title: Risk factors for recurrence of benign paroxysmal positional vertigo.
abstract: OBJECTIVE
  To assess the results of treatment for a first episode of benign paroxysmal positional vertigo (BPPV) and risk factors for recurrence.
  
  
  METHODS
  Retrospective chart review of 148 BPPV patients at a tertiary care referral centre.
  
  
  METHODS
  The canalith repositioning procedure (CRP) was performed until vertigo and nystagmus were resolved. Using multivariate logistic regression, we estimated the relationship between the rate of BPPV recurrence within 1 year and various risk factors for BPPV.
  
  
  RESULTS
  Among the 145 patients after successful manoeuvre or spontaneous resolution, BPPV recurred in 31 patients (21%) within 1 year. Patients with recurrent BPPV in the posterior semicircular canal required more CRP sessions and a longer period. The rate of BPPV recurrence in patients with endolymphatic hydrops (75%) was significantly higher than in those without (odds ratio 17; 95% confidence interval 2.9-101). Both the first episode of BPPV and recurrent BPPV affected the same ear associated with endolymphatic hydrops in all patients with this complication.
  
  
  CONCLUSIONS
  Our data suggest that endolymphatic hydrops is a risk factor for recurrence of BPPV and that prevention of recurrent BPPV is important for control of endolymphatic hydrops.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tanimoto
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Doi
authors.forename: Tasuku
authors.initials: T
authors.lastname: Nishikawa
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Nibu
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D026201:Musculoskeletal Manipulations; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D016896:Treatment Outcome; D014717:Vertigo / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy*; D055815:Young Adult