Abstract: Objective To investigate the relationship between serum fibroblast growth factor 21 （FGF21） level and lower extremity atherosclerosis in type 2 diabetic patients. Methods Patients with type 2 diabetes diagnosed clinically in Dazu District People's Hospital of Chongqing from November 2017 to September 2018 were enrolled in the study. Anthropometric and blood biochemical parameters of the patients were tested and the intima-media thickness （IMT） of the lower extremity was measured. Differences between atherosclerotic type 2 diabetic patients and non-atherosclerotic diabetic patients were compared. Multivariable linear regression was used to analyze the correlation between IMT and serum FGF21. Results A total of 121 patients with type 2 diabetes were enrolled, including 69 patients without atherosclerosis and 52 patients with atherosclerosis. The prevalence rate of atherosclerosis was 43.0%. There were 42 and 31 males,and 27 and 21 females in the two groups, respectively （P>0.05）. The course of disease and waist-to-hip ratio in the atherosclerosis group were higher than those in the atherosclerosis-free group （P<0.01）. There were no significant differences in mean age, BMI, systolic blood pressure and diastolic blood pressure （P>0.05 for all）. Fasting blood glucose（FBG）, triglyceride, glycosylated hemoglobin（HbA1c）, insulin resistance index（HOMA-IR）, IMT and FGF21 in patients with atherosclerosis were higher than those in non-atherosclerotic patients （P<0.01 for all）. Correlation analysis showed that IMT was positively correlated with waist-to-hip ratio, FBG, HbA1c, HOMA-IR and FGF21 （r=0.271, 0.319, 0.322, 0.372, 0.265; P<0.05）. Multivariable linear regression model showed that waist-to-hip ratio, FBGand FGF21 were independent factors affecting IMT（Standard partial regression coefficient：0.194,0.341, 0.657,respectively）. Conclusion IMT in patients with type 2 diabetes was associated with waist-to-hip ratio, FBG and FGF21. Serum FGF21 levels may play a role in the formation of lower extremity atherosclerosis in patients with type 2 diabetes mellitus.

Key words: Type 2 diabetes, Fibroblast growth factor 21, Atherosclerosis, Lower extremity