Cardiovascular disease is known as one of the leading causes of mortality worldwide, where low income countries or developing countries have the highest prevalence of cardiovascular disease. One of the main reasons for this statistics is acculturation that leads to changes in behavioral lifestyle and malnutrition within these countries. Low body mass index was found to be an independent risk factor for cardiovascular disease in several studies. From literature it is found that body mass index is lower than the ideal body mass index and is associated with cardiovascular disease. According to Higashi (2003) a body mass index of 22.2 kg/m2 is associated with the lowest morbidity. If body mass index decreases to lower values than the ideal body mass index, a J–curve will be evident suggesting higher prevalence of cardiovascular disease associated with low body mass index. These findings imply that not only high body mass index but also a low body mass index may be a risk factor for cardiovascular disease, morbidity and mortality. Whether low body mass index is associated with cardiovascular risk in an African population remains unclear. Objective: The aim of this study was to investigate the possible associations of low body mass index with variables of cardiovascular function in Africans, with a low socio–economic status. Methodology: This prospective cohort study (N= 2 010) is part of the Prospective Urban and Rural Epidemiology study (PURE) conducted in the North–West Province of South Africa in 2005, where the health transition in urban and rural subjects was investigated within an apparently low socio–economic status group. Our crosssectional PURE sub–study included 496 African people from rural and urban settings, (men, N= 252 and women, N= 244) aged between 35–65 years and body mass index lower than 25 kg/m2. Subjects were sub–divided into two groups. The first group consisted of Africans with a low body mass index smaller or equal to 20 kg/m2 (men; N= 152, women; N= 94) whilst the second group consisted of Africans with a normal body mass index larger than 20 kg/m2 and smaller or equal to 25 kg/m2 (men; N= 100, women; N= 150). Systolic blood pressure and diastolic blood pressure measurements were obtained with the validated OMRON HEM–757 device. The pulse wave velocity was measured using the Complior SP device. Blood was drawn by a registered nurse from the antebrachial vein using a sterile winged infusion set and syringes. Analyses for cholesterol, high density lipoprotein, triglycerides, gamma–glutamyl transferase and high sensitive C–reactive protein were completed utilizing the Konelab 20i. Data analyses were performed using the Statistica 10 program. Statistical analyses were executed to determine significant differences between age, body mass index and lifestyle factors as well as cardiovascular related variables in the different groups. T–tests were used to determine significant differences between independent groups. ANCOVA tests were used to determine BMI group differences independent of age, smoking and alcohol consumption. Partial correlations, which were adjusted for age, smoking and alcohol consumption, determined associations between the BMI groups and cardiovascular variables. Results: Our results indicated significantly higher mean values for the African men, with low body mass index, for cardiovascular variables (Diastolic blood pressure, 88.0 ± standard deviation (SD) 13.4 mmHg; mean arterial pressure, 103.8 ± SD 14.4 mmHg and carotid–radial pulse wave velocity, 12.6 ± SD 2.47 m/s) compared to the normal body mass index group (Diastolic blood pressure, 84.2 ± SD 12.2 mmHg; mean arterial pressure, 100.0 ± SD 13.2 mmHg and carotid–radial pulse wave velocity, 11.6 ± SD 2.00 m/s). The African women with low body mass index had a significant difference for carotid–radial pulse wave velocity (11.3 ± SD 2.43 m/s) compared to the normal body mass index group (10.6 ± SD 2.10 m/s). In African men, after the variables were adjusted for age, smoking and alcohol consumption, we revealed that diastolic blood pressure (88.0 with confidence interval (CI) [86.0– 90.0] mmHg) and carotid–radial pulse wave velocity (12.5 with CI [12.1–12.9] m/s) remained significant higher in the low body mass index group. Additionally, carotidradial pulse wave velocity was negatively associated with body mass index in African men. In the low body mass index group, Pearson and partial correlations of r= – 0.204; p= 0.012 and r= –0.200; p= 0.020 were found respectively in carotid–radial pulse wave velocity. Furthermore, in our unadjusted scatter plot with body mass index versus pulse wave velocity this negative trend of increasing carotid–radial pulse wave velocity with decreasing body mass index was noticeable in both African men and women. Even when carotid–radial pulse wave velocity was adjusted for age, smoking, alcohol consumption, mean arterial pressure and heart rate, a J–curve between carotid–radial pulse wave velocity and body mass index was still evident. Conclusion: A detrimental effect of low body mass index is evident on cardiovascular function in Africans. If body mass index decreases from the optimum value of 22.2 kg/m2 to lower values, a J–curve is evident between body mass index and cardiovascular variables suggesting higher prevalence of cardiovascular disease associated with low body mass index. In our sub–study the carotid–radial pulse wave velocity increases significantly in African men with low body mass index, thus supporting the theory that stiffening of the arteries is evident in Africans with a low body mass index. Low body mass index may contribute to the high prevalence of cardiovascular disease mortality within developing countries and therefore, increase the risk for cardiovascular disease. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2012.

