title: Racial differences in the association of pentraxin-3 with kidney dysfunction: the Multi-Ethnic Study of Atherosclerosis.
abstract: BACKGROUND
  Pentraxin-3 (PTX3), an inflammatory marker thought to be related to vascular inflammation, is elevated in advanced chronic kidney disease (CKD). Whether PTX3 is associated with mild to moderate kidney dysfunction is unknown.
  
  
  METHODS
  We tested associations of proteins in the pentraxin family [PTX3, C-reactive protein (CRP) and serum amyloid protein (SAP)] with estimated glomerular filtration rate by cystatin C (eGFRcys) and microalbuminuria among 2824 participants in the Multi-Ethnic Study of Atherosclerosis. Associations were tested using multivariable linear regression with adjustment for demographics (age, gender, annual income), comorbidities (diabetes, hypertension, smoking, body mass index, low-density lipoprotein, high-density lipoprotein, triglycerides, ACE inhibitor and statin use) and systemic inflammation [interleukin-6 (IL-6)].
  
  
  RESULTS
  Among the 2824 participants, mean age was 62 years and mean eGFRcys was 94 mL/min/1.73 m(2); 25% were white, 25% Chinese, 25% African-American and 25% Hispanic. Among all participants after full adjustment, higher PTX3 was associated with lower eGFRcys independently of IL-6 (β - 3.0 mL/min/1.73 m(2) per unit increase in lnPTX3, P < 0.001). In contrast, CRP and SAP were associated with eGFRcys in demographic adjusted models, but these associations were attenuated after adjustment for comorbidities and IL-6 (lnCRP β - 0.06, P = 0.9; lnSAP β - 0.35, P = 0.7). There was a significant interaction with race/ethnicity (P < 0.001) in the association of PTX3 and eGFRcys. After adjustment for demographics, comorbidities and IL-6, this association was significant in blacks (β - 5.7 mL/min/1.73 m(2) per unit increase in lnPTX3, P = 0.002) but not in Hispanics (β - 2.4, P = 0.1), Chinese (β - 0.91, P = 0.5) or whites (β - 0.26, P = 0.9). PTX3 and CRP, but not SAP, had correlations with microalbuminuria in unadjusted models (Spearman coefficients PTX3 0.05, P = 0.005; CRP 0.07, P < 0.001; SAP 0.013, P = 0.5), but these were attenuated after full adjustment.
  
  
  CONCLUSIONS
  Endovascular inflammation may be an important mechanism associated with early kidney dysfunction, particularly among blacks. This mechanism appears to be independent of IL-6-regulated pathways.
authors.affiliation: Department of Medicine, Division of Nephrology, University of California San Francisco, San Francisco, CA, USA. ruth.dubin@ucsf.edu
authors.forename: Ruth
authors.initials: R
authors.lastname: Dubin
authors.forename: Michael
authors.initials: M
authors.lastname: Shlipak
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Li
authors.forename: Joachim
authors.initials: J
authors.lastname: Ix
authors.forename: Ian H
authors.initials: IH
authors.lastname: de Boer
authors.forename: Nancy
authors.initials: N
authors.lastname: Jenny
authors.forename: Carmen A
authors.initials: CA
authors.lastname: Peralta
mesh_terms: D050197:Atherosclerosis / Q000150:complications* / Q000208:ethnology* / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism*; D002097:C-Reactive Protein / Q000378:metabolism*; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D051437:Renal Insufficiency / Q000175:diagnosis* / Q000209:etiology / Q000378:metabolism; D000683:Serum Amyloid P-Component / Q000378:metabolism*; D000099153:Pentraxins
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein; D000683:Serum Amyloid P-Component; D000099153:Pentraxins