title: No association between adherence to the healthy Nordic food index and cardiovascular disease amongst Swedish women: a cohort study.
abstract: BACKGROUND
  In several intervention trials, a healthy Nordic diet showed beneficial effects on markers of cardiovascular disease. We investigated the association between a healthy Nordic diet and clinical diagnosis of cardiovascular disease.
  
  
  OBJECTIVE
  Our aim was first to examine the association between a healthy Nordic food index (wholegrain bread, oatmeal, apples/pears, root vegetables, cabbages and fish) and the incidence of overall cardiovascular disease (ischaemic heart disease, stroke, arrhythmia, thrombosis and hypertensive disease), and secondly to test for possible effect modification by smoking, body mass index (BMI), alcohol consumption and age.
  
  
  METHODS
  We conducted an analysis of data from the prospective Swedish Women's Lifestyle and Health cohort, including 43 310 women who completed a food frequency questionnaire in 1991-1992, and followed up until 31 December 2012 through Swedish registries. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models.
  
  
  RESULTS
  During follow-up, 8383 women developed cardiovascular disease. We found no association between the healthy Nordic food index and overall cardiovascular disease risk or any of the subgroups investigated. There was a statistically significant interaction with smoking status (P = 0.02), with a beneficial effect only amongst former smokers (HR 0.96, 95% CI 0.94-0.99 per 1-point increment).
  
  
  CONCLUSIONS
  The present results do not support an association between a healthy Nordic food index and risk of cardiovascular disease in Swedish women. There was also no effect modification by alcohol intake, BMI or age. Our finding of an interaction with smoking status requires reproduction.
authors.affiliation: Danish Cancer Society Research Center, Copenhagen, Denmark.|Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: N
authors.initials: N
authors.lastname: Roswall
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Sandin
authors.affiliation: School of Population Health, University of Auckland, Auckland, New Zealand.
authors.forename: R
authors.initials: R
authors.lastname: Scragg
authors.affiliation: Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Löf
authors.affiliation: Department of Community Medicine, University of Tromsö, The Arctic University of Norway, Tromsö, Norway.
authors.forename: G
authors.initials: G
authors.lastname: Skeie
authors.affiliation: Danish Cancer Society Research Center, Copenhagen, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Olsen
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.|Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA.
authors.forename: H-O
authors.initials: HO
authors.lastname: Adami
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.|Department of Community Medicine, University of Tromsö, The Arctic University of Norway, Tromsö, Norway.|Genetic Epidemiology Group, Folkhälsan Research Center, Helsinki, Finland.|The Cancer Registry of Norway, Oslo, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Weiderpass
mesh_terms: D000328:Adult; D000367:Age Factors; D000428:Alcohol Drinking / Q000453:epidemiology*; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000517:prevention & control; D004035:Diet Therapy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008019:Life Style; D008875:Middle Aged; D010349:Patient Compliance / Q000706:statistics & numerical data*; D011446:Prospective Studies; D012307:Risk Factors; D040242:Risk Reduction Behavior; D012907:Smoking / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology
keywords: Nordic diet; cardiovascular disease; cohort study; ischaemic heart disease; stroke