Objectives: The aim of this study was to determine associations between physical activity (PA), blood pressure (BP) and renin in urban black Africans. Methods: The study sample included 137 urban African males (N=68) and females (N=69) (aged 41.53 ± 8.13 and 44.16 ± 7.37 years, respectively), from the North West Province, South Africa. Anthropometric measurements, ambulatory blood pressure and energy expenditure were determined. Actical® accelerometers were used to determine energy expenditure (METS) over a 24 hour period. Fasting blood samples were used to determine fasting blood glucose, serum cotinine (COT), gamma–glutamyl transferase (GGT) and plasma renin. Results: A greater percentage (64%) of African males were hypertensive compared to African females (33.33%). SBP (p<0.001) and DBP (p<0.001) were significantly higher in males than females. Female subjects were more obese (32.00±7.75 kg/m2) whereas males demonstrated an overweight status (27.28±5.86kg/m2). Male subjects displayed overall higher lifestyle risks (BP, smoking, alcohol consumption, HIV–status) than females. Multivariate regression analyses demonstrated an inverse relationship between BP and renin in both males and females, but no associations existed between renin and physical inactivity. Conclusion: PA appeared not to buffer elevated blood pressure in this specific African sample, as no significant associations supported this hypothesis. The results confirm that black Africans display lower renin levels associated with elevated blood pressure. Furthermore, low renin and physical inactivity was not related to indicate elevated BP through elevated SNS activity. / Thesis (M.Sc. (Biokinetics))--North-West University, Potchefstroom Campus, 2012.

Thesis (Ph.D. (Human Movement Science))--North-West University, Potchefstroom Campus, 2010.

Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2009.

Aim and objectives: This study set out to investigate the diet and blood lipid profiles of subjects in transition in the North West Province in South Africa. It looked specifically at how the diet differed between rural and urban areas, how the blood lipid profiles differed between rural and urban subjects, establishing an association between dietary fat, fatty acid and cholesterol intakes respectively and blood lipid profiles, as well as investigating the differences in blood lipid profiles at different ages, body mass index (BMI) and genders respectively in rural and urban areas. Design: The present study was a cross–sectional data analysis nested within the Prospective Urban and Rural Epidemiology (PURE) study that is currently undertaken in the North West Province of South Africa amongst other countries. Methods: Baseline data was obtained in 2005. A randomised paper selection was done of people between 35 - 70 years of age with no reported chronic diseases of lifestyle, TB or HIV of those enrolled into the PURE study if they had provided written consent. Eventually a paper selection was made of 2000 subjects, 500 people in each of the four communities (rural, urban–rural, urban, established urban). For the interpretation purposes of this study, data was stratified for rural (1000 subjects) and urban (1000 subjects) only, with no further sub–division into communities. Physical activity levels and habitual diets were obtained from these subjects. Demographic and dietary intake data in the PURE study was collected using validated, culture sensitive questionnaires. Anthropometric measures and lipid analysis were determined using standardised methodology. Descriptive statistics (means, standard deviations and proportions) were calculated. One–way analysis of variance (ANOVA) was used to determine differences between the different levels of urbanisation on blood lipid profiles and dietary intake. When a dietary intake variable proved to be significant for different levels of a factor (urbanisation, blood lipid profile), post–hoc tests were calculated to determine which levels for specific variables differed significantly. Bonferroni–type adjustments were made for the multiple comparisons. Spearman correlations were calculated to determine associations. Results: Mean fat intake was significantly higher in urban areas than in rural areas (67.16 ± 33.78 g vs. 32.56 ± 17.66 g, p<0.001); and the same was true for the individual fatty acid intakes. Fat and fatty acid intakes were still within recommendations even for urban areas, and low for rural areas. N–3 intake was very low in both rural and urban areas. Serum lipids did not differ significantly between rural and urban areas. Almost half of rural (43%) and urban (47%) subjects presented with elevated total cholesterol (5.0 mmol/L). In rural areas 52% and in urban areas 55% of subjects had elevated LDL–C (3.0 mmol/L). Amongst 23% of males in rural areas and 18% of males in urban areas HDL–C levels were decreased. Of the females living in rural areas 34.3% had decreased HDL–C levels and 39% of those who lived in urban areas presented with lowered HDL–C levels. In rural areas 16.3% of subjects and in urban areas 23% of subjects presented with high triglyceride levels. TC, LDL–C and triglyceride levels were higher in higher body mass index (BMI) classes, however, obese subjects did not differ significantly from overweight subjects in terms of blood lipids, suggesting that values stabilise after reaching overweight status. These blood lipids were also higher in higher age groups and higher in women than men, probably due to the high incidence of obesity in women. Conclusions: Associations between the diet and blood lipid profiles were weak, and diet is not likely to be the only factor responsible for high TC and LDL–C levels. Blood lipid profiles did not differ significantly between rural and urban areas due to the fact that the diet was prudent in terms of fat intake in both rural and urban areas. Higher prevalence of underweight was noted in males (32% in rural areas and 28% in urban areas), while overwieght was a bigger problem amongst women (48% in rural areas and 54% in urban areas). TC, LDL–C and TAG were higher with higher BMI’s, while HDL–C levels were lower. TC, LDL–C, and TAG were higher in higher age goups while HDL–C levels were lower. Female subjects presented with higher mean triglycerides than males, probably due to higher prevalence of overweight and obesity. / Thesis (M.Sc. (Dietetics))--North-West University, Potchefstroom Campus, 2011.

