A comparison of dizziness handicap inventory scores by categories of vestibular diagnoses

Objective: The Dizziness Handicap Inventory (DHI) is a 25- item self-report quantifying dizziness-related physical and emotional symptoms and restrictions in daily activities. DHI scores do not correlate with severity of structural vestibular deficits; thus, high DHI scores may reflect other causes of morbidity. This study investigated the relationship between total DHI scores and the presence of structural, functional, and psychiatric disorders in tertiary neurotology patients. Study Design: Retrospective. Setting: Tertiary center. Patients: Eighty-five patients who underwent multidisciplinary neurotologic evaluations. Intervention: Diagnostic. Main Outcome Measure(s): Active illnesses identified by a multidisciplinary neurotology team were abstracted from medical records, cataloged as structural, functional, or psychiatric disorders, and used to group patients into diagnostic categories: structural (structural disorders only), functional (functional disorders with/without structural disorders), and psychiatric (psychiatric disorders with/without other conditions). DHI scores were compared across diagnostic categories. Sensitivities and specificities of DHI scores for identifying structural versus functional or psychiatric disorders were calculated. Results: Mean DHI scores differed significantly by diagnostic category (structural 35±18, functional 64±15, and psychiatric 65±19), before and after adjusting for age and sex ( p<0.001, Hedges' g>1.62 for structural versus functional and psychiatric categories). DHI≤30 (mild handicap) had specificity=0.98 for structural disorders alone, whereas DHI>60 (severe handicap) had specificity=0.88 for functional or psychiatric disorders. Conclusions: In this tertiary cohort, categories of illnesses had large effects on total DHI scores. Patients with scores ≤30 were likely to have structural disorders alone, whereas those with scores >60 were likely to have functional or psychiatric disorders, with or without coexisting structural conditions.