title: Smoking tobacco, oral snuff, and alcohol in the etiology of squamous cell carcinoma of the head and neck: a population-based case-referent study in Sweden.
abstract: BACKGROUND
  This case-referent study was conducted to elucidate the role of selected exogenous agents in the etiology of head and neck cancer. The factors studied were tobacco smoking, alcohol intake, the use of moist oral snuff, dietary factors, occupational exposures, and oral hygiene. In this first report, the authors discuss the impact of tobacco smoking, the use of oral snuff, and alcohol consumption.
  
  
  METHODS
  The study base was approximately 2 million person-years at risk and consisted of Swedish males age 40-79 years living in 2 geographic regions during the years 1988-1990. A total of 605 cases were identified in the base, and 756 controls were selected by stratified random sampling from population registries covering the base.
  
  
  RESULTS
  Among those who were tobacco smokers at the time of the study, the relative risk of head and neck cancer was 6.5% (95% confidence interval, 4.4-9.5%). After cessation of smoking, the risk gradually declined, and no excess risk was found after 20 years. The relative risk associated with alcohol consumption of 50 grams or more per day versus less than 10 grams per day was 5.5% (95% confidence interval, 3.1-9.6%). An almost multiplicative effect was found for tobacco smoking and alcohol consumption.
  
  
  CONCLUSIONS
  Tobacco smoking and alcohol intake had a strong interactive effect on the risk of squamous cell carcinoma of the head and neck. Moderate alcohol intake (10-19 grams per day) had little or no effect among nonsmokers. No increased risk was found for the use of Swedish oral snuff.
authors.affiliation: Oncologic Centre, Karolinska Hospital, Stockholm, Sweden.
authors.forename: F
authors.initials: F
authors.lastname: Lewin
authors.forename: S E
authors.initials: SE
authors.lastname: Norell
authors.forename: H
authors.initials: H
authors.lastname: Johansson
authors.forename: P
authors.initials: P
authors.lastname: Gustavsson
authors.forename: J
authors.initials: J
authors.lastname: Wennerberg
authors.forename: A
authors.initials: A
authors.lastname: Biörklund
authors.forename: L E
authors.initials: LE
authors.lastname: Rutqvist
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000009:adverse effects*; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000209:etiology*; D006258:Head and Neck Neoplasms / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010947:Plants, Toxic; D012306:Risk; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D013548:Sweden / Q000453:epidemiology; D014030:Tobacco, Smokeless / Q000009:adverse effects*