Paving the Way Toward Distinguishing Fallers From Non-fallers in Bilateral Vestibulopathy: A Wide Pilot Observation

Abstract

Patients with bilateral vestibulopathy (BVP) present with unsteadiness during standing and walking, limiting their activities of daily life and, more importantly, resulting in an increased risk of falling. In BVP patients, falls are considered as one of the major complications, with patients having a 31-fold increased risk of falling compared to healthy subjects. Thus, highlighting objective measures that can easily and accurately assess the risk of falling in BVP patients is an important step in reducing the incidence of falls and the accompanying burdens. Therefore, this study investigated the interrelations between demographic characteristics, vestibular function, questionnaires on self-perceived handicap and balance confidence, clinical balance measures, gait variables, and fall status in 27 BVP patients. Based on the history of falls in the preceding 12 months, the patients were subdivided in a "faller" or "non-faller" group. Results on the different outcome measures were compared between the "faller" and "non-faller" subgroups using Pearson's chi-square test in the case of categorical data; for continuous data, Mann-Whitney U test was used. Performances on the clinical balance measures were comparable between fallers and non-fallers, indicating that, independent from fall status, the BVP patients present with an increased risk of falling. However, fallers tended to report a worse self-perceived handicap and confidence during performing activities of daily life. Spatiotemporal parameters of gait did not differ between fallers and non-fallers during walking at slow, preferred, or fast walking speed. These results may thus imply that, when aiming to distinguish fallers from non-fallers, the BVP patients' beliefs concerning their capabilities may be more important than the moderately or severely affected physical performance within a clinical setting. Outcome measures addressing the self-efficacy and fear of falling in BVP patients should therefore be incorporated in future research to investigate whether these are indeed able to distinguish fallers form non-fallers. Additionally, information regarding physical activity could provide valuable insights on the contextual information influencing behavior and falls in BVP.

Keywords: balance; bilateral vestibulopathy; falls; gait; self-perceived disability; vestibular function.

Figure 1

Graphical representation of the visual acuity loss during dynamic visual acuity testing on the treadmill in both fallers and non-fallers. The performances of fallers are indicated in red; the performances of non-fallers are indicated in blue. VAL, visual acuity loss. The p-values were calculated using Mann–Whitney U test; *p < 0.05. Number of subjects completing the DVA testing at 2 km/h: fallers: n = 11; non-fallers: n = 16; 4 km/h: fallers: n = 10; non-fallers: n = 14; 6 km/h: fallers: n = 8; non-fallers: n = 9. A decrease of ≥0.2 logMAR (i.e., VAL ≤ −0.2) is deemed abnormal at speeds of 2 and 4 km/h, while for 6 km/h, this is ≥0.3 logMAR (1, 21, 23).

Figure 2

Graphical representation of the performances of both fallers and non-fallers on the patient-reported outcome measures. The performances of fallers (n = 11) are indicated in red; the performances of non-fallers (n = 16) are indicated in blue. The p-values were calculated using Mann–Whitney U test. Dizziness Handicap Inventory: scores between 0 and 30 indicate a mild functional impairment, 31 to 60 indicate a moderate functional impairment, and 61 to 100 indicate a severe functional impairment (26). Activities-Specific Balance Confidence scale: a score above 80% indicates a high level of functioning, a score between 80 and 50% indicates a moderate level of functioning, and a score below 50% indicates a low level of functioning (28).

Figure 3

Graphical representation of the performances of both fallers and non-fallers on the clinical balance tests. The performances of fallers (n = 11) are indicated in red; the performances of non-fallers (n = 16) are indicated in blue. The p-values were calculated using Mann–Whitney U test. (1) Static balance sum—eyes closed: no cutoff values available. Five-Times-Sit-to-Stand: a cutoff of 13 s is indicative for a balance dysfunction in balance or vestibular disorders (31). (2) Timed Up and Go test: a score of ≥13.5 s is indicative for fall risk in patients with bilateral vestibulopathy post-rehabilitation (33). Timed Up and Go test with cognitive dual task: a score of ≥15 s is indicative for fall risk in an elderly population (32). (3) Timed Up and Go test with motor dual task: one faller and one non-faller were unable to perform the TUG-M due to their need for an assistive device. A score of ≥14.5 s is indicative for fall risk in an elderly population (32). Tinetti test: a score of ≥24/28 indicates a low risk of falls; 19–23/28: moderate risk of falls; ≤18/28: high risk of falls in an elderly population (34). (4) Functional gait assessment: A score of ≤ 22/30 is indicative for an increased fall risk in community-dwelling elderly (35).