Prevalence of Vestibular Disorders in Independent People Over 50 That Experience Dizziness

Abstract

People aged over 50 are the most likely to present to a physician for dizziness. It is important to identify the main cause of dizziness in order to develop the best treatment approach. Our goal was to determine the prevalence of benign paroxysmal positional vertigo (BPPV), and peripheral and central vestibular function in people that had experienced dizziness within the past year aged over 50. One hundred and ninety three community-dwelling participants aged 51-92 (68 ± 8.7 years; 117 females) were tested using the clinical and video head impulse test (cHIT and vHIT) to test high-frequency vestibular organ function; the head thrust dynamic visual acuity (htDVA) test to test high-frequency visual-stability; the dizziness handicap inventory (DHI) to measure the impact of dizziness; as well as sinusoidal and unidirectional rotational chair testing to test low- to mid-frequency peripheral and central vestibular function. From these assessments we computed the following measures: HIT gain; htDVA score; DHI score; sinusoidal (whole-body; 0.1-2 Hz with 30°/s peak-velocity) vestibulo-ocular reflex (VOR) gain and phase; transient (whole-body, 150°/s² acceleration to 50°/s constant velocity) VOR gain and time constant; optokinetic nystagmus (OKN) gain and time constant (whole-body, 50°/s constant velocity rotation). Our study showed that BPPV, and peripheral or central vestibular hypofunction were present in 34% of participants, suggesting a vestibular cause to their dizziness. Over half (57%) of these with a likely vestibular cause had BPPV, which is more than twice the percentage reported in other dizzy clinic studies. Our findings suggest that the physical DHI score and VOR time constant were best at detecting those with non-BPPV vestibular loss, but should always be used in conjunction with cHIT or vHIT, and that the htDVA score and vHIT gain were best at detecting differences between ipsilesional and contralesional sides.

Keywords: benign paroxismal positional vertigo; community dwelling adults; expert panel assessment; peripheral vestibular disorders; vestibulo-ocular reflex.

Figure 1

Histogram of clinical Head Impulse Test (cHIT) results binned as Positive or Negative vs. age (with 5-years bands).

Figure 2

Minimum (between leftward and rightward head rotations) video Head Impulse Test (vHIT) vestibulo-ocular reflex (VOR) gain calculated for each participant vs. their age, clustered by group with group and overall line-fits.

Figure 3

(A) Histogram of htDVA scores binned as normal, borderline, and abnormal vs. age (with 5-years bands). (B) Maximum htDVA score [across all canal planes [left anterior, left posterior, left horizontal, right anterior, right posterior, right horizontal]] calculated for each participant vs. their age, clustered by group with group and overall line-fits.

Figure 4

Histogram of total (Emotional + Functional + Physical) Dizziness Handicap Inventory (DHI) score for each participant vs. their age, clustered by group with group and overall line-fits.

Figure 5

(A) Boxplots of the VOR (left column) and VVOR (right column) gains (top row) and phases (bottom row) across test frequencies for each group (Lesion group in white, BPPV in light gray, and Non-vestibular in dark gray). Each box begins at the first quartile, ends at the third quartile, denotes the median with a horizontal stripe and has whiskers denoting the maximum and minimum values. (B) VOR gain at 1 Hz for each participant vs. their age, clustered by group with group and overall line-fits.

Figure 6

Histogram of the minimum acceleration step time constant [across all directions and stimuli [left excitatory, left inhibitory, right excitatory, right inhibitory]] for each participant vs. their age, clustered by group with group and overall line-fits.