Association between plasma level of microRNA-21 and pulmonary hypertension in heart failure patients with preserved ejection fraction

AIM: To investigate the correlation between microRNA-21 (miR-21) and pulmonary hypertension(PH) in the patients with heart failure with preserved ejection fraction (HFpEF). METHODS: From January 2014 to February 2016, 102 HFpEF patients presenting to Jiangxi Provincial People's Hospital were enrolled in this study. The patients were divided into PH-HFPEF group (n=36, PASP ≥ 50 mmHg) and HFpEF group (n=40, PASP<50 mmHg). Another 36 age-and sex-matched subjects served as healthy controls. The plasma level of miR-21 and its correlations with clinic data were examined, and multivariate logistic regression analysis was performed to identify the independent predictors of PH-HFpEF. Receiver operating characteristic (ROC) curve was analyzed, and the area under the curve (AUC) was calculated. The sensitivity and specificity for PH-HFPEF diagnosis were also determined. RESULTS: Age, plasma endothelin-1 (ET-1), interleukin-6 (IL-6), brain natriuretic peptide (BNP) and left atrial diameter (LAD) were significantly higher in PH-HFPEF group than those in HFPEF group (P<0.05). The level of miR-21 was significantly increased in PH-HFPEF group compared with HFpEF group and healthy control group. In addition, the miR-21 level was correlated with PASP (r=0.267, P=0.000), plasma IL-6 (r=0.302, P=0.013) and left ventricular mass index (LVMI) (r=0.515, P=0.036). Plasma IL-6 was positively correlated with plasma ET-1 (r=0.622, P=0.002). PASP was positively correlated with plasma IL-6 (r=0.36, P=0.023), ET-1 (r=0.76, P=0.004), BNP (r=0.43,P=0.031), and LAD (r=0.39, P=0.044). ROC curve showed that the AUC of miR-21 was 0.80. Multivariate logistic regression analysis showed that miR-21, LAD and BNP were the independent predictors of PH-HFpEF. CONCLUSION: Increased plasma miR-21 level is positively correlated to PH-HFpEF, and is an independent predictor of PH-HFpEF, suggesting that plasma miR-21 might be a useful new biomarker for predicting PH in HFpEF patients.