title: The association between circulating high-sensitivity C-reactive protein concentration and pathologic measures of colonic inflammation.
abstract: OBJECTIVE
  C-reactive protein (CRP), an inflammation marker, is associated with colorectal cancer (CRC) risk in some prospective studies. Whether increased CRP is indicative of colonic inflammation, a possible CRC cause, or of other sources of inflammation (e.g., adiposity), is unknown. Thus, we evaluated the association between CRP and colonic mucosal measures of inflammation.
  
  
  METHODS
  151 adults undergoing colonoscopy provided a blood sample and random left- and right-side colonic mucosal biopsies. Height and weight were measured, and lifestyle information was collected. High-sensitivity C-reactive protein (hsCRP) was measured by immunoturbidometric assay. A gastrointestinal pathologist evaluated biopsies for seven colonic inflammation measures. Of 119 participants with complete information, 24 had an inflammatory bowel disease (IBD) history and were analyzed separately. We calculated the number of colonic inflammation measures present in both biopsies, and separately for right and left biopsies. Adjusted geometric mean hsCRP was calculated using linear regression, overall, by demographic and lifestyle factors, and inflammation measures.
  
  
  RESULTS
  Most participants had ≥ 1 colonic inflammation measure (0: 21 %, 1: 39 %, ≥ 2: 40 %). Adjusted mean hsCRP did not increase with increasing number of inflammation measures (0: 1.67; 1: 1.33; ≥ 2: 1.01 mg/L; p trend = 0.21). Obese (2.03 mg/L) and overweight (1.61 mg/L) participants had higher adjusted mean hsCRP than normal-weight participants (0.62 mg/L; p trend <0.0001). Patterns were similar for participants with a history of IBD.
  
  
  CONCLUSIONS
  hsCRP concentration was not associated with colonic inflammation, although hsCRP increased with adiposity. The hsCRP-CRC association may be explained by residual confounding by other risk factors, such as adiposity, rather than by CRP marking colonic inflammation.
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA, cjoshu@jhsph.edu.
authors.forename: Corinne E
authors.initials: CE
authors.lastname: Joshu
authors.forename: Kostantinos K
authors.initials: KK
authors.lastname: Tsilidis
authors.forename: Sarah B
authors.initials: SB
authors.lastname: Peskoe
authors.forename: Francis M
authors.initials: FM
authors.lastname: Giardiello
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Dluzniewski
authors.forename: William G
authors.initials: WG
authors.lastname: Nelson
authors.forename: Christine A
authors.initials: CA
authors.lastname: Iacobuzio-Donahue
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Platz
mesh_terms: D015415:Biomarkers / Q000097:blood; D014408:Biomarkers, Tumor / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D016022:Case-Control Studies; D003106:Colon / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000097:blood* / Q000473:pathology*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000473:pathology; D043183:Irritable Bowel Syndrome / Q000097:blood* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000473:pathology; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D014408:Biomarkers, Tumor; D002097:C-Reactive Protein