title: Can serum surfactant protein D or CC-chemokine ligand 18 predict outcome of interstitial lung disease in patients with early systemic sclerosis?
abstract: OBJECTIVE
  To examine the predictive significance of 2 pneumoproteins, surfactant protein D (SP-D) and CC-chemokine ligand 18 (CCL18), for the course of systemic sclerosis (SSc)-related interstitial lung disease.
  
  
  METHODS
  The pneumoproteins were determined in the baseline plasma samples of 266 patients with early SSc enrolled in the GENISOS observational cohort. They also were measured in 83 followup patient samples. Pulmonary function tests were obtained annually. The primary outcome was decline in forced vital capacity (FVC percentage predicted) over time. The predictive significance for longterm change in FVC was investigated by a joint analysis of longitudinal measurements (sequentially obtained FVC percentage predicted) and survival data.
  
  
  RESULTS
  SP-D and CCL18 levels were both higher in patients with SSc than in matched controls (p < 0.001 and p = 0.015, respectively). Baseline SP-D levels correlated with lower concomitantly obtained FVC (r = -0.27, p < 0.001), but did not predict the short-term decline in FVC at 1 year followup visit or its longterm decline rate. CCL18 showed a significant correlation with steeper short-term decline in FVC (p = 0.049), but was not a predictor of its longterm decline rate. Similarly, a composite score of SP-D and CCL18 was a significant predictor of short-term decline in FVC but did not predict its longterm decline rate. Further, the longitudinal change in these 2 pneumoproteins did not correlate with the concomitant percentage change in FVC.
  
  
  CONCLUSIONS
  SP-D correlated with concomitantly obtained FVC, while CCL18 was a predictor of short-term decline in FVC. However, neither SP-D nor CCL18 was a longterm predictor of FVC course in patients with early SSc.
authors.affiliation: University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.
authors.forename: Mona
authors.initials: M
authors.lastname: Elhaj
authors.forename: Julio
authors.initials: J
authors.lastname: Charles
authors.forename: Claudia
authors.initials: C
authors.lastname: Pedroza
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Liu
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Zhou
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Estrada-Y-Martin
authors.forename: Emilio B
authors.initials: EB
authors.lastname: Gonzalez
authors.forename: Dorothy E
authors.initials: DE
authors.lastname: Lewis
authors.forename: Hilda T
authors.initials: HT
authors.lastname: Draeger
authors.forename: Sarah
authors.initials: S
authors.lastname: Kim
authors.forename: Frank C
authors.initials: FC
authors.lastname: Arnett
authors.forename: Maureen D
authors.initials: MD
authors.lastname: Mayes
authors.forename: Shervin
authors.initials: S
authors.lastname: Assassi
mesh_terms: D000328:Adult; D000368:Aged; D019742:Chemokines, CC / Q000097:blood*; D018450:Disease Progression; D005260:Female; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000097:blood* / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D037663:Pulmonary Surfactant-Associated Protein D / Q000097:blood*; D012129:Respiratory Function Tests; D012595:Scleroderma, Systemic / Q000097:blood* / Q000150:complications / Q000503:physiopathology; D014797:Vital Capacity / Q000502:physiology
chemical_list: C111792:CCL18 protein, human; D019742:Chemokines, CC; D037663:Pulmonary Surfactant-Associated Protein D
keywords: CC-CHEMOKINE LIGAND 18; INTERSTITIAL LUNG DISEASE; SURFACTANT D; SYSTEMIC SCLEROSIS