Abstract:ObjectiveTo explore the correlation between blood lipid levels and IBD disease activity and the predictive significance of apolipoprotein (APO) B/A-1 ratio in active IBD. Methods A total of 271 IBD patients and 271 healthy controls who were hospitalized in Nanjing Drum Tower Hospital from January 2019 to December 2020 were seleeted. The differences in APOA-1, APOB, TG, TC, HDL-C, and LDL-C levels between the two groups were analyzed. The clinical and endoscopic activity indices, as well as C-reactive protein (CRP) and fecal calprotectin (FC) levels were also evaluated in patients with IBD, and the APOB/A-1 ratio was compared between remission and active IBD. Results A total of 271 IBD patients were included, including 224 patients with Crohn's disease (CD) and 47 patients with ulcerative colitis (UC). Compared with the control group, the levels of APOA-1, APOB, TC, HDL-C and LDL-C in the CD grouPand UC grouPwere decreased (P<0.05). Compared with CD in remission, the APOB/A-1 ratio in active phase was higher, and it was the highest in severe active CD (P<0.05). With APOB/A-1>0.68, the risk of severe active CD increased (P<0.05). Conclusion IBD patients and healthy people have different blood lipid levels, and APOB/A-1 has predictive value for severe active CD.