title: [C-Reactive protein levels in patients with chronic obstructive pulmonary disease].
abstract: BACKGROUND
  Patients with chronic obstructive pulmonary disease (COPD) have elevated serum levels of ultrasensitive C reactive protein (CRPus). This raise may be related directly to COPD and its associated systemic inflammation or secondary to other factors such as smoking status, disease severity, acute exacerbations, or associated complications.
  
  
  OBJECTIVE
  To evaluate the potential causes of raised levels of CRPus in stable COPD patients.
  
  
  METHODS
  Cohorts of 133 mild-to-very severe COPD patients (41 current smokers), 31 never-smokers, and 33 current smoker controls were compared. Clinical assessments included body mass index (BMI), fat (FM) and fat-free mass (FFM) measurement by DEXA, forced expiratory volume in one second (FEV1), arterial oxygen tension (PaO2), six-minute walking test (SMWT), emphysema (EMPH) and right thigh muscle cross-sectional area (TMCSA), both quantified by high resolution computed tomography.
  
  
  RESULTS
  Serum CRPus levels were significantly higher in COPD patients than in controls (7 ± 4.2 and 3.7 ± 2.7 mg/L respectively; p < 0.0001). Being smoker did not influence CRPus levels. These levels were significantly correlated with FM (r = 0.30), BMI (r = 0.21), FEV1 (r = -0.21), number of acute exacerbations of the disease in the last year (r = 0.28), and PaO2 (r = -0.27). Using multivariate analysis FM, PaO2, and number of acute exacerbations of the disease in the last year had the strongest association with CRPus levels.
  
  
  CONCLUSIONS
  CRPus is elevated in COPD patients, independent of smoking status. It is weakly associated with fat mass, arterial oxygen tension and frequency of exacerbations.
authors.affiliation: Departamento de Enfermedades Respiratorias, Pontificia Universidad Católica de Chile, Chile. odiazp@vtr.net
authors.forename: Orlando
authors.initials: O
authors.lastname: Díaz
authors.forename: Alejandra
authors.initials: A
authors.lastname: Parada
authors.forename: Critóbal
authors.initials: C
authors.lastname: Ramos
authors.forename: Julieta
authors.initials: J
authors.lastname: Klaassen
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Díaz
authors.forename: Max
authors.initials: M
authors.lastname: Andresen
authors.forename: Carmen
authors.initials: C
authors.lastname: Lisboa
authors.forename: Fernando
authors.initials: F
authors.lastname: Saldías
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis*; D016022:Case-Control Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007249:Inflammation / Q000097:blood; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000097:blood* / Q000503:physiopathology; D012907:Smoking / Q000009:adverse effects*; D018746:Systemic Inflammatory Response Syndrome / Q000097:blood* / Q000503:physiopathology
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein