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Objective: To determine the prevalence of some risk factors of coronary heart disease (CHD) in a rural Nigerian population., Design: Prospective cross-sectional study., Setting: Three villages around Maiduguri in the north eastern part of Nigeria., Subjects: Five hundred randomly selected subjects, consisting of 278 males and 222 females., Intervention: Anthropometric parameters such as weight, height, body mass index and blood pressure were measured. Also fasting blood concentration of glucose, total cholesterol (Tc) and high density cholesterol (HDL-c) were measured., Main Outcome Measures: The various parameters were compared between males and females., Results: Prevalence of hypercholesterolaemia was zero because no subjects had values greater than 5.2 mmol/1. Overall prevalence of obesity was 2%, with 1.2% in males and 3.2% in females. High blood pressure was observed in 15.2% of the subjects, with it being more among males (19.1%) than females (10.3%). Mean fasting blood glucose was significantly higher (p < 0.01) in females (6.2 mmol/1) than males (4.2 mmol/1). Prevalence of diabetes mellitus was 2.6% and being higher among females., Conclusion: Our results demonstrated lower prevalence of obesity and hypertension when compared with earlier results from the southern part of Nigeria, but showed an increase in the prevalence of diabetes mellitus. We therefore recommend that a survey of CHD risk factors should be carried out in different ethnic groups.

The levels of complement components C3 and C4 were determined in EDTA (ethylene-diamine-tetra-acetic acid) plasma of 106 apparently healthy people aged 11-50 years, and in 23 paired maternal and cord plasma in Ilorin. The immunoglobulins G,A and M concentrations of these paired samples were also assayed. Furthermore, serum IgG, IgA and IgM levels were quantitated in 501 apparently healthy residents of Ilorin (1-84 years old, n = 313) and its suburban community, Shao (11-80 years old, n = 188). Generally, there were no significant sex-related differences in C3 and C4 values, but these values increased steadily with age. C3 and C4 levels in cord plasma were high, representing 73% and 88% of adult levels respectively. Maternal levels of these complement components were higher (P < 0.02) than values obtained in non-pregnant females of comparable age. Immunoglobulin G values obtained for maternal and cord samples compare well with figures reported previously from other centres in Nigeria. Only 1 of 23 IgA and 2 of 23 IgM samples showed detectable values of these immunoglobulins in cord blood. The mean concentrations of immunoglobulins obtained were similar for IgG and lower for IgA and IgM in Ilorin, but higher for IgG and lower for IgA and IgM in Shao, when compared with data reported from Enugu and Zaria--both in Nigeria. Shao showed significantly higher mean level of IgG but similar levels of IgA and IgM to values obtained in Ilorin. Generally, IgG and IgA concentrations rose gradually up to age group 31-40 and 41-50 years respectively; and then declined. (ABSTRACT TRUNCATED AT 250 WORDS)

Plasma cholesterol was measured in 417 healthy rural Nigerians consisting of 230 males (mean age 36.60 +/- 1.29 years) and 187 (mean age 34.60 +/- 1.38 years). Mean plasma cholesterol concentrations were found to be 2.91 +/- 0.22 mmol/l and 3.26 +/- 0.25 mmol/l in males and females respectively. These differences were highly significant (p < 0.025). The lowest plasma cholesterol levels were observed in the 11 to 20 year age group and the highest in the > 61 years age group. A strong correlation, which was higher in males than females was observed between plasma cholesterol and age (r = 0.48; p < 0.01). No significant correlation was observed between body mass index (BMI) and plasma cholesterol in both male female subjects. These results suggest that plasma cholesterol concentrations observed in rural Nigerians may be related to their physical activity and the consumption of a low fat diet.

The effect of the oral slow-release formulation of Nifedipine in rapidly lowering blood pressure was studied in 20 severely hypertensive Nigerians (8 males, 12 females). A significant fall (p < 0.05) in mean systolic, diatolic, and mean arterial pressure was obtained 30 minutes after administration of Nifedipine. The fall in all three parameters of blood pressure remained sustained and significant (p < 0.05) 6 hours after a single dose administration. Side effects were minimal and limited to headaches in 20% of patients and palpitations in 10%. All patients showed a sustained control of blood pressure over a three month follow up period on slow release Nifedipine. Addition of methyldopa resulted in improved blood pressure control in one patient with chronic renal failure. It was concluded that oral slow release Nifedipine is a drug of choice in the rapid and sustained control of blood pressure in severely hypertensive patients especially in a setting where critical intensive monitoring facilities are limited.

Detection of measles specific IgG in serum was done on 618 samples obtained from Nigerians (aged 11 years or more) resident in Ilorin (urban) and Shao (a suburban outlay of Ilorin). An enzyme-linked immunosorbent assay (ELISA) method was used. Eighty-six percent of the sampled population had detectable antibody levels. Significant differences were found between positivity rates in the two locations studied and between the sexes in the urban samples.

Derangements in plasma lipids and lipoproteins have been observed in Caucasian diabetics with retinopathy, a major microvascular complication of diabetes mellitus. The role of plasma lipids and lipoprotein in the development of diabetic retinopathy is not clear and its alteration in black Africans has not been investigated. Fasting plasma cholesterol, triglyceride and HDL-cholesterol concentrations were estimated in 27 Type II (non insulin-dependent) Nigerian diabetics with retinopathy and 37 without retinopathy and 63 healthy subjects. Both diabetic subgroups were comparable regarding their blood glucose control, body mass index and duration of diabetes. Plasma lipid and lipoprotein concentrations were similar in each group of patients, with no significant differences in diabetics with and without retinopathy. Plasma lipids and lipoproteins were not affected by the duration of the diabetic state. These results suggest that diabetic retinopathy in Nigerians is not associated with significant alteration in the concentration of plasma lipids and lipoproteins.

