Data from: Lp-PLA2 and dual antiplatelet agents in intracranial arterial stenosis

Objective: To evaluate the interaction effect of lipoprotein-associated
phospholipase A2 (Lp-PLA2) activity on the efficacy and safety of
dual/single antiplatelet therapy in patients with and without intracranial
arterial stenosis (ICAS) by the Clopidogrel in High-Risk Patients with
Acute Non-disabling Cerebrovascular Events (CHANCE) trial. Methods:
Subjects with both MR imaging analysis and Lp-PLA2 testing results were
included in the current subanalysis. The interaction of Lp-PLA2 activity
with the effects of dual and single antiplatelet therapy were analyzed
through cox proportional hazards regressions model. Results: Among the 797
patients, the mean age was 63.1±10.8 years, 518 (65%) were men, 356
(44.7%) patients had ICAS and 441 (55.3%) did not. There are significantly
more patients with elevated Lp-PLA2 activity in the ICAS group than that
in the non-ICAS group (43.8% versus 35.4%, p=0.02). There was significant
interaction between Lp-PLA2 activity levels and the two antiplatelet
therapy for prevention of stroke recurrences and combined vascular events
even after adjustment for confounding factors exclusively for patients
with ICAS (p=0.016, 0.016, respectively), but not for those without
(p=0.289, 0.597, respectively). Compared with aspirin alone, dual
antiplatelet therapy significantly reduced the risk of stroke recurrences
and combined vascular events (adjusted hazard ratio=0.33 [0.12-0.88],
p=0.026; 0.33 [0.12-0.88], p=0.026, respectively) for patients with both
ICAS and non-elevated Lp-PLA2 activity. Conclusions: Presence of both ICAS
and non-elevated Lp-PLA2 activity may predict better response to dual
antiplatelet therapy in prevention of recurrent strokes and combined
vascular events for patients with minor stroke or high-risk TIA.