ABSTRACT
Alcohol consumption plays an important role in the health transition associated with urbanization in developing countries. Thus, reliable tools for assessing alcohol intake levels are necessary. We compared two biological markers of alcohol consumption and self-reported alcohol intakes in participants from urban and rural South African communities. This cross-sectional epidemiological survey was part of the North West Province, South African leg of the 12-year International Prospective Urban and Rural Epidemiology (PURE) study which investigates the health transition in urban and rural subjects. A total of 2,010 apparently healthy African volunteers (35 years and older) were recruited from a sample of 6,000 randomly-selected households. Alcohol consumption was assessed through self-reports (24-hour recalls and quantitative food frequency questionnaire) and by two biological markers: percentage carbohydrate-deficient transferrin (%CDT) and gamma-glutamyl transferase (GGT). Of the 716 men and 1,192 women volunteers, 64% and 33% respectively reported regular alcohol consumption. Reported mean habitual intakes of drinker men and women were 29.9 (±30.0) and 23.3 (±29.1) g of pure alcohol per day. Reported habitual intake of the whole group correlated positively and significantly with both %CDT (R=0.32; p≤0.01) and GGT (R=0.43; p≤0.01). The correlation between the two biomarkers was low (0.211; p≤0.01). GGT and %CDT values should be interpreted with care in Africans as self-reported non-drinker men and women had elevated levels of GGT (19% and 26%) and %CDT (48% and 38%). A need exists for a more specific biological marker for alcohol consumption in black Africans.
ABSTRACT
Objective: To examine the associations between measures of iron status and cardiovascular disease (CVD) risk factors in South African women.Method: In a cross-sectional study; demographic information and health history were obtained during individual interviews using validated questionnaires in the North West Province; South Africa. Anthropometric indices; iron indices; blood pressure; blood glucose and lipid profiles were measured using standard procedures in 1 262 apparently healthy black South African women aged 35 years or older. Iron status was assessed using serum concentrations of ferritin; transferrin receptor (TfR) and TfR:ferritin ratio.Results: Associations between iron status parameters and CVD risk factors were generally weak (r 0.3; p 0.01) and were not retained when adjustment was made for age; body mass index; smoking; alcohol consumption and C-reactive protein in the analysis. Waist circumference (WC) and waist:hip ratio (WHR) were higher in the fourth quartile of serum ferritin than in the third quartile; and also in the third quartile compared to the second quartile (P 0.05). Based on WC and WHR respectively; 31 and 52of the women had excess abdominal obesity. The mean (95 confidence interval) serum TfR concentration was high; at 9.09 ?g/ml (8.77; 9.44); indicating risk of iron deficiency. The mean (95 confidence interval) concentrations of lipids [total cholesterol 4.78 mmol/l (4.64; 4.93); high-density lipoprotein cholesterol 1.45 mmol/l (1.39; 1.52); low-density lipoprotein cholesterol 1.65 mmol/l (1.53; 1.78); triglyceride 1.12 mmol/l (1.07; 1.18)] were within reference ranges.Conclusion: No significant association was found between iron status parameters and established CVD risk factors. However; excessive abdominal adiposity indicated by high WC and WHR contributes significantly to increased serum ferritin concentration in this population