Vertigo Diagnosis and Management in Primary Care: A Comprehensive Guide for Clinicians

Vertigo, the sensation of self or environmental motion when no such motion exists, is a common complaint in primary care settings. It is crucial to differentiate true vertigo from other forms of dizziness to ensure accurate diagnosis and effective management. This article provides a comprehensive overview of vertigo, focusing on its classification, causes, symptoms, diagnosis, and management strategies relevant to primary care physicians.

Understanding Vertigo and Dizziness

It’s essential to distinguish vertigo from the broader term “dizziness.” Dizziness is a non-specific term patients often use to describe a range of sensations. These can be categorized into four subtypes:

1. Vertigo: A hallucinatory sensation of movement, either of the surroundings rotating around the patient (objective vertigo) or the patient rotating in space (subjective vertigo).
2. Presyncope: A feeling of impending faint, often due to reduced cerebral blood flow.
3. Light-headedness: A vague sensation of giddiness or wooziness, without a sense of spinning.
4. Disequilibrium: A feeling of imbalance or unsteadiness, particularly when walking or standing.

While patients may use “dizziness” and “vertigo” interchangeably, accurate differentiation is crucial for diagnosis and management. True vertigo specifically points towards a disturbance in the vestibular system.

Classification of Vertigo: Central vs. Peripheral

Vertigo is broadly classified into two categories based on its origin:

1. Peripheral Vertigo: Arises from disorders of the inner ear or the vestibulocochlear nerve (VIIIth cranial nerve). This is the more common type encountered in primary care.
2. Central Vertigo: Originates from disorders within the brainstem or cerebellum. Central vertigo is less frequent but can indicate serious underlying neurological conditions.

Understanding this distinction is vital as it guides diagnostic approaches and management strategies.

Incidence and Prevalence of Vertigo in Primary Care

Dizziness is a frequent complaint in primary care, but true vertigo accounts for a significant portion of these cases. Studies indicate:

• Approximately 30% of patients presenting with dizziness in community-based studies are diagnosed with vertigo. This proportion increases to over 50% in older populations.
• A survey of adults aged 18-65 revealed that 7% reported experiencing true vertigo within the past year.
• A general practitioner can expect to see a considerable number of patients with vertigo annually.

Notably, the majority of vertigo cases seen in primary care are attributed to three conditions: benign paroxysmal positional vertigo (BPPV), vestibular neuronitis, and Ménière’s disease.

Causes of Vertigo: Differentiating Factors

A wide array of conditions can trigger vertigo. Identifying the presence or absence of associated deafness or central nervous system (CNS) signs is critical in narrowing down the differential diagnosis.

| Table 1: Causes of Vertigo |
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Vertigo: Differentiating Central and Peripheral Causes

Vertigo can originate from central or peripheral lesions. It’s also recognized that psychogenic factors or conditions limiting neck movement, like cervical spondylosis or whiplash injuries, can induce vertigo. Determining whether the vertigo is of peripheral or central origin is paramount for appropriate clinical management.

Historical details are invaluable in distinguishing between peripheral and central vertigo:

1. Timing and Duration of Vertigo Episodes:
2. Provoking or Exacerbating Factors: Activities or positions that trigger or worsen symptoms.
3. Associated Symptoms:
   • Pain
   • Nausea and vomiting
   • Neurological symptoms (e.g., double vision, weakness, numbness)
   • Hearing loss or tinnitus

Characteristics of Central Vertigo:

• Gradual Onset: Typically develops slowly over time, except in acute vascular events like stroke.
• Neurological Signs: Often accompanied by other neurological deficits.
• Auditory Symptoms: Less common than in peripheral vertigo.
• Severe Imbalance: Marked difficulty maintaining balance.
• Nystagmus: Can be vertical, horizontal, or torsional; importantly, it is not suppressed by visual fixation.

