Polymorphisms of the Interleukin-1β Gene Affect the Risk of Myocardial Infarction and Ischemic Stroke at Young Age and the Response of Mononuclear Cells to Stimulation In Vitro

Abstract

Objectives— To investigate the role of interleukin-1β (IL-1β) gene polymorphisms as a link between inflammation, coagulation, and risk of ischemic vascular disease at young age. Methods and Results— A total of 406 patients with myocardial infarction (MI) at young age, frequency-matched for age, sex, and recruitment center, with 419 healthy population-based controls and 134 patients with ischemic stroke at young age, matched by age and sex, with 134 healthy population-based controls, were studied. Subjects carrying the TT genotype of the −511C/T IL-1β polymorphism showed a decreased risk of MI (odds ratio [OR], 0.36; 95% CI, 0.20 to 0.64) and stroke (OR, 0.32; 95% CI, 0.13 to 0.81) after adjustment for conventional risk factors. In both studies, the T allele showed a codominant effect ( P =0.0020 in MI; P =0.021 in stroke). Mononuclear cells from volunteers carrying the T allele showed a decreased release of IL-1β and a decreased expression of tissue factor after stimulation with lipopolysaccharide compared with CC homozygotes. The presence of a monoclonal antibody against IL-1β during cell stimulation resulted in a marked reduction of tissue factor activity expression. Conclusions— -511C/T IL-1β gene polymorphism affects the risk of MI and ischemic stroke at young age and the response of mononuclear cells to inflammatory stimulation.