title: C-reactive protein and postmenopausal breast cancer risk: results from the E3N cohort study.
abstract: BACKGROUND
  C-reactive protein (CRP), a marker of low-grade inflammation, has been associated with breast cancer risk, but results are scarce and inconsistent.
  
  
  METHODS
  A case-control study nested within the E3N prospective cohort included 549 postmenopausal breast cancer cases and 1,040 matched controls, all free of breast cancer at baseline. Serum levels of CRP were measured in samples collected between 1995 and 1999. Unconditional logistic regression models were used to evaluate the association between CRP and breast cancer risk, adjusting for matching factors and known breast cancer risk factors.
  
  
  RESULTS
  No association was observed between CRP levels and breast cancer risk overall. However, a significant interaction was observed between CRP levels and body mass index (BMI). A statistically significant increase in breast cancer risk was observed in overweight and obese women (BMI ≥ 25 kg/m(2)) (OR 1.92, 95 % CI 1.20-3.08 for CRP ≥ 2.5 mg/L compared with CRP < 1.5 mg/l, p trend = 0.003, p interaction between CRP and BMI = 0.03). Similar results were observed in women with waist circumference (WC) ≥ 88 cm (p trend = 0.01, p interaction = 0.06) and waist-to-hip ratio (WHR) ≥ 0.80 (p trend = 0.06, p interaction = 0.35). CRP levels were not associated with breast cancer risk in women with normal BMI, WC, or WHR.
  
  
  CONCLUSIONS
  We found a positive association between CRP levels and postmenopausal breast cancer risk restricted to women with excess adiposity. The suggested relationship between low-grade inflammation, abdominal adiposity, and postmenopausal breast cancer risk deserves further investigation.
authors: Team 9: Nutrition, Hormones and Women's Health, Center for Research in Epidemiology and Population Health, Institut National de la Santé et de la Recherche Médicale (INSERM) U1018, Institut Gustave Roussy, 114 Rue Edouard Vaillant, 94805, Villejuif Cedex, France.
authors: Laure
authors: L
authors: Dossus
authors: Aida
authors: A
authors: Jimenez-Corona
authors: Isabelle
authors: I
authors: Romieu
authors: Marie-Christine
authors: MC
authors: Boutron-Ruault
authors: Anne
authors: A
authors: Boutten
authors: Thierry
authors: T
authors: Dupré
authors: Guy
authors: G
authors: Fagherazzi
authors: Francoise
authors: F
authors: Clavel-Chapelon
authors: Sylvie
authors: S
authors: Mesrine
mesh_terms: D001943:Breast Neoplasms / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism*; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood*; D011446:Prospective Studies; D011795:Surveys and Questionnaires
chemical_list: D002097:C-Reactive Protein