Proteomics and the Risk of Incident Embolic and Thrombotic Stroke.

Objective: Personalized approaches to ischemic stroke diagnosis are needed. We determine differences in proteomic signatures of incident embolic (EIS) and thrombotic stroke (TIS) by age and resultant pathways using large-scale proteomics.

Methods: Participants in the Atherosclerosis Risk in Communities Study (ARIC) from visit 2 (V2, 1990-1992) until 2020 without prevalent stroke with available SomaScan data (4,955 protein targets) at V2 (mid-life, n = 10,929), and then again at visit 5 (V5, 2011-2013, n = 4,463) were included. Covariate adjusted Cox hazard models determined the association between proteins, and adjudicated incident EIS or TIS from V2 to V5 and from V5 to 2020.

Results: Among 10,929 participants (56% female, 23% Black, follow-up ~20 years), 20 proteins measured in mid-life were associated with either EIS (n = 168) or TIS (n = 459) in mid-life, and 4 measured in late-life were associated with late-life stroke (73 EIS and 124 TIS events) at the Bonferroni threshold p < 1E-5. In mid-life, N-terminal pro-B-type natriuretic peptide (NPPB) was significantly associated with EIS, but not TIS (p-difference = 9.14E-7). Nineteen mid-life proteins were strongly associated with TIS; 7 strongly associated with TIS and only nominally (p < 0.05) with EIS and the remaining 12 with TIS only. In late-life, NPPB, serine protease inhibitor Kazal-type 4, oligodendrocyte-myelin-glycoprotein, and neurocan-core protein were significantly associated with EIS, but not TIS. Ingenuity Pathway Analysis tools implicated cancer for EIS-associated proteins, whereas TIS pathways reflected cell-structure and atherogenesis.

Interpretation: We identified plasma proteins associated with risk of EIS versus TIS reflecting distinct stroke mechanisms: cardiac dysfunction protein in EIS (eg, NPPB) and inflammation dysregulation in TIS (eg, interleukins). ANN NEUROL 2025.