Cardiovascular disease is known as one of the leading causes of mortality worldwide, where low income countries or developing countries have the highest prevalence of cardiovascular disease. One of the main reasons for this statistics is acculturation that leads to changes in behavioral lifestyle and malnutrition within these countries. Low body mass index was found to be an independent risk factor for cardiovascular disease in several studies. From literature it is found that body mass index is lower than the ideal body mass index and is associated with cardiovascular disease. According to Higashi (2003) a body mass index of 22.2 kg/m2 is associated with the lowest morbidity. If body mass index decreases to lower values than the ideal body mass index, a J–curve will be evident suggesting higher prevalence of cardiovascular disease associated with low body mass index. These findings imply that not only high body mass index but also a low body mass index may be a risk factor for cardiovascular disease, morbidity and mortality. Whether low body mass index is associated with cardiovascular risk in an African population remains unclear. Objective: The aim of this study was to investigate the possible associations of low body mass index with variables of cardiovascular function in Africans, with a low socio–economic status. Methodology: This prospective cohort study (N= 2 010) is part of the Prospective Urban and Rural Epidemiology study (PURE) conducted in the North–West Province of South Africa in 2005, where the health transition in urban and rural subjects was investigated within an apparently low socio–economic status group. Our crosssectional PURE sub–study included 496 African people from rural and urban settings, (men, N= 252 and women, N= 244) aged between 35–65 years and body mass index lower than 25 kg/m2. Subjects were sub–divided into two groups. The first group consisted of Africans with a low body mass index smaller or equal to 20 kg/m2 (men; N= 152, women; N= 94) whilst the second group consisted of Africans with a normal body mass index larger than 20 kg/m2 and smaller or equal to 25 kg/m2 (men; N= 100, women; N= 150). Systolic blood pressure and diastolic blood pressure measurements were obtained with the validated OMRON HEM–757 device. The pulse wave velocity was measured using the Complior SP device. Blood was drawn by a registered nurse from the antebrachial vein using a sterile winged infusion set and syringes. Analyses for cholesterol, high density lipoprotein, triglycerides, gamma–glutamyl transferase and high sensitive C–reactive protein were completed utilizing the Konelab 20i. Data analyses were performed using the Statistica 10 program. Statistical analyses were executed to determine significant differences between age, body mass index and lifestyle factors as well as cardiovascular related variables in the different groups. T–tests were used to determine significant differences between independent groups. ANCOVA tests were used to determine BMI group differences independent of age, smoking and alcohol consumption. Partial correlations, which were adjusted for age, smoking and alcohol consumption, determined associations between the BMI groups and cardiovascular variables. Results: Our results indicated significantly higher mean values for the African men, with low body mass index, for cardiovascular variables (Diastolic blood pressure, 88.0 ± standard deviation (SD) 13.4 mmHg; mean arterial pressure, 103.8 ± SD 14.4 mmHg and carotid–radial pulse wave velocity, 12.6 ± SD 2.47 m/s) compared to the normal body mass index group (Diastolic blood pressure, 84.2 ± SD 12.2 mmHg; mean arterial pressure, 100.0 ± SD 13.2 mmHg and carotid–radial pulse wave velocity, 11.6 ± SD 2.00 m/s). The African women with low body mass index had a significant difference for carotid–radial pulse wave velocity (11.3 ± SD 2.43 m/s) compared to the normal body mass index group (10.6 ± SD 2.10 m/s). In African men, after the variables were adjusted for age, smoking and alcohol consumption, we revealed that diastolic blood pressure (88.0 with confidence interval (CI) [86.0– 90.0] mmHg) and carotid–radial pulse wave velocity (12.5 with CI [12.1–12.9] m/s) remained significant higher in the low body mass index group. Additionally, carotidradial pulse wave velocity was negatively associated with body mass index in African men. In the low body mass index group, Pearson and partial correlations of r= – 0.204; p= 0.012 and r= –0.200; p= 0.020 were found respectively in carotid–radial pulse wave velocity. Furthermore, in our unadjusted scatter plot with body mass index versus pulse wave velocity this negative trend of increasing carotid–radial pulse wave velocity with decreasing body mass index was noticeable in both African men and women. Even when carotid–radial pulse wave velocity was adjusted for age, smoking, alcohol consumption, mean arterial pressure and heart rate, a J–curve between carotid–radial pulse wave velocity and body mass index was still evident. Conclusion: A detrimental effect of low body mass index is evident on cardiovascular function in Africans. If body mass index decreases from the optimum value of 22.2 kg/m2 to lower values, a J–curve is evident between body mass index and cardiovascular variables suggesting higher prevalence of cardiovascular disease associated with low body mass index. In our sub–study the carotid–radial pulse wave velocity increases significantly in African men with low body mass index, thus supporting the theory that stiffening of the arteries is evident in Africans with a low body mass index. Low body mass index may contribute to the high prevalence of cardiovascular disease mortality within developing countries and therefore, increase the risk for cardiovascular disease. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2012.

