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Purpose: The renin-angiotensin-aldosterone system (RAAS) plays an important role in maintaining hemodynamic homeostasis. Ethnic disparities exist regarding RAAS activity due to sympathetic activity and sodium-water retention, however the implications thereof on cardiac damage is unknown. This study investigated the associations of cardiac troponin T (cTnT), N-terminal pro-brain natriuretic peptide (NTproBNP) and subclinical LVH with components of the RAAS (renin, aldosterone and aldosterone-to-renin ratio (ARR)) and copeptin in a black and white South African cohort. Materials and methods: The study population consisted of 305 participants (black = 139, white = 166) aged 20–62 years. Serum cTnT, NTproBNP, Cornell product, components of the RAAS (active renin, aldosterone and ARR) and copeptin were determined. Results: The black group had lower renin (p

Background and aims. Arterial hypertension doubles the risk of coronary heart disease, heart and kidney failure, and peripheral arterial disease. Less variation in diurnal ambulatory blood pressure monitoring (ABPM) patterns may affect mortality outcome. Therefore, as hypertension occurs in over 95% of older subjects, the prognostic value of dipping status in older hypertensive patients will be assessed. Method. The retrospective study group consisted of 170 hypertensive patients, aged 75 84 years, enrolled in the years 2005 to 2007. Baseline measures included 24-h ABPM. Diurnal index and dipping status was calculated and stratified the group into dippers (40 patients, 23.5%), non-dippers (65 patients, 38.2%) and reverse-dippers (65 patients, 38.2%). Results. During a 5-year observation, after baseline we have observed 69 deaths (40.9%) from the whole group of 170 patients with 23 (35.4%) being non-dippers and 36 (55.4%) reverse-dippers. There were significant differences between the groups divided according to diurnal dipping status in survival time, number of recorded deaths and night mean blood pressure. We have identified and confirmed risk factors for the all-cause mortality: age, mean systolic and diastolic blood pressure, diurnal index and dipping status (dipping, non-dipping or reverse-dipping). Conclusion. Reverse-dippers and non-dippers revealed worse prognosis compared with dippers.

Aim. Increased angiogenic factors [vascular endothelial growth factor-A (VEGF-A) and angiopoietin-2 (Ang-2)] have been associated with vascular dysfunction and hypertension. Black Africans undergoing rapid urbanization present with elevated blood pressure (BP) and we aimed to determine whether angiogenic factors are elevated in urban versus rural Africans with normal and elevated BP. Methods and Materials. Africans (n = 272), matched for gender and age, were recruited from rural and urban communities in South Africa. Omron HEM-757 BP data were obtained and angiogenic markers in plasma and serum were determined. Results. Urban African men displayed a higher (43.90%) hypertension prevalence compared with their rural counterparts (18.52%) and disturbed angiongenic factors. Adjusted VEGF-A concentrations were higher in urban men and women compared with their rural counterparts. Similar VEGF-A levels were observed in rural and urban hypertensives. Logistic regression analysis demonstrated that VEGF-A and Ang-2 levels were associated with psychosocial stress but not with hypertensive status in Africans [odds ratios 1.01–1.09 (95% CI 1.01–1.15), p ≤ 0.05]. Conclusion. Psychosocial stress per se was associated with disturbed VEGF-A and Ang-2. We suggest that hyperkinetic BP may act as compensatory mechanism when chronic psychosocial stress prevails, affecting vascular functioning and subsequent increased cardiovascular disease risk.