title: Clinical features of recurrence and osteoporotic changes in benign paroxysmal positional vertigo.
abstract: OBJECTIVE
  Several previous studies have demonstrated that comorbidities, secondary causes, physical inactivity, and osteoporosis may cause recurrence of benign paroxysmal positional vertigo (BPPV). However, there has also been some controversy over the clinical course(s) and cause(s) of recurrent BPPV (rBPPV). We identified clinical features and associated factors, including decreased bone mineral density, in the recurrence of BPPV.
  
  
  METHODS
  In total, 198 patients with idiopathic BPPV, diagnosed at the otolaryngology clinics of Seoul National University Boramae Medical Center, were enrolled. The medical data of these patients were reviewed retrospectively. Recurrent BPPV was defined as the recurrence of BPPV after at least 1 month of a symptom-free interval following previous successful treatment.
  
  
  RESULTS
  Of the BPPV patients, 67 (33.8%) were classified as rBPPV. Among them, about 16% showed changes in the involved semicircular canals and about 6% showed multiple semicircular canal involvement. rBPPV was more common in patients with comorbidities (P<0.001). Involved semicircular canals showed no statistically significant difference according to the recurrence of BPPV. The mean symptom-free interval of the rBPPV group varied from 1 to 50.2 (mean, 11.6) months; however, 90% of BPPV recurrence occurred within 24 months. Bone mineral density in dual-energy X-ray absorptiometry (DEXA) was markedly decreased in BPPV patients versus normal controls, but there were no significant differences according to BPPV recurrence.
  
  
  CONCLUSIONS
  The incidence of rBPPV in idiopathic BPPV patients was 33.8% in the present study. The mean period of recurrence after a symptom-free interval was about 11.6 months; most patients showed recurrence within 2 years after the first attack of BPPV. Furthermore, about 16% of patients suffered from rBPPV at a different kind or type of canal from the semicircular canal of the initial BPPV attack. Comorbidities, but not age, gender, or the involved semicircular canal, might be correlated with BPPV recurrence. Decreased bone mineral density did not show significant association with BPPV recurrence, but showed a significant relation with BPPV occurrence.
authors.affiliation: Department of Otorhinolaryngology, Bundang CHA Medical Center, CHA University, Seongnam, Republic of Korea.
authors.forename: So Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology, Boramae Medical Center, Seoul Metropolitan Government-Seoul National University, Seoul, Republic of Korea.
authors.forename: Seung Hoon
authors.initials: SH
authors.lastname: Han
authors.affiliation: Department of Otorhinolaryngology, Boramae Medical Center, Seoul Metropolitan Government-Seoul National University, Seoul, Republic of Korea.
authors.forename: Young Ho
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Otorhinolaryngology, Boramae Medical Center, Seoul Metropolitan Government-Seoul National University, Seoul, Republic of Korea. Electronic address: drpark@snu.ac.kr.
authors.forename: Min-Hyun
authors.initials: MH
authors.lastname: Park
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D065635:Benign Paroxysmal Positional Vertigo / Q000453:epidemiology* / Q000503:physiopathology; D015897:Comorbidity; D003920:Diabetes Mellitus / Q000453:epidemiology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D012008:Recurrence; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012665:Semicircular Canals / Q000503:physiopathology
keywords: Benign paroxysmal positional vertigo; Bone mineral density; Recurrence; Semicircular canal