-Hallpike manoeuvre for BPPV, Romberg’s test for balance assessment.
- Blood tests: FBC (anaemia), glucose (hypoglycaemia), U&Es (electrolyte imbalance).
- ECG and Holter monitoring: assess for arrhythmias.
- MRI brain: if central causes (stroke, multiple sclerosis) are suspected.
- Pure tone audiometry: assess for associated hearing loss.
Management
1. Peripheral Causes:
- BPPV: Epley manoeuvre, vestibular rehabilitation exercises.
- Ménière’s disease: low salt diet, betahistine, vestibular suppressants.
- Vestibular neuritis: short course of corticosteroids, vestibular rehabilitation.
2. Central Causes:
- Urgent stroke/TIA assessment if focal neurological signs are present.
- Migraine prophylaxis (e.g., propranolol, amitriptyline) if vestibular migraine diagnosed.
3. Cardiovascular and Metabolic Causes:
- Treat underlying arrhythmias or valvular disease.
- Increase hydration and dietary salt intake in postural hypotension.
- Correct anaemia or electrolyte imbalances.
4. Referral:
- ENT specialist: for persistent vertigo or suspected Ménière’s disease.
- Neurology: if stroke, vestibular migraine, or central cause is suspected.
- Cardiology: for suspected arrhythmias or cardiovascular causes.
- Physiotherapy: for vestibular rehabilitation therapy.