title: Factors related to primary bilateral spontaneous pneumothorax.
abstract: OBJECTIVE
  We studied the risk factors associated with primary bilateral spontaneous pneumothorax.
  
  
  METHODS
  From January 2001 to December 2002, 102 patients with primary spontaneous pneumothorax were reviewed and divided into two groups. Group A patients had primary spontaneous bilateral pneumothorax (PSBP; simultaneous or nonsimultaneous). Group B included patients with a primary spontaneous pneumothorax (PSP). We compared age, smoking habits, body weight, height, body mass index (BMI), and radiological findings between groups.
  
  
  RESULTS
  Twenty-four patients developed PSBP (24 %). The male-to-female ratio was 22 : 2 in group A and 73 : 5 in group B ( P = 0.106). Eleven group A patients (46 %) and 34 group B patients (44 %) were smokers ( P = 0.037). The mean BMI was 18.39 +/- 2.45 kg/m (2) in group A and 19.70 +/- 2.00 kg/m (2) in group B ( P = 0.009). High-resolution computed tomography revealed bilateral lung blebs or bullae in 63 % of group A patients and in 53 % of group B patients ( P = 0.724).
  
  
  CONCLUSIONS
  PSBP was significantly more frequent in patients with a lower BMI and among smokers. These patients require extended hospitalization and vigilant treatment.
authors.affiliation: Division of Thoracic, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: T-W
authors.initials: TW
authors.lastname: Huang
authors.forename: Y-L
authors.initials: YL
authors.lastname: Cheng
authors.forename: C
authors.initials: C
authors.lastname: Tzao
authors.forename: C
authors.initials: C
authors.lastname: Hung
authors.forename: H-H
authors.initials: HH
authors.lastname: Hsu
authors.forename: J-C
authors.initials: JC
authors.lastname: Chen
authors.forename: S-C
authors.initials: SC
authors.lastname: Lee
mesh_terms: D000328:Adult; D001827:Body Height; D015992:Body Mass Index; D005260:Female; D006801:Humans; D008297:Male; D011030:Pneumothorax / Q000453:epidemiology* / Q000601:surgery; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology