title: A case-control study of the risk factors associated with sinonasal inverted papilloma.
abstract: BACKGROUND
  The etiology of sinonasal inverted papilloma (IP) is unknown. This study was designed to evaluate the possible risk factors associated with IP Methods: This is a case-control epidemiology study in a tertiary referral center. Fifty patients with IP and 150 matched controls were interviewed using a questionnaire on suspected risk factors. Univariate analysis of the risk factors and calculation of the matched odds ratios, the corresponding 95% CIs, and p values was performed. Significant risk factors were further studied using conditional logistic regression analysis.
  
  
  RESULTS
  Outdoor and industrial occupations were associated with IP. Tobacco smoking, drinking alcohol, history of allergic rhinitis, sinusitis, nasal polyp, non-sinonasal papilloma and non-sinonasal malignancy were not significant factors.
  
  
  CONCLUSIONS
  Outdoor and industrial occupations were associated with IP and may be potential risk factors. Future studies are warranted to further evaluate the individual type of occupation and chemical involved.
authors.affiliation: Department of Otorhinolaryngology, Head and Neck Surgery, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Cheuk Lun
authors.initials: CL
authors.lastname: Sham
authors.forename: Dennis L Y
authors.initials: DL
authors.lastname: Lee
authors.forename: C Andrew
authors.initials: CA
authors.lastname: van Hasselt
authors.forename: Michael C F
authors.initials: MC
authors.lastname: Tong
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009669:Nose Neoplasms / Q000453:epidemiology* / Q000473:pathology / Q000503:physiopathology; D016273:Occupational Exposure; D018308:Papilloma, Inverted / Q000453:epidemiology* / Q000473:pathology / Q000503:physiopathology; D010256:Paranasal Sinuses / Q000473:pathology*; D012307:Risk Factors; D012907:Smoking