Endarterectomy patients with elevated levels of circulating IL-16 have fewer cardiovascular events during follow-up.

BACKGROUND AND PURPOSE: Increased interleukin 16 (IL-16) levels in carotid plaques have been associated with reduced incidence of cardiovascular (CV) events during follow-up in patients who underwent carotid endarterectomy (CEA). In the present study we aimed to determine whether high circulating levels of IL-16 also are associated with a decreased risk of CV events after CEA.

METHODS: Patients, who had their carotid plaques surgically removed (n=473), were followed for a mean follow-up time of 3.1years. Plasma levels of IL-16 the day before surgery were analyzed by proximity extension assay (PEA) and associated with the occurrence of CV events during follow-up (n=98).

RESULTS: High levels of circulating IL-16 were independently associated with a decreased risk of CV events when comparing the highest versus the lowest IL-16 tertile (hazard ratio [HR] 0.47; 95% CI 0.27-0.81; P=0.007), as well as with CV deaths (HR 0.25; 95% CI 0.09-0.70; P=0.008).

CONCLUSION: These present findings indicate an association between IL-16 and less clinical complications of atherosclerosis in a population with known advanced carotid disease.