Association between high-sensitivity C-reactive protein and ischemic stroke outcomes under different glucose metabolism statuses: a retrospective cohort study

High-sensitivity C-reactive protein (hs-CRP), a marker of systemic inflammation, is associated with clinical outcomes after stroke. This study aimed to explore the relationship between baseline hs-CRP levels and outcomes in patients with acute ischemic stroke (AIS) with different glucose metabolism statuses. Using data from the China National Stroke Registry III, patients with AIS or transient ischemic attack were categorized by baseline hs-CRP (low-risk, <1.0 mg/L; average-risk, 1–3 mg/L; and high-risk, >3 mg/L) and glycated hemoglobin A1c (HbA1c)-defined glucose status: normal glucose regulation (NGR), pre-diabetes (pre-DM), and diabetes (DM). The primary outcome was poor functional outcomes (modified Rankin Scale scores of 2–6) at 3 months, with secondary outcomes including poor functional outcomes at 1 year and stroke recurrence at both time points. Multivariable logistic proportional hazards models and restricted cubic spline analysis were used to explore the association between hs-CRP and functional outcomes across glucose metabolism statuses. This study enrolled 6,916 patients (mean age, 62.4 ± 11.2 years; 67.4% male). Compared with the low-risk group, the high-risk hs-CRP group had a higher risk of poor functional outcomes at 3 months among patients with DM (adjusted odds ratio [aOR] = 1.38, 95% confidence interval [CI] = 1.07–1.77, p = 0.0117) and NGR (aOR = 1.58, 95% CI = 1.19–2.09, p = 0.0015), but not pre-DM (aOR = 1.16, 95% CI = 0.86–1.58, p = 0.3263). A near-linear dose-response relationship was observed in the total population and pre-DM group. No significant associations were found at 1 year or for stroke recurrence. Glucose metabolism status influenced the association between hs-CRP levels and poor functional outcomes at 3 months after stroke.