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Objective (1) Describe the association between hearing loss and dysfunction of each of the five vestibular end-organs – the horizontal, superior and posterior semicircular canals, saccule and utricle – in older individuals. (2) Evaluate whether hearing loss and vestibular end-organ deficits share any risk factors. Study design Cross-sectional study. Setting Academic medical center. Patients Fifty-one individuals age ≥70. Interventions Audiometry, head-thrust dynamic visual acuity (htDVA), sound-evoked cervical vestibular-evoked myogenic potential (cVEMP) and tap-evoked ocular VEMP (oVEMP). Main Outcome Measures Audiometric pure-tone averages (PTA), htDVA LogMAR scores as a measure of semicircular canal function in each canal plane, and cVEMP and oVEMP amplitudes as a measure of saccular and utricular function, respectively. Results We observed a significant correlation between hearing loss at high frequencies and reduced cVEMP amplitudes (or reduced saccular function; r = −0.37, p < 0.0001) in subjects age ≥70. In contrast, hearing loss was not associated with oVEMP amplitudes (or utricular function), or htDVA LogMAR scores (or semicircular canal function) in any of the canal planes. Age and noise exposure were significantly associated with measures of both cochlear and saccular dysfunction. Conclusion The concomitant decline in cochlear and saccular function associated with aging may reflect their common embryologic origin in the pars inferior of the labyrinth. Noise exposure appears to be related to both saccular and cochlear dysfunction. These findings suggest a potential benefit of screening individuals with presbycusis – particularly those with significant noise exposure history – for saccular dysfunction, which may contribute to fall risk in the elderly.

Objective: To assess the prevalence of vestibular dysfunction in older adults using the head impulse test (HIT) and to assess the independent influence of HIT abnormalities on gait speed and fall risk in older individuals. Study Design: Cross-sectional study. Setting: Tertiary care academic medical center. Patients: Fifty community-dwelling individuals age 70 and older. Interventions: HIT (abnormal HIT defined as right or left HIT abnormality), visual acuity, monofilament testing, and grip strength. Main Outcome Measures: Gait speed on a 4-meter walk and a history of falls (including number of falls) in the last 1 and 5 years. Results: The participants' mean age was 77 years (range, 70Y95 yr); 52% were female subjects. Fifty percent of participants had an abnormal HIT. An abnormal HIT was significantly associated with a 0.23 m/s reduction in gait speed (p = 0.042), 0.44 more falls in the last 1 year (p = 0.047), and a 5-fold increase in the odds of falling in the last 5 years (p = 0.024) in multivariate analyses adjusted for age, sex, and other balance and fall risk factors. Conclusion: We observed that half of the community-dwelling older individuals in our study had evidence of vestibular dysfunction, which was significantly associated with gait speed and fall risk in adjusted analyses. Screening for vestibular impairment using the simple HIT and directing targeted vestibular therapy may be important to reduce gait impairment and fall risk in older individuals.The vestibular system is integral to balance control and locomotion. A recent epidemiologic analysis using data from the National Health and Nutrition Examination Survey (NHANES) found that vestibular dysfunction is highly prevalent among older individuals and significantly increases fall risk (1). In this study, vestibular dysfunction was defined as a subject's inability to stand with their eyes closed on a foam pad, whereby somatosensory and visual cues are eliminated and the subject is relying exclusively on vestibular information to maintain standing balance. A limitation of such postural tests is their lack of specificity in measuring peripheral vestibular function, given that they may reflect central processing and efferent motor output function as well. As such, the specific prevalence of peripheral vestibular dysfunction in older individuals and their influence on clinically significant outcomes remain unclear.In this report, we evaluated the prevalence of vestibular dysfunction in a cohort of ''normative'' older adults using the head impulse test (HIT), a clinical test that specifically measures vestibulo-ocular reflex (VOR) function. The HIT has been well validated in younger populations, and its use has been expanded to older individuals (2Y4). We also consider the influence of vestibular dysfunction on clinically significant outcomes in older individuals including gait speed and fall risk, using multivariate analyses adjusted for other balance and fall risk factors. We anticipate that a greater understanding of the frequency and clinical impli...

Objective To describe the performance of healthy older adults on common clinical vestibular tests. Patients Fifty community-dwelling older adults aged 70 and older, with mean age of 77.2 ± 6.1 years and range of 70 to 95 years. Intervention(s) Clinical vestibular tests, including spontaneous and head-shaking nystagmus, head impulse test (HIT), bucket test of subjective visual vertical, modified Romberg test (MRT), and Dizziness Handicap Inventory (DHI). Main Outcome Measure(s) Prevalence of abnormal vestibular tests and DHI score. Results We observed a 36% and 44% prevalence of abnormal right and left horizontal HIT, respectively. The bucket test was abnormal in 18% of participants; head-shaking nystagmus was present in 2%, and no participant had spontaneous nystagmus. Approximately 68% of participants had abnormal MRT. Abnormal horizontal HIT and MRT were significantly more prevalent among individuals age 80 years and older compared with those age 70 to 79 years (p < 0.05). Mean DHI score was 5.6 ± 11.2, consistent with no self-reported dizziness handicap. Conclusion This study documents the expected performance of normative older adults on vestibular tests commonly administered in the neurotology clinic. We observed a high prevalence of abnormalities on clinical vestibular testing in healthy older adults, although self-perceived dizziness handicap was low. Further studies using newly available clinical testing methods (e.g., video HIT) may identify finer gradations of vestibular function in older individuals and the levels of vestibular loss associated with functional impairment.