The predictive value of small densed low-density lipoprotein cholesterol and HbA1C for cardiovascular and cerebrovascular events in elderly patients with type 2 diabetes mellitus

Objective To investigate the serum level of low density lipoprotein cholesterol (sdLDL-C) in elderly patients (age≥65 years) with type 2 diabetes mellitus (T2DM) and the its predictive value in evaluatingthe risk of cardiovascular and cerebrovascularevents in elderly patients with T2DM. Methods In this retrospective study,386 elderly patients with T2DM were collected from December 2014 to December 2016, the averageage was (72.7±5.4) years old, including 269 males and 117 females; 92 of whom had cardiovascular events during follow-up, the averageage was (72.9 ± 5.2) years old, including 65 males and 27 females, and serum sdLDL-C level was detected. Meanwhile, biomarkers such as lipoprotein (a), apolipoprotein B, apolipoprotein AI and hypersensitive c-reactive protein were analyzedin all the patients.Univariate and multivariate factors were used to analyze the relationship between each variable and the occurrence of cardiovascular and cerebrovascular events. The correlation between LDL-C, sdLDL-C of all subjects with age and other lipid indexes were analyzed. ROC curve was used to determine the predictive value of sdLDL-C elevation for cardiovascular and cerebrovascular events in elderly patients with T2DM. Results The levels of LDL-c, sdLDL-C, non-HDL-C, GLU, HbA1c and ApoB were significantly higher in theCardio-cerebral vascular event group (t=3.26, 3.46, 2.91, 2.47, 4.03, 3.00, P<0.05). While the levels of apolipoprotein AI was significantly lower than those in theNon-cardio-cerebral vascular event group (t=-2.39, P<0.05). Cox regression analysis showed that sdLDL-C per 10 mg/dl was independently correlated with the risk of cardiovascular and cerebrovascular events(HR 1.281, 95%CI 1.225-16.032, P<0.01)after adjusted for age. SdLDL-C was positively correlated with TG, non-HDL-C and ApoB (r=0.323, 0.588, 0.623, P<0.01) and was negativelycorrelated correlation with age, HDL-C and apolipoprotein AI (r=-0.363, -0.301, P<0.01), ROC curve analysis showed that sdLDL-C had a strong ability to predict the occurrence of cardiovascular and cerebrovascular events (AUC=0.736, 95%CI 0.554 9-0.918 2, P=0.003), while HbA1c also had a strong ability to predict the occurrence of cardiovascular and cerebrovascular events(AUC=0.725, 95%CI 0.524 3-0.927 3, P=0.006). Combined sdLDL-C with HbA1had the strong ability to predict the occurrence of cardiovascular and cerebrovascular events (AUC=0.837, 95%CI 0.711 4-0.973 5, P=0.001). Conclusions The elevation of serum sdLDL-C in elderly patients with T2DM wasa significantly independentrisk factorof cardiovascular and cerebrovascular events. Serum sdLDL-C had a higher clinical value than LDL-C, which was expected to be the most effective predictor of lipid profile in riak assessment of cardiovascular and cerebrovascular events in elderly patients with T2DM. Key words: Diabetes mellitus, type 2; Cardiovascular diseases; Cholesterol, LDL; Biomarkers; Risk factors; Forecasting