Prospective Study on Plasma MicroRNA-4286 and Incident Acute Coronary Syndrome

Abstract

Background Mounting evidence suggests that circulating microRNAs (miRNAs) are critical indicators of cardiovascular disease. However, prospective studies linking circulating miRNAs to incident acute coronary syndrome (ACS) are limited, and the underlying effect of associated miRNA on incident ACS remains unknown. Methods and Results Based on a 2-stage prospective nested case-control design within the Dongfeng-Tongji cohort, we profiled plasma miRNAs from 23 pairs of incident ACS cases and controls by microarray and validated the candidate miRNAs in 572 incident ACS case-control pairs using quantitative real-time polymerase chain reaction. We observed that plasma miR-4286 was associated with higher risk of ACS (adjusted odds ratio according to an interquartile range increase, 1.26 [95% CI, 1.07-1.48]). Further association analysis revealed that triglyceride was positively associated with plasma miR-4286, and an interquartile range increase in triglyceride was associated with an 11.04% (95% CI, 3.77%-18.83%) increase in plasma miR-4286. In addition, the Mendelian randomization analysis suggested a potential causal effect of triglyceride on plasma miR-4286 (β coefficients: 0.27 [95% CI, 0.01-0.53] and 0.27 [95% CI, 0.07-0.47] separately by inverse variance-weighted and Mendelian randomization-pleiotropy residual sum and outlier tests). Moreover, the causal mediation analysis indicated that plasma miR-4286 explained 5.5% (95% CI, 0.7%-17.0%) of the association of triglyceride with incident ACS. Conclusions Higher level of plasma miR-4286 was associated with an increased risk of ACS. The upregulated miR-4286 in plasma can be attributed to higher triglyceride level and may mediate the effect of triglyceride on incident ACS.

Keywords: acute coronary syndrome; miR‐4286; microRNA; prospective study; triglyceride.

Figure 1. Associations of candidate miRNAs with incident ACS in the validation stage.

Plasma miRNA levels were normalized to miR‐26b‐5p and were expressed as 2^−∆Ct. Adjusted OR (95% CI) for incident ACS was obtained using multivariable conditional logistic regression model with adjustment for age, body mass index, smoking status, drinking status, education levels, metabolic equivalent, diabetes mellitus, hypertension, family history of coronary heart disease, high‐density lipoprotein cholesterol, low‐density lipoprotein cholesterol, triglyceride, and use of lipid‐lowering medication. P‐trend was estimated by assigning the median value of miRNA to each tertile and using this as a continuous variable in the logistic regression model. ACS indicates acute coronary syndrome; FDR, false discovery rate; IQR, interquartile range; miRNAs, microRNAs; and OR, odds ratio.

Figure 2. Associations of lipid traits with plasma miR‐4286 in the validation stage.

Forest plots of A, B, and C separately show the associations of lipid traits with plasma miR‐4286 among all participants, incident ACS cases, and controls. Adjusted PD (95% CI) for plasma miR‐4286 was obtained using multivariable linear regression model with adjustment for age, sex, body mass index, smoking status, drinking status, education levels, metabolic equivalent, and use of lipid‐lowering medication. P‐trend was estimated by assigning the median value of lipid to each tertile and using this as a continuous variable in the linear regression model. ACS indicates acute coronary syndrome; FDR, false discovery rate; HDL‐C, high‐density lipoprotein cholesterol; IQR, interquartile range; LDL‐C, low‐density lipoprotein cholesterol; PD, percent difference; TC, total cholesterol; and TG, triglyceride.

Figure 3. Causal effects of TG and HDL‐C on plasma miR‐4286.

The causal effect (95% CI) of TG and HDL‐C on miR‐4286 was estimated by Mendelian randomization analysis, using 39 TG SNPs and 58 HDL‐C SNPs derived from Asian reports, respectively. Pleiotropy P value derived from the intercept of MR‐Egger test or MR‐PRESSO Global test, a small P value indicates an unbalanced pleiotropy. HDL‐C, high‐density lipoprotein cholesterol; IVW, inverse variance‐weighted; SNPs, single nucleotide polymorphisms; and TG, triglyceride.

Figure 4. Mediation effects of plasma miR‐4286 on the associations of lipids with incident ACS.

A, Path diagram: Total effect (c)=direct effect (c′)+indirect effect (ab). B, Total effects and the proportion of mediation effects were obtained by quasi‐Bayesian Monte Carlo simulation for 10 000 times in the R package “mediation.” Indirect effects were derived from multiple linear regression for the association of lipid with miRNA level adjusting for age, sex, body mass index, smoking status, drinking status, education levels, metabolic equivalent, and use of lipid‐lowering medication. Direct effects were calculated by logistic regression for the association of lipid with ACS additional adjusting for miRNA level, diabetes mellitus, hypertension, family history of coronary heart disease, and low‐density lipoprotein cholesterol. ACS indicates acute coronary syndrome; HDL‐C, high‐density lipoprotein cholesterol; miRNA, microRNA; and TG, triglyceride.