What are the causes of dizziness?

Causes of Dizziness

Dizziness can be classified into four main categories: vertigo (42% of cases), presyncope, disequilibrium, and lightheadedness, with specific etiologies in each category that require targeted evaluation and management. 1

Classification of Dizziness Types

1. Vertigo (Sensation of Rotation)

• Peripheral Vestibular Causes:

  • Benign Paroxysmal Positional Vertigo (BPPV) - 42% of vertigo cases in primary care 1
  • Vestibular neuritis - 41% of vertigo cases 1
  • Menière's disease - 10% of vertigo cases in primary care, 43% in specialty settings 1
  • Labyrinthitis 2

• Central Causes:

  • Stroke/TIA - presents with abnormal HINTS exam and neurological deficits 1
  • Multiple sclerosis 3
  • Cerebellar atrophy 3
  • Vestibular migraine - associated with photophobia and history of migraine 1

2. Presyncope (Near-fainting)

• Orthostatic hypotension - especially common in elderly patients 1
• Cardiovascular disorders 3
• Medication side effects - diuretics, β-blockers, calcium antagonists, ACE inhibitors, nitrates 1

3. Disequilibrium (Imbalance)

• Parkinson disease 2
• Diabetic neuropathy 2
• Proprioceptive deficits 4
• Neurological gait disorders 4

4. Lightheadedness (Vague Sensation)

• Psychiatric disorders - depression, anxiety 2
• Hyperventilation syndrome 2
• Medication side effects - antipsychotics, tricyclic antidepressants, antihistamines 1

Diagnostic Approach

Key History Elements

• Timing: episodic vs. continuous
• Triggers: positional changes, standing, exertion
• Associated symptoms: hearing loss, tinnitus, neurological deficits

Physical Examination Tests

1. For Vertigo:

   • Nystagmus evaluation
   • Dix-Hallpike maneuver for BPPV
   • HINTS examination (Head Impulse, Nystagmus, Test of Skew) - more sensitive than early MRI for stroke detection 1

2. For Presyncope:

   • Orthostatic vital signs - blood pressure drop of ≥20 mmHg systolic or ≥10 mmHg diastolic within 3 minutes of standing indicates orthostatic hypotension 1

3. For Disequilibrium:

   • Neurological examination
   • Validated assessment tools: Activities-Specific Balance Confidence Scale, Dizziness Handicap Inventory, Dynamic Gait Index, and Timed Up & Go test 1

Common Pitfalls to Avoid

1. Focusing on the quality of dizziness rather than timing and triggers 1
2. Failing to perform the Dix-Hallpike maneuver in patients with positional vertigo 1
3. Routinely prescribing vestibular suppressants for BPPV 1
4. Missing central causes of vertigo by not performing the HINTS examination 1
5. Ordering unnecessary imaging studies in patients with clear peripheral vertigo 1
6. Overlooking medication side effects as a cause of dizziness 1

Special Considerations

• Elderly Patients: Higher risk for multiple contributing factors including medication effects, orthostatic hypotension, and degenerative conditions 1

• Commercial Drivers: Require comprehensive evaluation due to public safety concerns, with mandatory referral to sleep medicine specialists if specific risk factors are present 1

• Chronic Dizziness: Consider impediments to central vestibular compensation such as visual problems, proprioceptive deficits, or psychological factors 4

• No Diagnosis: In approximately 20% of cases, a definitive diagnosis may not be established despite thorough evaluation 2