To investigate serum levels of small dense low-density lipoprotein cholesterol (sdLDL-C) in transient ischemic attacks (TIA) patients and assess their predictive values for subsequent stroke risk after TIA.

Clinical case-control study. Serum sdLDL-C levels were determined in 96 TIA patients who were admitted to Jinling Hospital from January 2016 to December 2016 and 44 healthy controls who had contemporaneously visited Jinling Hospital For a routine or the routine. ABCD3-I scores in TIA patients were calculated. All TIA patients were classified into three subgroups: high-risk (8≤ABCD3-I≤ 13, n=23), moderate-risk (4≤ABCD3-I≤ 7, n=36) and low-risk (0≤ABCD3-I≤ 3, n=37). Total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and other lipid/lipoprotein parameters in TIA patients and controls were also analyzed. Spearman correlation analyses and multivariate linear regression analyses were performed to investigate the association of serum sdLDL-C levels with ABCD3-I scores. Logistic regression analyses were performed to investigate the predictive values of serum sdLDL-C for TIA patients.

Serum sdLDL-C levels were significantly increased in TIA patients compared with controls (t=-5.202, P<0.001). Furthermore, sdLDL-C levels in high-risk patients were significantly higher than that in moderate-risk (t=3.534, P=0.001) and low-risk (t=4.154, P<0.001) patients. Serum sdLDL-C levels were positively correlated with ABCD3-I scores (r=0.317, P=0.002) in TIA patients. The stepwise multiple regression analysis showed that only sdLDL-C was a significant independent predictor of ABCD3-I scores (β=0.481, P=0.032, adjusted R²=0.189), after adjusting for age, gender, blood pressure and other lipid/lipoprotein parameters. Binary Logistic analyses indicated that serum sdLDL-C levels were closely associated with TIA presence (OR=2.84, 95% CI=1.42-5.70, P=0.003), after adjustment with age, gender, blood pressure and other lipid/lipoprotein parameters.

Serum sdLDL-C levels were increased in TIA patients. The significantly independent associations of sdLDL-C levels with ABCD3-I scores were observed. Serum sdLDL-C levels may contribute to assessing subsequent stroke risk after TIA.(Chin J Lab Med, 2018, 41: 316-320)

Ischemic attack, transient; Cholesterol, LDL; Stroke; Risk factors; Biomarkers