Metabolic Syndrome in Inflammatory Bowel Disease: Association with Genetic Markers of Obesity and Inflammation

Abstract

Background: This study analyzed poorly understood relationship of two overlapping conditions: metabolic syndrome (MeS) and inflammatory bowel disease (IBD), both associated with inflammation in the visceral adipose tissue. Methods: Newly diagnosed 104 IBD patients, of which 50 Crohn's disease (CD) and 54 ulcerative colitis (UC), and 45 non-IBD controls were examined for MeS-related obesity and lipid markers. Th-17 immune genes IL17A, IL17F, IL23A, and TLR9 mRNAs were measured in intestinal mucosa by qRT-PCR. Subjects were genotyped for obesity-associated FTO variant rs9939609 by polymerase chain reaction-amplification refractory mutation system. Results: CD was associated with MeS (P = 0.01), while both CD and UC were associated with central obesity (P = 10(-5), P = 0.002, respectively) and low levels of high-density lipoprotein (HDL) cholesterol (P = 5 x 10(-6), P = 6 x 10(-6), respectively). IBD lipid profile was characterized by decreased total and HDL cholesterol, while low-density lipoprotein cholesterol was reduced only in CD. Negative correlations were found between total cholesterol and CD activity index (P = 0.005), waist circumference and IL17A as well as IL17F mRNA levels in inflamed CD colon (P = 0.003, P = 0.001, respectively). Carriers of FTO rs9939609 AA genotype showed increased risk of CD (OR 2.6, P = 0.01). Conclusions: MeS, central obesity, and dyslipidemia could be important for IBD pathogenesis. This could influence therapeutic approaches and prevention strategies in high-risk groups.