A Validated Questionnaire to Assess the Severity of Persistent Postural-Perceptual Dizziness (PPPD): The Niigata PPPD Questionnaire (NPQ)

Abstract

Objective: To establish a questionnaire to diagnose and assess the severity of persistent postural-perceptual dizziness (PPPD). Study Design: Retrospective chart review. Setting: Tertiary referral center. Patients: Fifty PPPD patients and 50 consecutive control patients with other vestibular disorders. Interventions: Patients answered questions on three exacerbating factors of PPPD (upright posture/walking, movement, and visual stimulation), and each factor was evaluated using four questions scoring the severity from 0 (none) to 6 (unbearable). Somatic and psychological distress was evaluated by the Visual Analog Scale (VAS) and the Hospital Anxiety and Depression Scale (HADS), respectively. Main Outcome Measures: The questionnaire's reliability was tested by Cronbach's alpha, and it was validated by examining the differences in the questionnaire's scores between PPPD patients and controls. The area under the curve (AUC) of the receiver operating characteristic curve for each factor was calculated. Results: Cronbach's alpha coefficient was >0.8 for all factors, except the movement factor. There were no significant differences in the VAS and HADS scores between the two groups. However, the combined and individual questionnaire scores for each factor were higher in PPPD patients than in controls, indicating the questionnaire's high validity. The AUC was widest for the visual stimulation factor (0.830), and a score of 9 (full score 24) had the best sensitivity (82%) and specificity (74%) for discriminating PPPD patients from controls. Conclusions: We developed a questionnaire that exhibited high reliability and validity in evaluating PPPD severity. The visual stimulation factor may be the most characteristic among the three exacerbating factors.

Assessment of Potential Risk Factors for the Development of Persistent Postural-Perceptual Dizziness: A Case-Control Pilot Study

“…Anxiety and anxiety-related personality traits, in particular neuroticism, have been described as possible predisposing factors, making the affected individual prone to a hypervigilant state of increased introspective selfmonitoring that arises from fear of further attacks of vertigo or the consequences of being dizzy during or following the episode of acute vestibular disease (7,10,11,(18)(19)(20)(21)(22)(23)(24)(25). Yagi et al (26) have recently developed a PPPD severity questionnaire (the Niigata PPPD Questionnaire) that reflects the diagnostic criteria of PPPD (26). Even more recently, Powell et al (27) describe PPPD as a complex neurological condition that includes broad perceptual factors and suggest that some individuals' brains are predisposed to generalized cross-modal sensory-overload, giving rise to vulnerability to severe PPPD should a vestibular insult occur (27).…”

The Clinical Key Features of Persistent Postural Perceptual Dizziness in the General Medicine Outpatient Setting: A Case Series Study of 33 Patients

“…In the preceding episode of acute dizziness, BPPV was the most common in this study (81.8%) while vestibular neuritis was most common in the previous reports (39.3% as reported by Adamec et al and 38.0% as reported by Yagi et al). 7,8 Because vestibular neuritis has a younger age of onset compared to BPPV, 9,10 the median age of patients with PPPD in this study may have been higher. In addition, the prognosis of PPPD may be worse if BPPV precedes PPPD because BPPV recurs more frequently than vestibular neuritis.…”

“…In terms of age, the median age in this study was older than that in the report, 61 years of age (range: 26-87) ( 7 ). In addition, the mean age in the previous report by Yagi et al in Japan was 50 years of age (range: 25-79) ( 8 ). In the preceding episode of acute dizziness, BPPV was the most common in this study (81.8%) while vestibular neuritis was most common in the previous reports (39.3% as reported by Adamec et al and 38.0% as reported by Yagi et al) ( 7 , 8 ).…”

“…In addition, the mean age in the previous report by Yagi et al in Japan was 50 years of age (range: 25-79) ( 8 ). In the preceding episode of acute dizziness, BPPV was the most common in this study (81.8%) while vestibular neuritis was most common in the previous reports (39.3% as reported by Adamec et al and 38.0% as reported by Yagi et al) ( 7 , 8 ). Because vestibular neuritis has a younger age of onset compared to BPPV ( 9 , 10 ), the median age of patients with PPPD in this study may have been higher.…”

“…Active or passive motion without regard to direction or position is an exacerbating factor for PPPD in 90.9% of patients, a high percentage. The triggering of symptoms by exposure to moving visual stimuli or complex visual patterns is reported to be a highly specific exacerbating factor that differentiates PPPD from other disorders ( 8 ). Although only 15.2% of patients in this study experienced all three factors as exacerbating factors, symptoms were triggered by active or passive motion without regard to direction or position in 90.9% of cases, making this an important factor for PPPD screening.…”