title: Correlation between the head-lying side during sleep and the affected side by benign paroxysmal positional vertigo involving the posterior or horizontal semicircular canal.
abstract: OBJECTIVE
  The aim of this study was to evaluate the relationship between the head position during sleep and the affected semicircular canal (SCC) in patients with benign paroxysmal positional vertigo (BPPV).
  
  
  METHODS
  Prospective study at a tertiary hospital.
  
  
  METHODS
  We conducted a prospective study in patients with BPPV involving posterior or horizontal SCCs. Of a total of 425 patients diagnosed with BPPV, 83 patients showing signs of simultaneous multiple canal involvement, and those having combined otologic diseases in the same ear were excluded from the study. All patients included in the study were asked to define their preferred head-lying side at the beginning of sleep among the following choices: supine, lateral (right or left), or no predominant side.
  
  
  RESULTS
  Our study included 174 patients with posterior SCC BPPV (p-BPPV) and 168 patients with horizontal SCC BPPV (h-BPPV). Patients habitually adopted a lateral head position during sleep in 105 cases of p-BPPV and 109 cases of h-BPPV. Statistically significant correlation was demonstrated between the head-lying side during sleep and the affected side by BPPV (P < .01) in patients with p-BPPV as well as h-BPPV.
  
  
  CONCLUSIONS
  There is significant correlation between the head-lying side during sleep and the side affected by BPPV in h-BPPV and p-BPPV, which may provide additional clues about the pathophysiology of BPPV. Clinically, this information may be used to provide helpful guidelines for patients with BPPV concerning their sleeping positions to prevent recurrence of BPPV.
authors.affiliation: Department of Otorhinolaryngology, Myongji Hospital, Kwandong University College of Medicine, Goyang, South Korea.
authors.forename: Dae Bo
authors.initials: DB
authors.lastname: Shim
authors.forename: Ji Hong
authors.initials: JH
authors.lastname: Kim
authors.forename: Kye Chun
authors.initials: KC
authors.lastname: Park
authors.forename: Mee Hyun
authors.initials: MH
authors.lastname: Song
authors.forename: Hong Ju
authors.initials: HJ
authors.lastname: Park
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D065635:Benign Paroxysmal Positional Vertigo; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D019416:Head Movements; D006801:Humans; D008297:Male; D008875:Middle Aged; D011187:Posture / Q000502:physiology*; D011446:Prospective Studies; D012665:Semicircular Canals / Q000503:physiopathology*; D012890:Sleep / Q000502:physiology*; D014717:Vertigo / Q000175:diagnosis* / Q000503:physiopathology; D055815:Young Adult