title: Personal history of gallstones and risk of incident psoriasis and psoriatic arthritis in U.S. women.
abstract: BACKGROUND
  Metabolic syndrome has been associated with both gallstones and psoriasis, suggesting a potential biological linkage between gallstones and psoriasis. However, the association between gallstones and psoriasis has not yet been studied.
  
  
  OBJECTIVE
  To investigate the association between gallstones and psoriasis.
  
  
  METHODS
  This was a prospective cohort study [Nurses' Health Study II (1991-2005)]. Women aged 25-42 years who were free from psoriasis at baseline and who responded to a 2005 follow-up questionnaire regarding their diagnosis of psoriasis were included (n = 89,230). The relative risk (RR) of developing psoriasis or psoriatic arthritis (PsA), which were self-reported and validated by supplemental questionnaires, was measured.
  
  
  RESULTS
  In this population, 2206 participants had gallstones confirmed by a history of cholecystectomy at baseline. A total of 642 individuals had a diagnosis of incident psoriasis, of whom 157 had concomitant PsA. After adjusting for known risk factors of psoriasis besides body mass index (BMI), a baseline history of cholecystectomy-confirmed gallstones was associated with increased risk of psoriasis [multivariate-adjusted RR 2·20, 95% confidence interval (CI) 1·56-3·10] and concomitant PsA (multivariate-adjusted RR 4·41, 95% CI 2·70-7·18). After additionally adjusting for BMI, the fully adjusted RRs associated with a history of cholecystectomy-confirmed gallstones were 1·70 (95% CI 1·20-2·41) for psoriasis and 2·96 (95% CI 1·80-4·89) for PsA.
  
  
  CONCLUSIONS
  Personal history of gallstones was associated with an increased risk of psoriasis and PsA, independent of obesity, in a cohort of U.S. women.
authors.affiliation: Department of Dermatology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, U.S.A.|Department of Health Policy and Management, Harvard School of Public Health, Boston, MA, U.S.A.
authors.forename: L X
authors.initials: LX
authors.lastname: Tong
authors.affiliation: Department of Dermatology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, U.S.A.|Department of Dermatology, Warren Alpert Medical School, Brown University, 339 Eddy Street, Providence, RI, 02903, U.S.A.
authors.forename: S
authors.initials: S
authors.lastname: Wu
authors.affiliation: Department of Dermatology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, U.S.A.|Department of Dermatology, Warren Alpert Medical School, Brown University, 339 Eddy Street, Providence, RI, 02903, U.S.A.
authors.forename: T
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Dermatology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, U.S.A.|Department of Dermatology, Warren Alpert Medical School, Brown University, 339 Eddy Street, Providence, RI, 02903, U.S.A.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, U.S.A.
authors.forename: A A
authors.initials: AA
authors.lastname: Qureshi
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, U.S.A.|Departments of Nutrition and Epidemiology, Harvard School of Public Health, Boston, MA, U.S.A.
authors.forename: E L
authors.initials: EL
authors.lastname: Giovannucci
authors.affiliation: Department of Dermatology, Warren Alpert Medical School, Brown University, 339 Eddy Street, Providence, RI, 02903, U.S.A.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, U.S.A.
authors.forename: E
authors.initials: E
authors.lastname: Cho
mesh_terms: D000328:Adult; D015535:Arthritis, Psoriatic / Q000453:epidemiology / Q000209:etiology*; D002763:Cholecystectomy / Q000706:statistics & numerical data; D004812:Epidemiologic Methods; D005260:Female; D042882:Gallstones / Q000150:complications* / Q000453:epidemiology / Q000601:surgery; D006801:Humans; D014481:United States / Q000453:epidemiology