Browsing by Subject "South Africans"

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    A food-based dietary strategy lowers blood pressure in a low socio-economic setting: a randomised study in South Africa
    (2008) Charlton, Karen E; Steyn, Krisela; Levitt, Naomi S; Peer, Nasheeta; Jonathan, Deborah; Gogela, Theresa; Rossouw, Katja; Gwebushe, Nomonde; Lombard, Carl J
    OBJECTIVE: To assess the impact of a food-based intervention on blood pressure (BP) in free-living South African men and women aged 50-75 years, with drug-treated mild-to-moderate hypertension. METHODS: A double-blind controlled trial was undertaken in eighty drug-treated mild-to-moderate hypertensive subjects randomised to an intervention (n 40) or control (n 40) arm. The intervention was 8-week provision of six food items with a modified cation content (salt replacement (SOLO ), bread, margarine, stock cubes, soup mix and a flavour enhancer) and 500 ml of maas (fermented milk)/d. The control diet provided the same quantities of the targeted foods but of standard commercial composition and 500 ml/d of artificially sweetened cooldrink. FINDINGS: The intervention effect estimated as the contrast of the within-diet group changes in BP from baseline to post-intervention was a significant reduction of 6.2 mmHg (95 % CI 0.9, 11.4) for systolic BP. The largest intervention effect in 24 h BP was for wake systolic BP with a reduction of 5.1 mmHg (95 % CI 0.4, 9.9). For wake diastolic BP the reduction was 2.7 mmHg (95 % CI -0.2, 5.6). CONCLUSIONS: Modification of the cation content of a limited number of commonly consumed foods lowers BP by a clinically significant magnitude in treated South African hypertensive patients of low socio-economic status. The magnitude of BP reduction provides motivation for a public health strategy that could be adopted through lobbying of the food industry by consumer and health agencies.
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    Presisposing and protective HLA-DR and DQ alleles for rheumatoid arthritis in South African mixed-ancestry and Xhosa populations
    (2003) Rousseau, J; Pokorny, L; Glaser, J; Creemers, P C
    We have investigated the distribution of the HLA-DRB1, -DQA1 and -DQB1 alleles in rheumatoid arthritis (RA) by comparing the allele frequencies in blood from 65 Cape coloured (mixed-ancestry) RA patients and 114 controls, and from 25 Xhosa RA patients and 94 controls. The strongest positive association with RA was found for the DRB10401 allele, followed by the DQA10301 and DQB10302 alleles, which are strongly linked with DRB10401. Data for both populations were statistically significant. In addition, DQB10501, which is in linkage disequilibrium with DR1 and DR10, showed a positive association with RA. These findings are in agreement with those for Caucasoids; they indicate that haplotypes that predispose for RA are highly conserved during evolution. Negative associations, that is, a protective effect for RA, were also found, but only for broad specificities; the associations were generally weaker. New findings were negative associations for DRB103, DRB10701, DQA10501 and DQB106. The DRB10301 and DQA10501 alleles are in linkage disequilibrium; a negative association was found in both populations. The negative association of DRB10701 was found only in the mixed-ancestry population and was absent in Xhosa. The effect of DQA106 was significant in both populations. Thus, the protective HLA-DR and DQ alleles show a greater ethnic diversity.
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    South Africans' participation in local politics and government.
    (SAGE Publications, 2008) Mattes, Robert
    In this article, I use public opinion data collected over the past decade to probe three widely held assumptions about local government and public participation in South Africa. The first, widely held by advocates of political decentralisation and devolution of power, posits a direct relationship between the physical proximity of government institutions from the citizens they serve and the level of popular goodwill toward that government. However, public evaluations of local government have consistently been worse than those of either provincial or national government. Not only do people see local government as more corrupt than any other government institution, their levels of performance approval and trust in political institutions are inversely related to the proximal distance between them and that institution. The second assumption, widely held by advocates of ‘participatory democracy’, assumes that citizens have a natural predisposition to participate in public affairs. Accordingly, the participatory movement in South Africa has tended to define its central task as one of creating the mechanisms and forums for citizens to debate with each other and communicate with policy makers. However, citizen engagement with local government (measured in the form of individual contact with local councilors) is very low, both in absolute terms but also in relative terms compared to other African countries (though various pieces of evidence suggests that participation is increasing). Third, more recent analyses have assumed that low levels of voter turnout in local elections and increasing levels of public protest are a function of enduring poverty and inequality and growing dissatisfaction with service delivery. Yet analyses of individual participation in both local politics and government, and in protests and demonstrations, reveals that the poor are more likely to participate (rather than less), and that neither dissatisfaction nor satisfaction with local government performance provides an adequate account of this participation.