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

Abstract

<b><i>Background:</i></b> 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. <b><i>Methods:</i></b> 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 <i>IL17A</i>, <i>IL17F</i>, <i>IL23A,</i> and <i>TLR9</i> mRNAs were measured in intestinal mucosa by qRT-PCR. Subjects were genotyped for obesity-associated <i>FTO</i> variant rs9939609 by polymerase chain reaction-amplification refractory mutation system. <b><i>Results:</i></b> CD was associated with MeS (<i>P</i> = 0.01), while both CD and UC were associated with central obesity (<i>P</i> = 10^-5, <i>P</i> = 0.002, respectively) and low levels of high-density lipoprotein (HDL) cholesterol (<i>P</i> = 5 × 10^-6, <i>P</i> = 6 × 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 (<i>P</i> = 0.005), waist circumference and <i>IL17A</i> as well as <i>IL17F</i> mRNA levels in inflamed CD colon (<i>P</i> = 0.003, <i>P</i> = 0.001, respectively). Carriers of <i>FTO</i> rs9939609 AA genotype showed increased risk of CD (OR 2.6, <i>P</i> = 0.01). <b><i>Conclusions:</i></b> MeS, central obesity, and dyslipidemia could be important for IBD pathogenesis. This could influence therapeutic approaches and prevention strategies in high-risk groups.