Subclinical inflammation and alterations in plasma antioxidants in well nourished patients with quiescent inflammatory bowel disease (IBD)

Aim: The aim of this project was to assess the antioxidant and inflammatory status in IBD patients in remission and compare the results to those of healthy controls (CON).

Methods: Inflammatory status (C-reactive protein (CRP), orosomucoid and faecal calprotectin, a non-invasive marker of intestinal inflammation) was assessed in 47 IBD patients (38±11yrs.; body mass index (BMI): 22.4±2.1kg/m²) and 47 healthy controls (38±11yrs.; BMI: 22.4±2.0kg/m²) pair-matched for sex-, age- and BMI. All patients were well nourished according to subjective global assessment, BMI and serum albumin >40g/l and in clinical remission (30 Crohn disease (CD), CDAI=66±45; 17 ulcerative colitis (UC), CAI=3±1.5) for at least 3 month, none was steroid-dependent. Plasma levels of antioxidants (selenium, lutein/zeaxanthin, retinol, β-cryptoxanthin, lycopene, α-and β-carotene) were compared. Results are expressed as median and interquartile range. Mann-Whitney-U test was used for statistical analysis.

Results: We observed differences in the inflammatory status with respect to CRP, orosomucoid and calprotectin in CD patients compared to healthy controls. In addition, some plasma antioxidants were significantly lower (see table) in the CD group. UC patients only showed significant higher calprotectin levels and decreases in α-carotene compared to healthy controls, but no significant changes with respect to all other values (see table).

Conclusion: CD patients even when they are in disease remission show clear signs of systemic and intestinal microinflammation and decreased levels of antioxidants. That might be caused by higher oxidative stress or different food intake. These findings are far less pronounced in UC patients where signs of inflammation were restricted to the intestinal level.