Abstract
The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), and the systemic immune-inflammatory index (SIRI, neutrophils × monocytes/lymphocytes) have been identified as potential inflammatory biomarkers. In this work we aimed to analyze whether the hematological composite scores differ between inflammatory bowel disease (IBD) patients and healthy controls, and if they are related to disease activity. A total of 197 IBD patients-130 Crohn's (CD) disease and 67 ulcerative colitis (UC)-and 208 age- and sex-matched healthy controls were enrolled. C-reactive protein and fecal calprotectin were assessed. Multivariable linear regression analysis was executed. After adjustment, NLR and PLR, but not SIRI and MLR, were significantly higher in IBD patients compared to controls. C-reactive protein and SIRI and NLR were correlated in IBD patients. However, fecal calprotectin was not related to any of these blood scores. Furthermore, disease activity parameters were not associated with any of the blood composite scores in both CD and UC patients. In conclusion, NLR and PLR, but not SIRI and MLR, are independently higher in IBD patients compared to controls. However, the four hematological scores are not related to disease activity in either CD or UC patients. Based on these results, blood-based inflammatory scores may not serve as subrogated biomarkers of disease activity in IBD.