Characteristics of Peripheral Vertigo:

• Sudden Onset: Episodes are typically abrupt and intense.
• Auditory Symptoms: Frequently associated with hearing loss, tinnitus, or a sensation of fullness in the ear.
• Less Severe Imbalance: Balance issues are present but often less pronounced than in central vertigo.
• Nystagmus: Typically horizontal or torsional, and is suppressed by visual fixation.

The duration of vertigo episodes and the presence of auditory symptoms are key differentiators between various vestibular pathologies, as outlined in Table 2.

| Table 2: Timing of Symptoms in Vertigo |
| :————————————- | :——————- | :—————————- | :————————- |
| Pathology | Duration of Episode | Associated Auditory Symptoms | Peripheral or Central Origin |
| Benign Paroxysmal Positional Vertigo | Seconds | No | Peripheral |
| Vestibular Neuronitis | Days | No | Peripheral |
| Ménière’s Disease | Hours | Yes | Peripheral |
| Perilymphatic Fistula | Seconds | Yes | Peripheral |
| Transient Ischemic Attack (TIA) | Seconds / Hours | No | Central |
| Vertiginous Migraine | Hours | No | Central |
| Labyrinthitis | Days | Yes | Peripheral |
| Stroke | Days | No | Central |
| Acoustic Neuroma | Months | Yes | Peripheral |
| Cerebellar Tumour | Months | No | Central |
| Multiple Sclerosis | Months | No | Central |

Differentiating true vertigo from non-rotatory dizziness is crucial. Asking patients if they feel “light-headed or as if the world was spinning” can help clarify the nature of their dizziness.

Key Historical Points to Elicit:

1. Onset: Identify specific triggers like flying, head trauma, or sudden movements.
2. Duration:
   • Seconds: Suggestive of BPPV or perilymphatic fistula.
   • Hours: Common in Ménière’s disease or vertiginous migraine.
   • Days to Weeks: Typical of vestibular neuronitis, labyrinthitis, or post-head trauma vertigo.
   • Years: Consider psychogenic causes or chronic conditions.
3. Associated Auditory Symptoms: Hearing loss, tinnitus, aural fullness suggest peripheral causes. Rare in central lesions.
4. Other Associated Symptoms:
   • Nausea and vomiting are common in vestibular (peripheral) vertigo.
   • Neurological symptoms (visual disturbances, dysarthria, weakness) raise suspicion for central lesions.

Physical Examination and Signs in Vertigo

A thorough physical examination is essential in evaluating vertigo. Key components include:

1. Otoscopic Examination: Examine the ear drums for:

   • Vesicles: May indicate Ramsay Hunt syndrome (herpes zoster oticus).
   • Cholesteatoma: An abnormal skin growth in the middle ear.

2. Tuning Fork Tests: Rinne and Weber tests to assess for hearing loss, differentiating between conductive and sensorineural hearing loss.

3. Cranial Nerve Examination: Assess all cranial nerves, focusing on:

   • Nerve palsies (particularly CN V, VII, VIII).
   • Sensorineural hearing loss (CN VIII).
   • Nystagmus (CN III, IV, VI, VIII). Observe direction, presence with fixation, and fatiguability.

4. Hennebert’s Sign: Induce vertigo or nystagmus by applying pressure to the tragus or external auditory meatus. Suggests a perilymphatic fistula, especially in the context of trauma or surgery.

5. Gait and Balance Tests:

   • Romberg’s Test: Assesses proprioception, vestibular function, and vision. While not specific for vertigo, it can reveal balance deficits.
   • Heel-to-Toe Walking Test: Evaluates coordination and balance.
   • Unterberger’s Stepping Test: Patient marches in place with eyes closed. Rotation to one side may indicate a labyrinthine lesion on that side.

6. Dix-Hallpike Maneuver: Crucial for diagnosing BPPV. Observe for characteristic rotatory nystagmus upon rapidly moving the patient from sitting to supine with the head turned to one side. In BPPV, the nystagmus is typically:

   • Direction-changing: Appears when testing one ear and reverses or disappears when testing the other.
   • Fatigable: Decreases with repeated testing.
   • Latency: A brief delay between the maneuver and the onset of nystagmus.
   • Torsional: Rotational movement of the eyes.

