Dizziness handicap and clinical characteristics of posterior and lateral canal BPPV.

PURPOSE

Benign paroxysmal positional vertigo (BPPV) is diagnosed and divided into subtypes based on positioning vertigo and nystagmus. Whether these subtypes entail any significant differences in patient-reported symptoms; is yet not known. Such differences may have clinical and therapeutic consequences. Our aim was to assess dizziness handicap and clinical characteristics of posterior and lateral canal BPPV.

METHODS

This prospective observational multicentre study analysed consecutive patients with BPPV, confirmed by standardized procedures including videonystagmography under diagnostic manoeuvres in a biaxial rotational chair. Patients were screened for other neurological and otological disorders.

OUTCOMES

Dizziness handicap inventory (DHI), posterior vs. lateral canal involvement.

FACTORS

age, gender, positional nystagmus intensity (maximum slow-phase velocity), symptom duration, 25-hydroxyvitamin D-level and traumatic aetiology.

RESULTS

132 patients aged 27-90 (mean 57, SD 13) years were included. Higher DHI scores were associated with lateral canal BPPV [95% CI (1.59-13.95), p = 0.01] and female gender [95% CI (0.74-15.52), p = 0.03]. Lateral canal BPPV was associated with longer symptom duration [OR 1.10, CI (1.03-1.17), p = 0.01] and lower 25-hydroxyvitamin D-levels [OR 0.80, CI (0.67-0.95), p = 0.03]. There was no correlation between DHI scores and nystagmus intensity.

CONCLUSIONS

This study suggests that patients with lateral canal BPPV have increased patient-perceived disability, lower vitamin D-levels and longer duration of symptoms. This subtype might therefore require closer follow-up. Patient-perceived disability is not related to positional nystagmus intensity.