title: Fruit and vegetable consumption and risk of cholecystectomy: a prospective cohort study of women and men.
abstract: OBJECTIVE
  Epidemiologic data on whether consumption of fruit and vegetables (FVs) decreases the risk of gallstone disease are sparse. Therefore, we examined the association between FV consumption and the 14-year risk of symptomatic gallstone disease (defined as occurrence of cholecystectomy) in a large group of middle-aged and elderly persons.
  
  
  METHODS
  Data from two population-based cohorts were used, which included 74,554 men and women (born 1914-1952). Participants filled in a food frequency questionnaire in the late fall of 1997 and were followed up for cholecystectomy between 1998 and 2011 via linkage to the Swedish Patient Register. Cox regression models were used to obtain hazard ratios (HRs).
  
  
  RESULTS
  During 939,715 person-years of follow-up, 2120 participants underwent a cholecystectomy (1120 women and 1000 men). An inverse association between FV consumption and risk of cholecystectomy was observed in age- and sex-adjusted analyses (Ptrend= .036) but not in confounder-adjusted analyses (Ptrend= .43). The multivariable-adjusted HR was 0.95 (95 % CI 0.83-1.08) for the highest compared with the lowest sex-specific quartile of FV consumption. There was no evidence of interactions with age (P = .25) or sex (P = .72) in analyses pooled by sex. However, an age-by-FV consumption interaction was observed in separate analyses of women (P = .010), with decreased HRs of cholecystectomy for ages up to 60 years.
  
  
  CONCLUSIONS
  This study supports an inverse association between FV consumption and risk cholecystectomy in women, although the association was restricted to women aged 48-60 years. In contrast, the study does not support an association in men.
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, 171 76, Sweden. caroline.nordenvall@ki.se.|Center for Digestive Diseases, Department of Coloproctology, Karolinska University Hospital, 171 76, Stockholm, Sweden. caroline.nordenvall@ki.se.
authors.forename: Caroline
authors.initials: C
authors.lastname: Nordenvall
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
authors.forename: Viktor
authors.initials: V
authors.lastname: Oskarsson
authors.affiliation: Institute of Environmental Medicine, Karolinska Institutet, 171 77, Stockholm, Sweden.
authors.forename: Alicja
authors.initials: A
authors.lastname: Wolk
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002763:Cholecystectomy / Q000706:statistics & numerical data*; D015331:Cohort Studies; D004032:Diet; D005260:Female; D005638:Fruit; D042882:Gallstones / Q000453:epidemiology* / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012737:Sex Factors; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology; D014675:Vegetables
keywords: Cohort study; Fruit consumption; Gallbladder disease; Vegetable consumption