7. Head Impulse Test (Head Thrust Test): Useful for identifying acute vestibulopathy. Assess vestibulo-ocular reflex (VOR) by asking the patient to fixate on your nose while you rapidly rotate their head horizontally. A corrective saccade (eye movement to refixate) indicates vestibular hypofunction on the side of the head turn.

8. Caloric Testing: Irrigation of the external auditory canal with cold or warm water or air to stimulate the vestibular system. Less commonly used in primary care but may be performed in specialist settings to assess vestibular function.

Investigations and Testing for Vertigo

In many cases, a detailed history and physical examination are sufficient to diagnose the cause of vertigo, particularly in common conditions like BPPV and vestibular neuronitis. However, further investigations may be necessary in certain situations.

1. Audiometry: Specialized hearing tests can be helpful in diagnosing Ménière’s disease, where low-frequency sensorineural hearing loss is a characteristic feature.

2. Laboratory Tests: Consider basic blood tests (complete blood count, blood glucose, electrolytes) to rule out general medical conditions like anemia, hypoglycemia, or electrolyte imbalances that can present with dizziness.

3. Neuroimaging (CT or MRI of the Brain): Indicated if central causes of vertigo are suspected based on history or examination findings. Red flags for central vertigo include:

   • Sudden onset vertigo with persistent symptoms.
   • Vertigo associated with neurological symptoms or signs (headache, gait disturbance, ataxia, weakness, dysarthria, diplopia).
   • Atypical nystagmus (vertical, persistent, direction-changing, or unequal in each eye).
   • Suspicion of cerebellopontine angle tumor or other intracranial pathology.

Management of Vertigo in Primary Care

The ideal treatment for vertigo targets the underlying cause. However, symptomatic management is often necessary, particularly during acute episodes.

1. Medical Management:

   • Vestibular Suppressants: Medications can help alleviate acute vertigo symptoms. Common options include:

     • Betahistine: An analogue of histamine, thought to improve microcirculation in the inner ear and may be beneficial in Ménière’s disease and other peripheral vestibular disorders. Doses range from 8-16mg up to three times daily.
     • Cinnarizine: An antihistamine and calcium channel blocker, effective in reducing vertigo and motion sickness. Usual dose is 15-30 mg three times daily.
     • Prochlorperazine: A phenothiazine antiemetic, particularly useful for rapid relief of acute vertigo associated with nausea and vomiting. Available in tablet (5-10mg), buccal (3mg), intramuscular injection (12.5mg), and rectal suppository (25mg) formulations. Should be reserved for short-term use due to potential side effects.

   • Corticosteroids: In cases of vestibular neuronitis, oral corticosteroids (e.g., prednisolone) may be prescribed in the acute phase to reduce inflammation and potentially improve vestibular recovery.

2. Vestibular Rehabilitation Exercises (VRE): A crucial component of long-term management, especially for peripheral vestibular disorders. Cawthorne-Cooksey exercises are a classic example. VRE aims to promote central compensation for vestibular deficits, reducing dizziness and improving balance. Exercises typically involve:

   • Gaze Stabilization Exercises: Moving the eyes and head while maintaining focus on a target.
   • Habituation Exercises: Repeated exposure to provocative stimuli to reduce symptom sensitivity.
   • Balance Training: Exercises to improve postural stability and gait.

3. Epley Maneuver (Canalith Repositioning Maneuver): The primary treatment for posterior canal BPPV, the most common type. This maneuver aims to relocate otolith debris from the posterior semicircular canal back into the utricle, resolving the vertigo. Contraindications include severe carotid stenosis, unstable heart disease, severe cervical spine disease, and advanced rheumatoid arthritis affecting the neck.

4. Lifestyle Modifications: For recurrent vertigo, particularly in Ménière’s disease, lifestyle adjustments may be beneficial:

   • Dietary Salt Restriction: May help reduce endolymphatic hydrops in Ménière’s disease.
   • Fluid Management: Maintaining adequate hydration but avoiding excessive fluid intake.
   • Smoking Cessation and Limiting Caffeine and Alcohol: These substances can exacerbate vertigo symptoms in some individuals.

