High Interleukin-6 Levels Are Associated With Large-Artery Atherosclerotic Stroke

Interleukins (ILs) play several critical roles in modulating the occurrence and development of atherosclerosis-related diseases. We aimed to investigate the associations between ILs and the diagnosis, progress, and functional outcome in patients with large-artery atherosclerotic (LAA) stroke.

Plasma levels of IL-2, IL-4, IL-6, and IL-10 were measured within 24 hours after stroke in 181 patients with first-time LAA stroke and on admission in 181 age-matched and sex-matched controls. NIHSS scores were recorded at admission and on Day 1, Day 2, Day 3, Day 4, and Day 5 after the stroke. Functional outcome was measured by the modified Rankin Scale at 3 months after stroke. Subgroup analyses were compared based on short-term progress within 5 days (ΔNIHSS ≥3) and 3-month unfavorable outcome (modified Rankin Scale >2). Logistic regression analysis adjusted for relevant confounders was performed.

IL-6 levels were higher in patients with LAA stroke than in controls [AOR (95% CI), 0.701 (95% CI 0.651-0.748, P <0.001], with an area under the receiver operating characteristic curve (AUC) of 0.701. Higher IL-6 levels were associated with short-term progression [AOR (95% CI), 1.070 (1.009, 1.135), P =0.025], with an AUC value of 0.720. Higher IL-6 levels were associated with unfavorable outcomes [AOR (95% CI), 1.075 (1.002, 1.153), P =0.040], with an AUC value of 0.658. No difference in IL-2, IL-4, or IL-10 was found between the groups.

Plasma levels of IL-6 are higher in patients with LAA stroke and are independently associated with short-term progression and 3-month functional outcomes after stroke.