Objectives: The aim of this study was to determine associations between physical activity (PA), blood pressure (BP) and renin in urban black Africans. Methods: The study sample included 137 urban African males (N=68) and females (N=69) (aged 41.53 ± 8.13 and 44.16 ± 7.37 years, respectively), from the North West Province, South Africa. Anthropometric measurements, ambulatory blood pressure and energy expenditure were determined. Actical® accelerometers were used to determine energy expenditure (METS) over a 24 hour period. Fasting blood samples were used to determine fasting blood glucose, serum cotinine (COT), gamma–glutamyl transferase (GGT) and plasma renin. Results: A greater percentage (64%) of African males were hypertensive compared to African females (33.33%). SBP (p<0.001) and DBP (p<0.001) were significantly higher in males than females. Female subjects were more obese (32.00±7.75 kg/m2) whereas males demonstrated an overweight status (27.28±5.86kg/m2). Male subjects displayed overall higher lifestyle risks (BP, smoking, alcohol consumption, HIV–status) than females. Multivariate regression analyses demonstrated an inverse relationship between BP and renin in both males and females, but no associations existed between renin and physical inactivity. Conclusion: PA appeared not to buffer elevated blood pressure in this specific African sample, as no significant associations supported this hypothesis. The results confirm that black Africans display lower renin levels associated with elevated blood pressure. Furthermore, low renin and physical inactivity was not related to indicate elevated BP through elevated SNS activity. / Thesis (M.Sc. (Biokinetics))--North-West University, Potchefstroom Campus, 2012.

