Hypertension is associated with end organ damage (EOD). Since EOD is a risk factor for cardio- and cerebrovascular complications, it is a major requirement for these to be detected, prevented and treated. A total of 147 consecutive patients with newly-diagnosed essential hypertension and attending the outpatient clinic were included in this study based on a set of inclusion and exclusion criteria (patients with co-morbid illnesses were excluded from the investigation). Among them, 86% (70 male (M) and 56 female (F)) had one or more EODs, an observation which was very close to statistically significance (P=0.054). The presence of one or more EODs in newly-detected hypertension indicates widespread vascular damage which carries the high risk for cardio- and cerebrovascular morbidity and mortality. Although thyroid dysfunctions exert significant effects on blood pressure (BP), published literature available has revealed contradictory data. Objective of our study was to explore the inter-relationships between selected thyroid dysfunctional status (hyper and hypothyroid) and established biomarkers [thyroid stimulating hormone (TSH) and thyroxine (T4)]; and BP components [specifically Systolic BP (SBP), Diastolic BP (DBP), and Mean Arterial Pressure (MAP), and uniquely SBP:DBP ratio]. We followed rigid criteria in order to select adults with hyperthyroidism (n=71) and hypothyroidism (n=300), together with healthy age-matched controls (n =300), and applied a series of statistical analyses on the datasets acquired. We have observed thyroid dysfunctional status is associated with elevated BP, and increasing BP is positively-correlated with elevated serum thyroid biomarkers, hyper and hypothyroid disorders should be recognized and treated early in order to avoid critical hazards presented by high BP. Also, we have studied awareness among public and physicians in managing hypertension. Overall, the levels of knowledge and awareness among both groups are sub-optimal. Hence there is an urgent need for empowerment among both groups to enhance awareness and to bring effective standard of care.

Motivation: Recently, with urbanisation becoming an increasing trend, the African population have been introduced to the westernised lifestyle. This contributed to severe health implications and a rapid increase in cardiovascular morbidity and mortality in the African population. In South Africa and other sub–Saharan African countries, the prevalence of cardiovascular disease is increasing rapidly. The African population is thus regarded as a high risk group, and we deem it necessary and important to investigate additional possible cardiovascular risk markers in the attempt to improve the diagnosis of cardiovascular diseases and the treatment thereof. We investigate double product as a possible cardiovascular risk marker in African and Caucasian men from South Africa. Recent studies have suggested that increased double product values might be an independent predictor of cardiovascular morbidity and mortality. However, investigations on double product and endorgan damage are limited in this population group. The strength of associations between double product and various measurements of end–organ damage, including intima–media thickness, left ventricular hypertrophy and albumin–to–creatinine ratio, are compared with the associations between the more traditional risk factor, systolic blood pressure, and the measurements of end–organ damage. Aim: The aim of this study is to investigate the usability of double product as a possible cardiovascular risk marker in African and Caucasian men from South Africa. Methodology: The manuscript presented in Chapter 3 made use of the cross–sectional SABPA (Sympathetic Activity and Ambulatory Blood Pressure in Africans) study, where 101 urbanised African and 101 Caucasian male school teachers from the North West Province of South Africa were recruited. Anthropometric measurements were taken in triplicate using standard methods. The cardiovascular measurements included 24–hour ambulatory blood pressure and electrocardiogram measurements. Double products were calculated as the product of 24–hour, daytime and night–time mean systolic blood pressure and mean heart rate values. The carotid intima–media thickness was also obtained following the prescribed protocols. A registered nurse collected blood samples and the biochemical measurements were performed by independent laboratories, blinded to the subject’s cardiovascular profile. Means and proportions were compared by standard t–tests and the x2 –tests, respectively. The association between markers of end–organ damage and double product were investigated using single, partial and multiple regression analyses. All p–values <= 0.05 were deemed significant. Results and conclusions: Results from this study showed that Africans displayed significantly higher systolic blood pressure values, heart rate values and subsequent double product values compared to the Caucasians. Despite these significant differences, double product only showed borderline significant correlations with the markers of end–organ damage in African men, while no correlations were evident in Caucasian men. In African men, systolic blood pressure displayed stronger and significant correlations with intimamedia thickness, left ventricular hypertrophy, and albumin–to–creatinine ratio than double product. These findings suggest that double product may not be a good marker of increased risk for end–organ damage and subsequent cardiovascular–related mortality. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2011.

Motivation: Recently, with urbanisation becoming an increasing trend, the African population have been introduced to the westernised lifestyle. This contributed to severe health implications and a rapid increase in cardiovascular morbidity and mortality in the African population. In South Africa and other sub–Saharan African countries, the prevalence of cardiovascular disease is increasing rapidly. The African population is thus regarded as a high risk group, and we deem it necessary and important to investigate additional possible cardiovascular risk markers in the attempt to improve the diagnosis of cardiovascular diseases and the treatment thereof. We investigate double product as a possible cardiovascular risk marker in African and Caucasian men from South Africa. Recent studies have suggested that increased double product values might be an independent predictor of cardiovascular morbidity and mortality. However, investigations on double product and endorgan damage are limited in this population group. The strength of associations between double product and various measurements of end–organ damage, including intima–media thickness, left ventricular hypertrophy and albumin–to–creatinine ratio, are compared with the associations between the more traditional risk factor, systolic blood pressure, and the measurements of end–organ damage. Aim: The aim of this study is to investigate the usability of double product as a possible cardiovascular risk marker in African and Caucasian men from South Africa. Methodology: The manuscript presented in Chapter 3 made use of the cross–sectional SABPA (Sympathetic Activity and Ambulatory Blood Pressure in Africans) study, where 101 urbanised African and 101 Caucasian male school teachers from the North West Province of South Africa were recruited. Anthropometric measurements were taken in triplicate using standard methods. The cardiovascular measurements included 24–hour ambulatory blood pressure and electrocardiogram measurements. Double products were calculated as the product of 24–hour, daytime and night–time mean systolic blood pressure and mean heart rate values. The carotid intima–media thickness was also obtained following the prescribed protocols. A registered nurse collected blood samples and the biochemical measurements were performed by independent laboratories, blinded to the subject’s cardiovascular profile. Means and proportions were compared by standard t–tests and the x2 –tests, respectively. The association between markers of end–organ damage and double product were investigated using single, partial and multiple regression analyses. All p–values <= 0.05 were deemed significant. Results and conclusions: Results from this study showed that Africans displayed significantly higher systolic blood pressure values, heart rate values and subsequent double product values compared to the Caucasians. Despite these significant differences, double product only showed borderline significant correlations with the markers of end–organ damage in African men, while no correlations were evident in Caucasian men. In African men, systolic blood pressure displayed stronger and significant correlations with intimamedia thickness, left ventricular hypertrophy, and albumin–to–creatinine ratio than double product. These findings suggest that double product may not be a good marker of increased risk for end–organ damage and subsequent cardiovascular–related mortality. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2011.