Important Considerations in Vertigo Management:

• Sedation: Warn patients about potential drowsiness with vestibular suppressant medications, particularly antihistamines and benzodiazepines.
• Prochlorperazine Side Effects: While less sedating than some antihistamines, prochlorperazine can cause dystonic reactions, especially in children and young women.
• Benzodiazepines: Generally not recommended for routine vertigo management due to potential for dependence and limited long-term benefit.

Consultation and Referral for Vertigo

Referral to specialist care is warranted in certain situations:

Referral to Secondary Care (ENT or Neurology) is Indicated For:

1. Recurrent or Persistent Vertigo Episodes: Especially if the diagnosis is unclear or symptoms are not controlled with primary care management.
2. Vertigo with Neurological Symptoms: Dysphasia, paraesthesiae, weakness, diplopia, or other neurological deficits suggestive of central pathology.
3. Associated Sensorineural Hearing Loss: Requires evaluation by an ENT specialist to investigate potential inner ear disorders.
4. Abnormal Otoscopic Findings: Inadequate visualization of the tympanic membrane or presence of abnormalities like cholesteatoma necessitate ENT referral.
5. Atypical Nystagmus: Non-horizontal, persistent, direction-changing, or unequal nystagmus warrants neurological assessment.
6. Positive Fistula Sign: Suggests perilymphatic fistula and requires ENT evaluation.

Specific Referral Pathways:

• Hearing Problems and Vertigo: Refer to an ENT specialist.
• Vertigo without Hearing Problems, but with Suspected Central Cause: Refer to a neurologist.

Management While Awaiting Referral:

• Symptomatic Treatment: Consider short-term vestibular suppressants (no longer than one week) to alleviate acute symptoms. Prolonged use can hinder vestibular compensation.
• Discontinue Symptomatic Medications Before Specialist Appointment: Advise patients to stop vestibular suppressants 48 hours before specialist consultation as these medications can interfere with diagnostic tests like the Dix-Hallpike maneuver.
• Seek Urgent Specialist Advice if Symptoms Worsen.

When to Consider Hospitalization for Vertigo

Hospital admission or urgent referral is necessary in the following scenarios:

1. Severe Nausea and Vomiting: Inability to tolerate oral fluids due to intractable vomiting, leading to dehydration.

2. Acute Vertigo with Neurological Symptoms Suggestive of Central Cause:

   • Very sudden onset of vertigo (within seconds) that persists.
   • Vertigo accompanied by new-onset headache (especially occipital), gait disturbance, truncal ataxia, numbness, dysarthria, or weakness. May indicate stroke, TIA, or multiple sclerosis.

3. Acute Deafness with Vertigo: Sudden onset unilateral hearing loss associated with vertigo, without typical Ménière’s disease features (tinnitus, aural fullness). Suggests possible acute ischemia of the labyrinth or brainstem, or inflammatory/infectious causes. Emergency ENT referral (within 12 hours) is crucial as prompt treatment may restore hearing.

The urgency of referral and hospitalization depends on the severity of symptoms and the suspected underlying diagnosis.

Patient Resources:

• The Ménière’s Society: www.menieres.org.uk
• Patient.co.uk: www.patient.co.uk/doctor/Vertigo.htm

Conclusion

Vertigo is a common and often distressing symptom encountered in primary care. A systematic approach to history taking, physical examination, and targeted investigations is essential for accurate diagnosis. Understanding the distinction between peripheral and central vertigo, as well as common vestibular syndromes like BPPV, vestibular neuronitis, and Ménière’s disease, enables primary care physicians to effectively manage most cases. Appropriate use of vestibular suppressants, vestibular rehabilitation, and canalith repositioning maneuvers like the Epley maneuver are key treatment strategies. Timely referral to specialist care is crucial for complex or atypical cases, ensuring optimal outcomes for patients with vertigo.

References

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