S814 The C-Reactive Protein to Albumin Ratio vs C-Reactive Protein in Correlation With Active Inflammation in Patients With Inflammatory Bowel Disease

Abstract

Introduction: C-reactive protein (CRP) and albumin are two hepatic proteins that have been used to assess inflammation and nutritional status, respectively. The CRP to albumin ratio has been used for prognostication in patients with solid tumors and provides a more consistent marker for mortality in septic patients. The aim of this study was to compare the CRP/albumin ratio versus CRP alone in correlation with active inflammation in IBD. Additionally, we stratified this analysis by inflammation severity. Methods: Retrospective analysis of adults with an ICD-9/10 code diagnosis of IBD during hospitalization for IBD flare symptoms at a tertiary care center between January 1st 2013 to June 1st 2017. Active inflammation was defined by chronic active histologic changes seen on targeted ileal or colonic biopsies or by inflammation seen in terminal ileum or colon on XCI or colonoscopy. Data including the patients’ XCI and colonoscopy reports were extracted from the institution’s integrated electronic data repository and electronic chart review. This study was approved by the institutional review board. To determine the relationship of the CRP/albumin ratio versus CRP alone with active inflammation, Spearman’s correlation analysis was used. The Z-statistic was used to compare the areas under the receiver operating curve (AUC). Results: A total of 760 unique patients were analyzed of which 519 (348 CD, 160 UC, 11 mixed) met inclusion criteria. Two hundred and twenty five were found to have active inflammation with 42.2% having albumin and 35.4% having CRP on hospital admission. The cohort consisted of the characteristics outlined in Table 1. CRP/Albumin ratio had significant correlation to active inflammation (r=0.14, p< 0.0329). ROC analysis (Figure 1a) showed increasing AUC with no inflammation, mild, moderate and severe disease activity (0.482, 0.580, 0.615 and 0.659, respectively). CRP also had significant correlation with disease activity (r=0.14, p< 0.0285). ROC analysis (Figure 1b) showed increasing AUC with no inflammation, mild, moderate and severe disease activity (0.494, 0.590, 0.611 and 0.655, respectively). Conclusion: CRP and albumin are inexpensive biomarkers that can be used as a prognostication tools for active inflammation. Both CRP/Albumin ratio and CRP level alone correlate with active inflammation. The CRP/Albumin ratio suggests a stronger correlation with moderate and severe disease activity in IBD while CRP level alone has a stronger correlation with mild disease activity.Table 1.: a. Outcome: Medication Adherence. Medication Adherence, Patient Activation and Associated Patient CharacteristicsFigure 1.: Flowdiagram of exclusion and inclusion of cases.