Abstract Body (Do not enter title and authors here): Background
Patients with myocardial infarction (MI) are at increased risk of ischemic stroke (IS). We previously showed that the biomarker C-reactive protein (CRP) is associated with an increased long-term risk of both death and heart failure in patients with MI. The long-term prognostic value of CRP to determine the risk of IS in such individuals is unknown.

Aim
To assess the association between CRP and long-term risk of IS in patients with MI and no previous history of IS or transient ischemic attack (TIA).

Methods
We used Danish nationwide registries to identify patients without prior IS or TIA who presented with a diagnosis of MI from 2013 through 2020 and who had a CRP measurement ≦24 hours of index hospitalization. The primary endpoint was IS. Cumulative incidence curves were constructed for the outcome at 0-30 and 31-365 days. We used multivariable Cox regression with average treatment effect modeling to render standardized absolute and relative risks of IS at 0-30 and 31-365 days according to CRP quartiles. Models were adjusted for demographics and clinical features, including high-sensitivity troponin concentrations.

Results
After exclusion of 2,313 patients with a history of IS or TIA, the final cohort comprised 26,722 individuals. Median CRP was 4 mg/l, and quartile intervals were: quartile 1: <2.9 mg/l, quartile 2: 2.9 to <4 mg/l, quartile 3: 4 to <12 mg/l, and quartile 4: ≥12 mg/l. Patients in quartile 4 were older and had a higher prevalence of comorbidities, including hypertension, diabetes, and atrial fibrillation. At 0-30 days, 109 patients were diagnosed with IS and an additional 182 were diagnosed with IS at 31-365 days. The standardized absolute risk of IS was lowest in CRP quartile 1 at both 0-30 days (4.0 % (Figure 1) and 31-365 days (5.6 %) (Figure 2). For example, the relative risks of IS for quartile 4 vs. quartile 1 were 1.89 (95 % CI 0.94-2.84) at 0-30 days and 1.46 (95 % CI 0.80-2.11) at 31-365 days.

Conclusion
In patients with MI and without prior IS or TIA, higher CRP concentrations appeared to be associated with a higher risk of IS at both one month and one year.