title: Use of Scandinavian moist smokeless tobacco (snus) and the risk of atrial fibrillation.
abstract: BACKGROUND
  Snus is a smokeless tobacco product, widely used among Swedish men and increasingly so elsewhere. There is debate as to whether snus is an acceptable "harm-reduction" tobacco product. Since snus use delivers a dose of nicotine equivalent to cigarettes, and has been implicated in cardiac arrhythmia because of associations with sudden cardiovascular death, a relation with atrial fibrillation is plausible and important to investigate.
  
  
  METHODS
  To assess the relation between use of snus and risk of atrial fibrillation, we carried out a pooled analysis of 7 prospective Swedish cohort studies. In total, 274,882 men, recruited between 1978 and 2004, were followed via the National Patient Register for atrial fibrillation. Primary analyses were restricted to 127,907 never-smokers. Relative risks were estimated using Cox proportional hazard regression.
  
  
  RESULTS
  The prevalence of snus use was 25% among never-smokers. During follow-up, 3,069 cases of atrial fibrillation were identified. The pooled relative risk of atrial fibrillation was 1.07 (95% confidence interval = 0.97-1.19) in current snus users, compared with nonusers.
  
  
  CONCLUSIONS
  Findings from this large national pooling project indicate that snus use is unlikely to confer any important increase in risk of atrial fibrillation.
authors.affiliation: From the aDepartment of Communicable Disease Control, Stockholm County Council, Stockholm, Sweden; bDepartment of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden; cCentre for Epidemiology and Community Medicine, Stockholm County Council, Stockholm, Sweden; dInstitute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden; eDepartment of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; fDepartment of Statistics, University of Milano-Bicocca, Milano, Italy; gDepartment of Statistics, Umeå University, Umeå, Sweden; hSchool of Health Science, Jönköping University, Jönköping, Sweden; iDepartment of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden; jDepartment of Medicine, Umeå University, Umeå, Sweden; kDepartment of Health Sciences, Mid Sweden University, Sundsvall, Sweden; lUnit of Clinical Epidemiology, Dept of Medicine, Karolinska Institutet, Stockholm, Sweden; and mSocial Medicine and Global Health, Department of Clinical Sciences In Malmö, Lund University, Lund, Sweden.
authors.forename: Maria-Pia
authors.initials: MP
authors.lastname: Hergens
authors.forename: Rosaria
authors.initials: R
authors.lastname: Galanti
authors.forename: Jenny
authors.initials: J
authors.lastname: Hansson
authors.forename: Peeter
authors.initials: P
authors.lastname: Fredlund
authors.forename: Anders
authors.initials: A
authors.lastname: Ahlbom
authors.forename: Lars
authors.initials: L
authors.lastname: Alfredsson
authors.forename: Rino
authors.initials: R
authors.lastname: Bellocco
authors.forename: Marie
authors.initials: M
authors.lastname: Eriksson
authors.forename: Eleonor I
authors.initials: EI
authors.lastname: Fransson
authors.forename: Johan
authors.initials: J
authors.lastname: Hallqvist
authors.forename: Jan-Håkan
authors.initials: JH
authors.lastname: Jansson
authors.forename: Anders
authors.initials: A
authors.lastname: Knutsson
authors.forename: Nancy
authors.initials: N
authors.lastname: Pedersen
authors.forename: Ylva Trolle
authors.initials: YT
authors.lastname: Lagerros
authors.forename: Per-Olof
authors.initials: PO
authors.lastname: Ostergren
authors.forename: Cecilia
authors.initials: C
authors.lastname: Magnusson
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000139:chemically induced* / Q000453:epidemiology; D006801:Humans; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D012042:Registries; D012306:Risk; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D014030:Tobacco, Smokeless / Q000633:toxicity*