Research aims: Aims of this research study were to compare the serum concentrations of GDF 15 between inflammatory bowel disease patients and healthy controls, as well as to investigate the connection between the serum concentrations of GDF-15 and other clinical, antropometric and laboratory parameters in IBD patients. Inflammatory bowel disease is a group of chronic immune mediated diseases characterized by periods of relapse and remission. In addition to symptoms and complications involving the digestive tract, this population of patients is burdened by various extraintestinal manifestations which substantially contribute to greater morbidity and mortality. As serum concentrations of growth-differentiation factor-15 (GDF-15) were shown to be an independent predictor of poor outcomes in many diseases, we aimed to explore an association between GDF-15 and IBD. Study participants and procedures: The study included 90 adult patients diagnosed with IBD, 42 of which were ulcerative colitis patients and 48 Crohn disease patients, as well as 63 healthy age and sex-matched controls. Physical examination was performed on all study participants, after which height and weight measurements were taken, and body mass index calculated. Next, hip and waist circumference along with blood pressure were performed, as well as blood sampling for laboratory tests. Disease activity assessment was performed by two independent gastroenterology specialists with a special interest in inflammatory bowel disease treatment, using current and validated scoring systems. Serum GDF-15 concentrations were analyzed using the electrochemiluminescence immunoassay on the Cobas e800 analyzer (Elecsys, Roche Diagnostics). Results: In IBD patients, serum GDF-15 concentrations were significantly higher in comparison to the healthy controls [GDF-15 concentration averaged 800 pg/ml (512-1154 pg/ml) in the IBD group compared to 412 pg/ml (407-424 pg/ml) in the control group, P < 0.001)]. No difference in GDF-15 serum concentrations was found between patients with Crohn’s disease and ulcerative colitis [(average GDF-15 concentrations of 807 pg/ml (554-1451 pg/ml) in the Crohn's disease group and 790 pg/ml (509-956 pg/ml) in the ulcerative colitis group, P = 0.324)]. Moreover, multiple linear regression analysis showed that GDF-15 levels predict CD and UC severity independent of age, sex and C-reactive protein levels. Conclusion: Results showed significantly higher average serum concentrations of GDF-15 in the IBD group compared to the control group. Finally, an association between GDF-15 and indices of anemia was established. Overall, the results of the present study suggest a potential role of this biomarker in IBD pathophysiology. Yet, it remains elusive whether GDF-15 might be used as a prognostic indicator in these patients.