Plasma fibrinogen of black South Africans: the BRISK study.

OBJECTIVE: To describe the distribution of plasma fibrinogen and relationships with other risk factors for coronary heart disease (CHD) and stroke in the black population of the Cape Peninsula. DESIGN: A cross-sectional survey of a stratified proportional sample of randomly selected black men and women. SETTING: Households in Gugulethu, Langa, Nyanga, New Crossroads, KTC, Old Crossroads and Khayelitsha in the Cape Peninsula, South Africa. SUBJECTS: One subject per household (352 men and 447 women), aged 15-64 years, voluntarily participated. Visitors, pregnant, lactating, ill, mentally retarded and intoxicated subjects were excluded. RESULTS: Mean fibrinogen (thrombin time coagulation method) of men and women were higher than published data for Europeans but slightly lower than values of black Americans. Women aged 45-54 years had the highest level (3.13+/-0.89 g l(-1)) and men aged 15-24 years had the lowest (2.13+/-0.88 g l(-1)). Fifteen per cent of the men and 12% of the women had a level greater than 1 standard deviation of the mean for their age group. Univariate and multivariate analyses revealed significant (P<0.05) positive correlations of fibrinogen with smoking habit, age, body mass index (BMI), total and low-density lipoprotein (LDL) cholesterol, triglycerides, blood pressure and white blood cell count, and significant negative correlations with high-density lipoprotein (HDL) cholesterol, gamma glutamyl transferase (GGT), serum iron and ferritin. The correlations with BMI, serum lipoproteins, iron, ferritin, and GGT suggest that nutritional status and therefore diet influences plasma fibrinogen. CONCLUSION: Relatively high fibrinogen levels, tending to cluster with other, including diet-related, risk factors for CHD and stroke, were observed in black South Africans. It is suggested that fibrinogen may contribute to the high stroke incidence of this population group.

The haematological profile of urban black Africans aged 15-64 years in the Cape Peninsula.

A stratified probability sample (n = 986) with quotas was drawn from black residential areas in the Cape Peninsula, South Africa. Subjects (n = 819) aged 15-64 years, participated in a coronary heart disease (CHD) risk factor survey, the BRISK Study. Nutritional status and prevalence of CHD was determined in this population undergoing rapid urbanization. Full blood and differential white blood cell counts provided data to calculate population reference values based on the 95% reference limits of the haematological parameter. Mean haemoglobin concentrations (Hb) in men (14.0 g/dl) and women (12.4 g/dl) were +/- 1.5 g/dl lower than previous South African reports. Mean BRISK Hb values were very similar to the World Health Organization's Hb cutoff criteria (< 13 g/dl men; < 12 g/dl women), indicating a possible high prevalence of anaemia. Significantly higher (P < 0.05) mean values for red cell indices were confirmed in men, which also reflected equally higher red blood cell counts (RBC), haematocrit (HCT) and mean corpuscular haemoglobin (MCH) values. Mean Hb values were significantly lower in the younger (15-24 years) and older (55-64 years) men compared with 25-54 year-olds (P < 0.05). Hypochromic microcytic anaemia was more prevalent in women, possibly due to iron deficiency (ID), while macrocytic anaemia was more prevalent in men. No significant differences were noted in mean total and differential white blood cell counts (WBC) between men and women.(ABSTRACT TRUNCATED AT 250 WORDS)

Dietary patterns and nutritional status in free-living older white men with established vascular disease.

Thirty-nine white men aged 51-84 years with established vascular disease were studied to investigate the effect of fish oil capsules on the regression of these lesions. This article deals with the baseline data of the study. The subjects completed a 7-day dietary record, weight and height were measured and a fasting blood sample was analysed for proteins, haematological values and certain vitamins. Dietary analysis indicated that the mean energy intake was 8,552 kJ (SD = 2,095). The energy distribution was 15.5% protein, 33.6% fat and 46.4% carbohydrate. In the light of the recommended dietary allowances the diet was lacking in zinc, vitamin B6 and folic acid, which suggests that the subjects might be deficient in these micronutrients. Although the diets were lacking in these nutrients, no clinical stigmata were observed. The subjects averaged a body mass index of 26.1 and could therefore be classified as overweight. The mean haematological values as well as the plasma vitamins were within the normal range. In conclusion it can be said that the men consumed a diet that was too high in fat and that the diet lacked certain micronutrients.

Increased production of prostacyclin after injury to the microvasculature in uraemic patients.

A recently described method to evaluate the primary haemostatic mechanism under in vivo conditions was utilised to investigate thromboxane A2 (TXA2) and prostacyclin (PGI2) production by platelets and vascular endothelial cells, respectively, in patients with severe chronic renal failure. Unlike some previous studies, a decrease in TXA2 production by uraemic platelets could not be demonstrated. PGI2--produced by microvascular endothelial cells after a standardised injury--was, however, 59% higher in patients than controls (P less than 0.05). An increased local level of this potent platelet inhibitory eicosanoid could play an important role in the bleeding tendency exhibited in chronic renal failure.