Abstract: Abstract： Objective To investigate the relationship between waist circumference and new-onset non-alcoholic fatty liver disease in non- obese patients with diabetes mellitus. Methods A total of 1 950 patients with diabetes mellitus, whodetermined fasting plasma glucose（FPG） ≥7.0 mmol/L or who were using hypoglycemic drugs and FPG < 7.0 mmol/L， and body mass index (BMI) < 25 kg/m2, was selected in this study using prospective cohort method. Patients were divided into five groups according to the baseline data of waist circumference, including waist circumference<78 cm (A group, n=387), 78 cm90 cm (E group, n=421). Multiple Logistic regression model was used to analyze influential factors of new-onset non-alcoholic fatty liver disease in non- obese patients with diabetes mellitus. Re⁃ sults The average duration of follow-up was（47.24±5.13) months. The incidence rate was 11.85% (231/1 950) in patients with non-alcoholic fatty liver disease. The incidence rates were 6.98%, 9.28%, 12.38%, 14.19% and 15.68% in A, B, C, D and E groups, and which were increased with the increased waist circumference (P＜ 0.05). Results of multiple Logistic re⁃ gression model analysis showed that compared with A group， OR values were 1.97 and 2.19 in D and E groups respectively （P＜ 0.05). Conclusion Waist circumference≥85 cm was the risk factors of new-onset non-alcoholic fatty liver disease in non-obese patients with diabetes mellitus.

Key words: diabetes mellitus, cohort studies, Logistic models, non-alcoholic fatty liver disease, waist circumference