High Apolipoprotein B Levels are Associated with an Increased Risk of Recurrent Acute Ischemic Stroke: A Nested Case-Control Study.

Mendelian randomization studies have identified that apolipoprotein B (ApoB) is the primary genetic determinant of ischemic stroke, rather than other lipid markers. However, its association with recurrent non-cardioembolic acute ischemic stroke (NCAIS) remains unclear. This study aimed to investigate this association. This study recruited 578 patients with acute ischemic stroke, excluding those with cardiogenic embolism. After a 3-year follow-up, a total of 428 patients completed the prospective cohort study. A Cox regression model was used to evaluate the association between ApoB levels at admission and the recurrence rate. Additionally, a nested case-control study was conducted by comparing blood samples collected at the time of recurrence from recurrent patients with those from non-recurrent patients. Binary logistic regression and ROC analysis were used to assess the association between serum ApoB, low-density lipoprotein cholesterol (LDL-C), and recurrent stroke at the time of recurrence. The Cox regression model demonstrated that ApoB levels at admission were independently associated with an increased risk of recurrent NCAIS (HR=6.697; 95%CI 2.581-17.374, P < 0.001). Recurrent stroke patients had significantly higher serum ApoB levels at admission than non-recurrent ones [0.85 g/L (IQR 0.21) vs. 0.63 g/L (IQR 0.15)]. In ROC analysis, ApoB (AUC = 0.732) showed a greater discriminatory ability for recurrent stroke than LDL-C (AUC = 0.685). Higher serum ApoB levels increased the risk of recurrence in patients with NCAIS, and ApoB demonstrated better discriminatory ability than LDL-C after therapy. These findings suggest that routine ApoB measurement may help improve secondary stroke risk assessment.