Troponin T release is associated with silent myocardial ischaemia in black men: The SABPA Study

Abstract

Background High sensitivity cardiac troponin T (hs-cTnT) is a validated marker of myocardial damage and may reflect the degree of silent myocardial ischaemia (SMI) and ventricular strain. Our aim was to compare hs-cTnT levels in black and white South Africans taking SMI into consideration. We further explored the capability of hs-cTnT to predict the presence of compensatory systolic hypertension in this South African cohort. Methods A bi-ethnic sex cohort ( n = 404) with similar socioeconomic status (198 black participants and 206 white participants, aged 20-65 years) participated in this target population study where 24 h ambulatory blood pressure, electrocardiogram and overnight fasting cardiometabolic variables were measured. Results Hypertension, higher glycated haemoglobin levels and more frequent and longer SMI events were observed more often in the black participants. Multivariate linear regression analysis showed positive associations between SMI events [Adj. R= 0.19; β 0.35 (0.08-0.62); p < 0.01], SMI event maximum duration [Adj. R= 0.17, β 0.43 (0.16-0.70), p < 0.01], SMI total duration [Adj. R= 0.12; β 0.37 (0.10; 0.65), p = 0.05] and hs-cTnT in black males only.] A lower hs-cTnT cut-point ≥4.2 pg/ml for 24 h systolic hypertension was predicted in the black participants compared with ≥5.6 pg/ml in the white participants (area under the curve 0.66-67 (95% CI: 0.57-0.75), p < 0.001) with a respective sensitivity/specificity of 64/68% and 61/71%. Conclusions hs-cTnT may be a potential marker of SMI in the prediction of systolic blood pressure increases, as well as clusters of risk factors for cardiovascular disease. Ethnic- and possibly sex-specific references values for hs-cTnT should be considered for risk stratification.

Chronic defensiveness and neuroendocrine dysfunction reflect a novel cardiac troponin T cut point: The SABPA study

“…Indeed, vascular resistance increases cardiac preload in essential hypertensives (Adefurin et al, 2013) and impeded coronary perfusion in a Black cohort (Griffiths et al, 2017).…”

BDNF increases associated with constant troponin T levels and may protect against poor cognitive interference control: The SABPA prospective study

“…Smith et al, (2014) supported this finding as BDNF was inversely associated with the development of atherosclerotic plaque in the carotid artery in the SABPA Blacks and in other studies . An impact on the microcirculation is suggested where downstream signalling of the carotid artery when atherosclerosis is present may induce inflammation and cortical ischaemia, a main stimulus for myocyte injury, and the release of cTnT . Myocyte injury also seems to be related to cognitive impairment .…”

“…4 44 a main stimulus for myocyte injury, and the release of cTnT. 45,46 Myocyte injury also seems to be related to cognitive impairment. 42 Upregulation of BDNF may thus be apparent in Black men to protect against myocardial injury and will also improve neurotrophin and cognitive health over a three-year period in Black men.…”

Editor’s Presentation

“…Troponin release is a well-known marker of myocardial injury. 10 In 33 healthy male amateur runners, aged around 50 years, marathon running was associated with transient but sharp and significant rises in the biomarkers of cardiovascular stress (hs-cTnI), which returned to baseline values after 2-4 days. Higher trained people showed lower rises.…”