|dc.description.abstract||Background: In South Africa, as in many other developing countries, iron deficiency (the
most common micronutrient deficiency) still remains unresolved; while obesity has
emerged as a public health challenge causing increases in the incidence and prevalence of
cardiovascular diseases (CVDs). Research has shown that certain iron indices are
associated with both anthropometric and biological markers of CVDs. Adiposity is
thought to modulate the pathway linking iron status to CVDs.
Objective: To examine the associations between iron indices, anthropometric and
biological markers of CVDs in an African population undergoing transition.
Methods: This thesis was based on secondary analysis of data generated during the
Transition and Health during Urbanisation of South Africans (THUSA) study; and
primary and secondary analysis of the baseline Prospective Urban and Rural
Epidemiological (PURE) study. Both studies were cross–sectional in design and were
conducted between 1996–1998 and in 2005 respectively in the North West Province of
South Africa. The 1854 men and women participants in the THUSA study (>15years)
and 1262 women participants in the PURE study (>35years) were included in the
analysis. The relationship between iron and anthropometric indicators of CVD risk was
examined in the THUSA study while that of iron status, anthropometric and biological
markers of CVD risk was examined in the PURE study.
Results: In the THUSA study, ferritin was positively associated with body mass index
(BMI), waist circumference (WC), waist to hip ratio (WHR), body fat and subscapular
skinfold (r=0.141, 0.359, 0.396, 0.308, 0.141 respectively for men and 0.126, 0.232,
0.319, 0.126, 0.105 respectively for women; p<0.01). Only the women showed decreased
serum iron concentration with increasing BMI (p<0.05). WC and WHR increased with
increasing serum ferritin concentration for both genders (p<0.05). As for the PURE
study, associations between iron status parameters and CVD risk factors were generally
weak (r<0.3, p<0.01) and were not retained after adjusting for valid confounders. WC
and WHR increased with increasing ferritin concentration (p<0.05).
Conclusion: Although these results do not indicate any significant association between
iron indices and biological markers of CVD, its association with anthropometric indices
gives an indication of the possible contribution of iron in the aetiology of CVDs. Thus, it may be necessary to exercise caution on the emphasis placed on iron as a nutrient and
iron intervention programmes because of the suggestive role of iron in CVD