RESUMEN
BACKGROUND/OBJECTIVE: Persistent postural-perceptual dizziness (PPPD) was defined by expert consensus for the forthcoming International Classification of Diseases, 11th edition. Its diagnostic criteria were derived from phobic postural vertigo and chronic subjective dizziness. Two key symptoms are postural unsteadiness and visually induced dizziness. We observed that patients with PPPD tended to perform poorly on multiple conditions of the EquiTest® Sensory Organization Test (SOT) and sought to investigate this phenomenon systematically. METHODS: We examined cross-sectional, pair-wise group differences in mean scores from SOT conditions 1-6 and composite scores among 20 patients with PPPD, 15 patients recovered from acute vestibular syndromes, and 15 normal individuals (all female, 43 ± 9 years old). We also compared proportions of patients in each group with abnormal sensory analyses, and poor performance across multiple conditions. RESULTS: Patients with PPPD had significantly lower mean scores than normal individuals on conditions 2-6 and the composite, and lower than recovered patients on conditions 2-3. Recovered patients had significantly lower mean scores than normal individuals on conditions 4-6 and the composite. Patients with PPPD had the greatest likelihood of abnormal sensory analyses. CONCLUSIONS: Patients with PPPD had difficulties with postural control across multiple sensory challenges, consistent with postulated neurophysiologic mechanisms of this condition.