Presbyvestibulopathy (Age-Related Vestibular Loss)

Definition and epidemiology

Presbyvestibulopathy (PVP) is a chronic vestibular syndrome caused by mild, bilateral, age-related loss of peripheral vestibular function. In criteria published in 2019, the Bárány Society defined it as an intermediate level between normal vestibular function and bilateral vestibulopathy. The concept draws on age-related hearing loss (presbycusis) and age-related changes in vision (presbyopia): there is no complete loss, but the mild decline is enough to affect daily life (Agrawal et al., 2019).

Vestibular loss is common in older people. Population studies suggest that about half of people over 60 have measurable vestibular loss; dizziness or imbalance is reported by 20-30% of those over 65 and by more than half of community-dwelling people over 80. In a German study, the one-year prevalence of vestibular vertigo was 7.2% at ages 60-69 and 8.8% over 80 (Agrawal et al., 2019). In a US national health survey of 5086 adults over 40, the prevalence of vestibular dysfunction on a modified Romberg test was 35.4%, rising steeply with age (Agrawal et al., 2009). Data on how many people meet the PVP criteria in the population are still limited.

Symptoms and signs

Under the Bárány criteria, symptoms must have lasted at least three months, with at least two of the following four: postural imbalance or unsteadiness, gait disturbance, chronic dizziness and recurrent falls (Agrawal et al., 2019). Patients often say their balance is worse in the dark, on uneven ground, in crowds or when they turn their head quickly. Onset is insidious and progression slow; distinct attacks of vertigo are not expected.

In an older person, unsteadiness rarely has a single cause. PVP is often accompanied by reduced vision, reduced sensation from the feet (proprioception), weakness of the leg muscles and age-related changes in cortical, extrapyramidal or cerebellar systems (Agrawal et al., 2019). The same vestibular loss may therefore cause few symptoms in someone whose other senses and strength are intact, but marked unsteadiness and falls in someone with several affected systems.

Causes and risk factors

With ageing, vestibular hair cells in the inner ear, vestibular nerve fibres and neurons in the brainstem vestibular nuclei decline in number. Type I hair cells, which respond to fast head movements, are reported to be disproportionately affected, a pattern likened to presbycusis with its greater effect on high frequencies (Agrawal et al., 2019). Because presbycusis and PVP are both common in the same age group, many older people have both; they can be seen as two faces of age-related change in the inner ear.

Factors associated with vestibular dysfunction include older age and diabetes: in the national survey, the odds were 70% higher in people with diabetes and 40.3% lower in those with education beyond high school (Agrawal et al., 2009). The most serious consequence of vestibular loss is falling. In the same study, people with vestibular dysfunction who reported dizziness had a 12-fold increase in the odds of falling (Agrawal et al., 2009). Vestibular asymmetry has also been linked to hip and wrist fractures (Agrawal et al., 2019).

Audiological and clinical assessment

Under the Bárány Society criteria, all four of the following are required for a diagnosis of PVP (Agrawal et al., 2019):

• A. Chronic vestibular syndrome: lasting at least three months, with at least two of postural imbalance, gait disturbance, chronic dizziness and recurrent falls.
• B. Mild bilateral peripheral vestibular hypofunction: documented by at least one of: bilateral VOR gain between 0.6 and 0.8 on the video head impulse test (vHIT); VOR gain between 0.1 and 0.3 on sinusoidal rotational chair testing (0.1 Hz); or a sum of bithermal maximum peak slow-phase velocities between 6 and 25°/s on each side on caloric testing.
• C. Age 60 years or over.
• D. Not better accounted for by another disease or disorder.

These test values lie just above the thresholds for bilateral vestibulopathy (Strupp et al., 2017), and the distinction is summarised in the table. Because vHIT gain in healthy people is largely preserved into the 80-89 age group (McGarvie et al., 2015), a low gain in an older patient should not be dismissed as ‘just ageing’ and must be interpreted alongside the clinical findings. Caloric testing assesses very low-frequency and vHIT high-frequency head motion, so the tests do not always agree; the criteria therefore accept an abnormal result on any one of them.

Other points to consider in the assessment:

• Positional tests: BPPV is common and easily treated in older people, so the Dix-Hallpike and supine roll tests should always be performed (Agrawal et al., 2019). See BPPV for details.
• Medication: vestibular tests should be carried out without recent use of sedatives such as benzodiazepines, which can suppress the responses (Agrawal et al., 2019).
• Hearing assessment: pure-tone and speech audiometry show any accompanying presbycusis, typically a bilateral, symmetrical sensorineural loss sloping towards the high frequencies. An asymmetric loss, or speech discrimination that is poorer than the thresholds would predict, points to another cause.
• Balance and gait: the Romberg test, tandem gait, dynamic visual acuity and the Timed Up and Go test indicate functional status and falls risk.
• Differential diagnosis: bilateral vestibulopathy, polyneuropathy, cerebellar and extrapyramidal disorders, orthostatic hypotension, medication side effects and Persistent Postural-Perceptual Dizziness (PPPD) should be considered. For a general overview, see an introduction to vertigo and balance disorders.

Treatment and audiological rehabilitation

No drug or operation restores lost vestibular function; the aims of treatment are to support central compensation, help the patient make better use of the other senses and prevent falls. The Bárány document points out that a diagnosis of PVP may encourage earlier and sustained vestibular rehabilitation and treats age-related dizziness as a modifiable problem (Agrawal et al., 2019). The current guideline of the American Physical Therapy Association gives a strong recommendation that people with bilateral peripheral vestibular hypofunction be offered vestibular rehabilitation, comprising gaze stabilisation, balance and gait exercises (Hall et al., 2022).

Fall prevention is an integral part of rehabilitation. In a Cochrane review of exercise to prevent falls in community-dwelling older people, balance and functional exercises reduced the rate of falls by 24% (39 trials, 7920 participants; high-certainty evidence) (Sherrington et al., 2019). Removing hazards at home, suitable footwear, correcting visual problems and a medical review of medicines that can cause dizziness are further elements. Long-term use of vestibular suppressants can slow compensation and is not recommended for chronic unsteadiness; decisions about medication rest with the doctor.

The audiologist contributes to diagnosis through the vestibular test battery, assesses accompanying presbycusis and plans hearing aid fitting where needed. Evidence that hearing aids directly improve balance is limited, but better hearing helps people notice what is happening around them and supports social participation. Scales such as the Dizziness Handicap Inventory and the Activities-Specific Balance Confidence Scale can document the baseline and track progress in rehabilitation.

Impact on quality of life and advice

Unsteadiness and fear of falling have a marked effect on an older person’s independence. People may start to avoid going out, shopping and social activities; reduced activity then further weakens muscles and balance, creating a vicious circle. Fractures from falls can lead to long-term care needs. Accompanying hearing loss can make communication harder and add to isolation.

Practical advice: do the balance exercises you have been given regularly, as their benefit depends on consistent practice. Use a night light at home, remove loose rugs, have grab rails fitted in the bathroom and use the handrail on stairs. Take particular care when walking in the dark or on uneven ground, and ask your physiotherapist whether a walking stick would help. Review your medicines with your doctor at least once a year. Have your hearing and eyesight checked regularly. Note any falls or near-falls and tell your doctor and physiotherapist about them.