The Caribbean, which is one of the most tourism-dependent regions of the world, is rich in cultural heritage, but it lacks developed and attractive cultural heritage sites. In particular, this is true for attractions that make use of the “dark” cultural heritage of the region which is associated with the Transatlantic Trade in Africans as slaves. This lack is seen as a major weakness in the region’s tourism product. This research explores the development of “dark” cultural heritage resources as attractions in the town of Falmouth, Jamaica, an 18th century port town that had a thriving economy during the peak period of British colonialism and the trade in Africans as slaves. Today, the economic importance of Falmouth is only a shadow of what it was during the infamous “glorious” days when sugarcane was “king and money in abundance” and Jamaica a leading sugar exporting colony was seen as a “jewel” in the English crown. A concurrent mixed method approach was used in the study where both qualitative and quantitative data from primary and secondary sources were collected and analysed. The methods that were used for data collection include questionnaire survey, semi-structured interviews, historical research and townscape survey. A systematic sampling technique was used to randomly select 100 households for a face-to-face questionnaire survey which achieved a 94% response rate. On the other hand, the purposive and snowball sampling methods were used to select twelve stakeholders for in-depth semi-structured interviews to ascertain their expectations and perspectives about the cultural heritage of the town. The textual data generated from the interviews were studied using content analysis, where substantive statements were identified from individual transcripts. Also, most appropriately, historical research was conducted to collect and evaluate historical information, such as written testimonies of eyewitnesses to events and also written accounts by person not immediately present at the time, but who obtained their description of events from someone else. In addition, a townscape survey was carried out to map, collect and evaluate data on a number of cultural heritage resources in Falmouth. It involved detailed field observation and the recording of the quality of townscape elements that are evaluated based on established criteria. Overall, the residents strongly supported tourism and argued for its development and expansion in Falmouth. They believed that the environmental, economic and socio-cultural benefits from tourism outweighed the negative implications of which they are fully aware. The data collection methods unearthed and confirmed that there is an abundance of dark cultural heritage in Falmouth that is associated with the Transatlantic Trade in Africans as slaves. Both tangible and intangible, highly rated cultural heritage resources were identified mainly in the Historic District. In all, twenty-seven cultural heritage resources and features that have the potential to be developed as attractions in support of a dark cultural heritage theme were identified, evaluated and catalogued. The major constraints to heritage development that were cited include: financial, psychological, absentee land owners, heritage designation’s restrictions, lack of consensus on developmental issues and some negative social perceptions. Residents and stakeholders suggested the following strategies to engage locals: sensitizing them to heritage development; providing them with information about opportunities as a result of the development; giving them practical information on ways to improve structures and restore buildings; providing them with information and education to build awareness about the cultural heritage of the town; and a public education campaign. Also, residents are amenable to: tour guiding, bed and breakfast operators, visitors’ service employees and involvement in planning conservation efforts. Residents attached a very high positive value to the cultural heritage resources of Falmouth even though they are aware that a lot of it is associated with the Transatlantic Trade. Such dark cultural heritage is deemed a significant part of the town’s heritage, so it is appropriate to use it for developing attractions for future generations where visitors can learn and be educated about the impact of the Transatlantic Trade. This position that the town should be developed as a destination where visitors can learn about slavery was supported by approximately 94% of the respondents to the questionnaire survey. Thus, the residents of Falmouth are motivated to tell the true story of the place. They unanimously are of the opinion that action should be taken to: promote Falmouth as a tourist destination, clean up and beautify Falmouth and provide job training for residents. Additional agreed and suggested actions include: infrastructure development; the development of educational awareness programmes; the development of heritage resources and related infrastructure; providing loans; grants and subsidies to building owners, building citizens’ awareness of cultural heritage and heritage programs; the provision of more entertainment facilities and activities; the development of Falmouth and addressing the cultural heritage of the town; A Master Plan is needed with a systematic way for its implementation along with the requisite funding; the implementation of a legislative framework to protect the town’s cultural heritage; the building of consensus among stakeholders; establishing a framework for the funding of restoration; engaging local and international organizations such as the JNHT and UNESCO; the sharing of plans at town-hall meetings; convene a meeting of all training agencies; and the development and implementation of a master plan. This research explored the development of Falmouth that has a “dark” and contested heritage, for sightseeing, learning and as an exemplary place for authentic experiences of identity for the African Diaspora. It will indeed help in the process to diversify Jamaica’s tourism product, contributes to the development of awareness and understanding of heritage at sensitive sites that are linked to humankind’s suffering and mass death. Finally, the study complements the UNESCO’s Slave Route Project that seeks to put an end to the historical silence on the African slave trade and slavery in general. The research concluded with a proposed planning framework for developing and promoting dark cultural heritage attractions.

Thesis (Ed. D.)--University of Toronto, 2004. / Adviser: David N. Wilson.

Thesis (Ph. D.)--University of Toronto, 2005.