[Association between serum indirect bilirubin levels and arterial stiffness in middle-aged and elderly women with type 2 diabetes].

This study aims to research the relationship between arterial stiffness and serum indirect bilirub in levels(IBIL)in patients with type 2 diabetes by measuring brachial-ankle pulse wave velocity (baPWV). The clinical data of 1 327 patients with T2DM admitted to Qingdao Huangdao District People's Hospital from July 1st, 2018 to March 1st, 2024 were retrospectively and cross-sectionally analyzed (609 men and 718 women; age range, 45.3-79.5 years; median age, 60.3 years; mean age, 61.4 years). The subjects were stratified based on gender-specific quartiles of IBIL values(male, Q1:<6.7 μmol/L, Q2:6.7-8.9 μmol/L, Q3:8.9-12.3 μmol/L, Q4:≥12.3 μmol/L;female, Q1:<6.4 μmol/L, Q2:6.4-7.9 μmol/L, Q3:7.9-10.4 μmol/L, Q4:≥10.4 μmol/L), and a high baPWV was defined as greater than 18.37 m/s (75th percentile). The results showed that the serum IBIL concentration was negatively correlated with the duration of diabetes (r=-0.142, P=0.010), the SBP (r=-0.158, P=0.005) and the baPWV (r=-0.194, P<0.001) in women and was positively correlated with TC (men: r=0.282, P<0.001; women: r=0.237, P<0.001), HDL-C (men: r=0.171, P=0.011; women: r=0.287, P<0.001) and LDL-C (men: r=0.196, P=0.009; women: r=0.233, P<0.001) levels in both genders. Dividing IBIL levels into quartiles, there were significant statistical differences in the incidence of high baPWV among different subgroups of female patients (χ²=36.468,P<0.001), and the incidence of high baPWV showed a decreasing trend with increasing IBIL levels. After adjusting for confounding factors, the IB levels were inversely associated with a greater risk of a high baPWV both as a continuous variable [a 1-SD difference; odds ratio (OR):0.836; 95% confidence interval (CI):0.774-0.942; P=0.009] and when categorized in quartiles (the highest vs. the lowest quartile; OR:0.381; 95%CI:0.162-0.897; P=0.025) in women but not in men. Low IBIL levels were significantly associated with arterial stiffness in middle-aged and elderly women with type 2 diabetes. In conclusion, the serum IBIL levels were independent protective factors for macrovascular disease in middle-aged and elderly diabetic women.