Psychological Factors Associated With Discrepancies Between Subjective Balance Confidence and Objective Performance of Patients With Unilateral Vestibular Hypofunction

OBJECTIVE: Discrepancies between subjective balance confidence and objective performance may have clinical consequences in patients with vestibular hypofunction. Overestimation may increase fall risks, whereas underestimation may lead to unnecessary activity restriction. The contributing factors remain unclear. STUDY DESIGN: Observational study. SETTING: A primary care outpatient clinic. PATIENTS: This study included 160 patients with unilateral vestibular hypofunction. MAIN OUTCOME MEASURES: The subjective-objective balance discrepancy was quantified using z-score standardization of the Activities-specific Balance Confidence Scale and Functional Gait Assessment (Z_ABC-Z_FGA). Associations between dizziness-related disability, anxiety, and depression (Hospital Anxiety and Depression Scale, HADS) were examined using hierarchical regression with interaction terms. RESULTS: Overestimation was observed in 54.4% of patients; the remaining 45.6% underestimated it. The overestimation group showed lower dizziness-related disability than the underestimation group (33.6±21.0 vs. 45.8±22.0, P=0.001). Dizziness-related disability was independently associated with discrepancy scores (β=-0.327, P<0.001). In exploratory analyses using the dichotomized clinical HADS classification, anxiety (β=-0.315, P<0.001) and depression (β=-0.224, P=0.010) were associated with greater underestimation, attenuated in the overestimation group. These associations were only partly reproduced with continuous HADS scores. CONCLUSIONS: Anxiety and depression were associated with the discrepancy, mainly in patients who underestimated their balance ability, whereas dizziness-related disability was independently associated with it. These findings suggest that psychological distress relates to negative self-evaluation of balance and should be considered alongside performance-based measures when interpreting self-reported balance confidence in vestibular rehabilitation.