Whether hypothyroidism is an independent risk factor for cardiovascular events is still disputed. We aimed to assess the association between hypothyroidism and risks of cardiovascular events and mortality. We searched PubMed and Embase from inception to 29 February 2016. Cohort studies were included with no restriction of hypothyroid states. Priori main outcomes were ischemic heart disease (IHD), cardiac mortality, cardiovascular mortality, and all-cause mortality. Fifty-five cohort studies involving 1,898,314 participants were identified. Patients with hypothyroidism, compared with euthyroidism, experienced higher risks of IHD (relative risk (RR): 1.13; 95% confidence interval (CI): 1.01–1.26), myocardial infarction (MI) (RR: 1.15; 95% CI: 1.05–1.25), cardiac mortality (RR: 1.96; 95% CI: 1.38–2.80), and all-cause mortality (RR: 1.25; 95% CI: 1.13–1.39); subclinical hypothyroidism (SCH; especially with thyrotropin level ≥10 mIU/L) was also associated with higher risks of IHD and cardiac mortality. Moreover, cardiac patients with hypothyroidism, compared with those with euthyroidism, experienced higher risks of cardiac mortality (RR: 2.22; 95% CI: 1.28–3.83) and all-cause mortality (RR: 1.51; 95% CI: 1.26–1.81). Hypothyroidism is a risk factor for IHD and cardiac mortality. Hypothyroidism is associated with higher risks of cardiac mortality and all-cause mortality compared with euthyroidism in the general public or in patients with cardiac disease.

Although Bone morphogenetic protein-2 (BMP-2) is a known mediator of bone regeneration and vascular calcification, to date no study has investigated the relationship between BMP-2 and type 2 diabetes mellitus (T2DM) and its possible role in coronary artery disease (CAD). The purpose of this study is to evaluate the relationship of BMP-2 with atherosclerosis and calcification in patients with T2DM. 124 subjects were enrolled in this study: 29 patients with T2DM and CAD; 26 patients with T2DM and without CAD; 36 patients with CAD and without T2DMand 34 without T2DM or CAD (control group). Severity of coronary lesions was assessed using coronary angiography and intravascular ultrasound (IVUS). Plasma BMP-2 levels were quantified using a commercially available ELISA kit. Compared to the control group, the mean plasma BMP-2 level was significantly higher in T2DM patients with or without CAD (20.1 ± 1.7 or 19.3 ± 1.5 pg/ml, vs 17.2 ± 3.3 pg/ml, P <0.001). In a multivariable linear regression analysis, both T2DM and CAD were significantly and positively associated with BMP-2 (Estimate, 0.249; standard error (SE), 0.063; p <0.0001; Estimate, 0.400; SE, 0.06; p <0.0001). Plasma BMP-2 was also strongly correlated with glycosylated hemoglobin A1c (HbA1c) (Spearman ρ = −0.31; p = 0.0005). SYNTAX score was also significantly associated with BMP-2 (Spearman ρ = 0.46; p = 0.0002). Using the results from IVUS, plasma BMP-2 levels were shown to positively correlate with plaque burden (Spearman ρ = 0.38, P = 0.002) and plaque calcification (Spearman ρ =0.44, P = 0.0003) and to negatively correlate with lumen volume (Spearman ρ =0.31, P = 0.01). Our study demonstrates that patients with T2DM had higher circulating levels of BMP-2 than normal controls. Plasma BMP-2 levels correlated positively with plaque burden and calcification in patients with T2DM.

MicroRNAs (miRNAs) have been shown to be associated with various physiological and pathological conditions, including inflammation and cardiovascular disease, but little is known about their relationship with the presence of coronary artery disease (CAD) and disease severity. A total of 195 consecutive subjects who underwent coronary angiography for chest pain evaluation were enrolled in this study. In CAD patients severity of coronary lesions was assessed by the number of diseased vessels and the Synergy between PCI with Taxus and Cardiac surgery score (SYNTAX score). Plasma levels of miRNA-145 were quantified by real-time quantitative polymerase chain reaction test, and logarithmic transformation of miRNA-145 levels (Ln_miRNA-145) was used for analyses due to its skewed distribution. Of the 195 total subjects 167 patients were diagnosed as having CAD. Ln_miRNA-145 was significantly lower in CAD patients compared with the non-CAD group (-6.11±0.92 vs. -5.06±1.25; p <0.001). In multivariable linear regression analyses CAD was significantly associated with lower Ln_miRNA-145 (Estimate, -0.50; standard error (SE), 0.11; p <0.0001). Furthermore, among CAD patients, three-vessel disease, higher SYNTAX scores and STEMI were significantly associated with lower Ln_miRNA-145 ([Estimate, -0.40; SE, 0.07; p <0.0001]; [Estimate, -0.02, SE, 0.10; p = 0.005] and [Estimate, -0.35, SE, 0.10; p <0.001] respectively). Lower plasma levels of miRNA-145 were significantly associated with the presence as well as severity of CAD. As a potential biomarker for CAD, plasma miRNA-145 may be useful in predicting CAD and its severity in patients presenting with chest pain.