The association between circulating high-sensitivity C-reactive protein concentration and pathologic measures of colonic inflammation
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.
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.
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.
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.
KeywordsC-reactive protein Inflammation Colorectal cancer Obesity
This study was supported by Seraph Foundation; Frederik B. Bang Award for Student Research in Pathobiology, Johns Hopkins Bloomberg School of Public Health; Maryland Cigarette Restitution Fund at Johns Hopkins; and the National Cancer Institute (T32 CA009314). The content of this manuscript is solely the responsibility of the authors and does not necessarily represent the official views of the National Cancer Institute or the National Institutes of Health.
Conflict of interest
The authors have no conflict of interest to disclose.
- 12.World Cancer Research Fund/American Institute for Cancer Research (2011) Continuous update project. Food, nutrition, physical activity, and the prevention of colorectal cancer. AICR, Washington, DCGoogle Scholar
- 20.Sabatine MS, Morrow DA, Jablonski KA et al (2007) Prognostic significance of the Centers for Disease Control/American Heart Association high-sensitivity C-reactive protein cut points for cardiovascular and other outcomes in patients with stable coronary artery disease. Circulation 115:1528–1536PubMedCrossRefGoogle Scholar
- 24.World Cancer Research Fund/American Institute for Cancer Research (2007) Food, nutrition, physical activity, and the prevention of cancer: a global perspective. AICR, Washington, DCGoogle Scholar