title: Predictive value of C-reactive protein and clinically relevant baseline variables in sarcoidosis.
abstract: BACKGROUND
  This study aims to examine the predictive and prognostic implications of C-reactive protein (CRP) and clinically relevant baseline variables in determining treatment indication and disease progression in a large clinical cohort of patients with stable sarcoidosis.
  
  
  METHODS
  A retrospective observational study of 328 sarcoidosis patients attending a regional tertiary referral centre over a 26-year period was performed. Clinical, biochemical, radiological and physiological data were analysed according to a clinically relevant dichotomous cutpoint of CRP. Multiple models of logistic regression were used to determine independent predictors of outcome as defined by indication for treatment with corticosteroids, radiological deterioration and physiological progression.
  
  
  RESULTS
  328/409 (80.2%) sarcoidosis patients had baseline serum CRP measured and were suitable for inclusion. Baseline CRP was elevated in 154 (47%). 178 (54.3%) were prescribed corticosteroid treatment during the disease course. Physiological deterioration was demonstrated in 48 (14.6%) patients and radiological progression in 59 (17.9%) patients. High baseline CRP was strongly associated with Lofgren's syndrome (p=<0.001) and reduced FVC% predicted (p=0.012). High CRP was found to be a negative predictor of radiological progression (p=0.046). In a sub-analyses of patients without Lofgren's syndrome (n=223), patients with high baseline CRP were almost twice as likely to receive corticosteroid treatment, OR 1.89 (95% CI 1.04-3.55). Low baseline DLCO% independently predicted the need for corticosteroid treatment (p=<0.001) and physiological decline (p=0.045).
  
  
  CONCLUSIONS
  Elevated baseline CRP in sarcoidosis is associated with a good prognosis and is a negative predictive indicator of radiological progression. In patients without Lofgren's syndrome, high CRP and low DLCO% at presentation may identify a subset of patients more likely to develop physiological progression who may benefit from early systemic treatment.
authors.affiliation: Galway University Hospitals, Newcastle Road, Galway, Ireland. melissajanefriel@gmail.com.
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: McDonnell
authors.forename: Mohammed I
authors.initials: MI
authors.lastname: Saleem
authors.forename: Deidre
authors.initials: D
authors.lastname: Wall
authors.forename: J J
authors.initials: JJ
authors.lastname: Gilmartin
authors.forename: R M
authors.initials: RM
authors.lastname: Rutherford
authors.forename: Anthony
authors.initials: A
authors.lastname: O'Regan
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000328:Adult; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D016009:Chi-Square Distribution; D018450:Disease Progression; D005260:Female; D006801:Humans; D007494:Ireland; D016015:Logistic Models; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D011653:Pulmonary Diffusing Capacity; D012189:Retrospective Studies; D017565:Sarcoidosis, Pulmonary / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D062606:Tertiary Care Centers; D013997:Time Factors; D015854:Up-Regulation; D014797:Vital Capacity
chemical_list: D000305:Adrenal Cortex Hormones; D015415:Biomarkers; D002097:C-Reactive Protein
keywords: Sarcoidosis, C-reactive protein (CRP), predictive value, progression