Apolipoprotein B and interleukin 1 receptor antagonist: reversing the risk of coronary heart disease

Background Epidemiological evidence for the link of interleukin 1 (IL-1) and its inhibition with coronary heart disease (CHD) remains controversial. We aim to investigate the cardiovascular effects of IL-1 receptor antagonist (IL-1Ra) and underlying mechanisms, as well as the potential interaction with lifestyle factors. Methods A comprehensive multivariable Mendelian randomization study was performed. Genetic variants identified from a genome-wide association study involving 30,931 individuals were used as instrumental variables for the serum IL-1Ra concentrations. Genetic associations with CHD (60,801 cases and 123,504 controls) were extracted from the CARDIoGRAMplusC4D consortium. Inverse-variance weighted method was utilized to derive effect estimates, while supplementary analyses employing various statistical approaches. Results Genetically determined IL-1Ra level was associated with increased risk of CHD (odds ratio (OR), 1.07; 95% CI: 1.03-1.17) and myocardial infarction (OR, 1.13; 95% CI: 1.04-1.21). The main results remained consistent in supplementary analyses. Besides, IL-1Ra was associated with circulating levels of various lipoprotein lipids, apolipoproteins and fasting glucose. Interestingly, observed association pattern with CHD was reversed when adjusting for apolipoprotein B (OR, 0.84; 95%CI: 0.71-0.99) and slightly attenuated on accounting for other cardiometabolic risk factors. Appropriate lifestyle intervention was found to lower IL-1Ra concentration and mitigate the heightened CHD risk it posed. Conclusions Apolipoprotein B represents the key driver, and a potential target for reversal of the causal link between serum IL-1Ra and increased risk of CHD/MI. The combined therapy involving IL-1 inhibition and lipid-modifying treatment aimed at apolipoprotein B merit further exploration.