Vestibular deficits and psychological factors correlating to dizziness handicap and symptom severity

Objective: To determine the relative contribution of demographic variables, objective testing and psychological factors in explaining the variance in dizziness severity and handicap. Methods: One-hundred and eighty-five consecutive patients on the waiting list to attend a diagnostic appointment in a tertiary neuro-otology clinic with a primary complaint of vertigo or dizziness completed a cross-sectional survey. Primary outcomes were the Dizziness Handicap Inventory and the vertigo subscale of the Vertigo Symptom Scale-Short Form. Psychological questionnaires assessed anxiety and depressive symptoms, illness perceptions, cognitive and behavioural responses to symptoms, beliefs about emotions and psychological vulnerability. Patients also underwent standardised audio-vestibular investigations and tests to reach a diagnosis at appointment. Results: Objective disease characteristics were not associated with handicap and only the presence of vestibular dysfunction on one test (caloric) was associated with symptom severity. Almost all the psychological factors were correlated with dizziness outcomes. The total hierarchical regression model explained 63% of the variance in dizziness handicap, and 53% was explained by the psychological variables. The regression model for symptom severity explained 36% of the variance, and 30% was explained by the psychological factors. In adjusted models, factors associated with dizziness handicap included age, female gender, distress, symptom focusing, embarrassment, avoidance, and beliefs about negative consequences. Fear avoidance was the only independent correlate in the fully adjusted model of symptom severity. Conclusion: Self-reported dizziness severity and handicap are not correlated with clinical tests of vestibular deficits but are associated with psychological factors including anxiety, depression, illness perceptions, cognitive and behavioural responses.