title: Levels and determinants of inflammatory biomarkers in a Swiss population-based sample (CoLaus study).
abstract: OBJECTIVE
  to assess the levels and determinants of interleukin (IL)-1β, IL-6, tumour necrosis factor (TNF)-α and C-reactive protein (CRP) in a healthy Caucasian population.
  
  
  METHODS
  population sample of 2884 men and 3201 women aged 35 to 75. IL-1β, IL-6 and TNF-α were assessed by a multiplexed particle-based flow cytometric assay and CRP by an immunometric assay.
  
  
  RESULTS
  Spearman rank correlations between duplicate cytokine measurements (N = 80) ranged between 0.89 and 0.96; intra-class correlation coefficients ranged between 0.94 and 0.97, indicating good reproducibility. Among the 6085 participants, 2289 (37.6%), 451 (7.4%) and 43 (0.7%) had IL-1β, IL-6 and TNF-α levels below detection limits, respectively. Median (interquartile range) for participants with detectable values were 1.17 (0.48-3.90) pg/ml for IL-1β; 1.47 (0.71-3.53) pg/ml for IL-6; 2.89 (1.82-4.53) pg/ml for TNF-α and 1.3 (0.6-2.7) ng/ml for CRP. On multivariate analysis, greater age was the only factor inversely associated with IL-1β levels. Male sex, increased BMI and smoking were associated with greater IL-6 levels, while no relationship was found for age and leisure-time PA. Male sex, greater age, increased BMI and current smoking were associated with greater TNF-α levels, while no relationship was found with leisure-time PA. CRP levels were positively related to age, BMI and smoking, and inversely to male sex and physical activity.
  
  
  CONCLUSIONS
  Population-based levels of several cytokines were established. Increased age and BMI, and to a lesser degree sex and smoking, significantly and differentially impact cytokine levels, while leisure-time physical activity has little effect.
authors.affiliation: Institute of Social and Preventive Medicine, CHUV and Faculty of Biology and Medicine, Lausanne, Switzerland. Pedro-Manuel.Marques-Vidal@chuv.ch
authors.forename: Pedro
authors.initials: P
authors.lastname: Marques-Vidal
authors.forename: Murielle
authors.initials: M
authors.lastname: Bochud
authors.forename: François
authors.initials: F
authors.lastname: Bastardot
authors.forename: Thomas
authors.initials: T
authors.lastname: Lüscher
authors.forename: François
authors.initials: F
authors.lastname: Ferrero
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Gaspoz
authors.forename: Fred
authors.initials: F
authors.lastname: Paccaud
authors.forename: Adrian
authors.initials: A
authors.lastname: Urwyler
authors.forename: Roland
authors.initials: R
authors.lastname: von Känel
authors.forename: Christoph
authors.initials: C
authors.lastname: Hock
authors.forename: Gérard
authors.initials: G
authors.lastname: Waeber
authors.forename: Martin
authors.initials: M
authors.lastname: Preisig
authors.forename: Peter
authors.initials: P
authors.lastname: Vollenweider
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism*; D005260:Female; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D015203:Reproducibility of Results; D012307:Risk Factors; D013557:Switzerland
chemical_list: D015415:Biomarkers; D016207:Cytokines