[A correlation study between serum direct bilirubin and lipid in type 2 diabetic patients].

Objective: To investigate the association between DBil with normal range and serum lipid in type 2 diabetic patients.
Methods: A total of 979 subjects with type 2 diabetes admitted to the Department of Endocrinology of Chinese PLA General Hospital from June 2012 to June 2013 were included for the study. Serum DBil, TC, TG, HDL-C and LDL-C levels were collected for the analyses. Subjects were divided into four groups based on the DBil levels: Q1 group (<2.2 µmol/L), Q2 group (2.2-< 2.9 µmol/L), Q3 group (2.9-< 3.9 µmol/L) and Q4 group ( ≥ 3.9 µmol/L) .
Results: (1) TC, TG, LDL-C levels were significantly lower in Q4 group than those in the other three Q groups after adjustment of age, gender, duration of diabetes, BMI, smoking, drinking, glycosylated hemoglobin A1c (HbA1c) , fasting plasma glucose (FPG), medication, ALT, AST and fatty liver. No difference could be viewed in HDL-C level between each group (P = 0.65). (2) Pearson correlation analyses showed that DBil was inversely correlated with TC (r = -0.33, P < 0.01), TG (r = -0.23, P < 0.01), LDL-C (r = -0.18, P < 0.01), and positively correlated with HDL-C level in men (r = 0.14, P < 0.01), respectively. Multiple linear regression analyses showed DBil was an independent impact factor for TC, TG and LDL-C. (3) Compared with Q1 group, the odds ratio (OR) for dyslipidemia was 0.54 (95%CI 0.35-0.82, P < 0.01), 0.56 (95%CI 0.37-0.85, P < 0.01) and 0.44 (95%CI 0.29-0.69, P < 0.01) in Q2, Q3 and Q4 group, respectively, after age, gender, duration of diabetes, BMI, smoking, drinking, HbA1c, FPG, medication, ALT, AST and fatty liver were adjusted. Moreover, the OR for dyslipidemia was much lower in Q4 man subjects with age<55 years , HbA1c ≥ 6.5%, BMI<25 kg/m(2), and with no fatty liver.
Conclusion: DBil in normal range was closely associated with lipid profile in type 2 diabetes. It might play a protective effect in dyslipidemia.