Plasma lipids and lipoproteins were measured in 24 Nigerians with the nephrotic syndrome and 29 healthy subjects. None of the patients had been commenced on treatment. Plasma total cholesterol, low density lipoprotein (LDL) cholesterol group (P less than 0.005). By contrast, the HDL-cholesterol to total cholesterol ratio as well as the HDL-cholesterol concentrations were found to be significantly lowered in the nephrotics than the controls (P less than 0.005). A strong correlation was observed between plasma total cholesterol and LDL cholesterol values but not between the other biochemical parameters (r = 0.98.P less than 0.01). These results, though not definitive, suggest that Nigerians with the nephrotic syndrome may represent a risk group for the development of ischaemic heart disease. Long term prospective studies in such patients are desirable to define the effect of these lipid and lipoprotein abnormalities.

Erythrocyte and plasma magnesium concentrations were measured in 168 subjects. Eighty three of the subjects were sickle-cell anaemia patients (sicklers) with haemoglobin genotype HbSS, and in the steady state; 30 were subjects who had the sickle-cell trait (HbAS), and 55 were subjects with the normal haemoglobin genotype HbAA. All the subjects were aged between 10 and 16 years. The sicklers had significantly lower erythrocyte (P less than 0.01) concentrations when compared with the normal subjects or subjects with the sickle-cell trait. Erythrocyte and plasma magnesium concentrations in subject with the sickle-cell trait were not significantly different from the corresponding values in the normal subjects. A significant negative correlation (r = -0.2661, P less than 0.02) was observed between erythrocyte magnesium and plasma magnesium in the sicklers only. However, magnesium concentrations in erythrocyte and plasma were not related to age, sex and physical stature in the three study groups. These results suggest that sickle-cell anaemia patients may be magnesium deficient.

Plasma lipids and lipoproteins were estimated in 67 Nigerian children (mean age 10.19 years) with sickle cell anaemia (HbS) and 67 age- and sex-matched non-anaemic controls with normal haemoglobin (HbA). Plasma cholesterol and HDL-cholesterol levels were significantly lower while the plasma triglyceride level was significantly higher in the subjects with sickle cell anaemia. LDL-cholesterol levels were higher in sickle cell anaemia patients, but were not of statistical significance. These results do not support suggestions that sickle cell anaemia patients are at low risk of developing coronary artery disease.

Observations in Caucasian diabetics have linked hypomagnesaemia as being an additional risk factor for the development of retinopathy which is a major microvascular complication of diabetes mellitus. We estimated fasting plasma magnesium concentrations in 82 non-insulin-dependent Nigerian diabetics with normal renal function and 48 healthy subjects. The diabetic patients were divided into two subgroups according to the presence (n = 25) or absence (n = 57) of retinopathy. Both diabetic subgroups were comparable regarding their metabolic control, body mass index and duration of diabetes. Hypomagnesaemia was observed in the diabetic patients as a whole and in the diabetic subgroups with and without retinopathy; however these levels were not of statistical significance when compared to healthy controls. Furthermore, when the two diabetic subgroups were compared, no significant differences were observed in the magnesium concentrations. Our data suggests that hypomagnesaemia may not be associated with the occurrence of retinopathy in black African diabetics.

A study of the patterns of fasting plasma magnesium concentration in 92 Nigerians diabetics (comprising 68 non insulin dependent and 24 insulin dependent) and 30 healthy controls was undertaken. In all diabetics taken as a whole and in insulin dependent and non-insulin dependent diabetics considered separately, plasma magnesium concentrations were lower compared to healthy controls but these differences were not statistically significant. There were no significant differences in magnesium levels between male and female diabetics. No significant correlation was observed between fasting plasma magnesium and fasting plasma glucose concentrations. Furthermore plasma magnesium concentrations were not affected by the degree of blood glucose control. Plasma magnesium concentrations did not correlate with age and duration of diabetes. It is suggested that the observed lack of significant hypomagnesaemia even among poorly controlled diabetics may be a protective factor against the development of ischaemic heart disease and of retinopathy in black African diabetics.

Total cholesterol, triglyceride and HDL-cholesterol concentrations were measured in 49 non-insulin-treated Nigerian diabetics and 40 healthy controls. Low levels of HDL-cholesterol were observed in the diabetic group (n = 49) and in both male (n = 20) and female (n = 29) diabetics, but these low levels were of significance in female diabetics only (p less than 0.025) and in the diabetic group considered as a whole (p less than 0.05). Significant hypertriglyceridaemia was observed in the diabetic group (p less than 0.005) and in both male (p less than 0.025) and female (p less than 0.05) diabetics. Total cholesterol concentrations were higher in each of the diabetic groups but these differences were not significant. These results suggest that black African diabetic females may represent a high risk group for development of other long term complications of diabetes mellitus and should therefore be monitored.

The results of a prospective study of the prevalence of diabetic retinopathy among Nigerian diabetics attending a Nigerian Teaching Hospital over a one and a half-year period are presented. Diabetics with mature cataracts whose fundi could not be visualised were excluded from the study. 15.1% of the 377 diabetic patients included in the study group had changes consistent with diabetic retinopathy. The prevalence was found to increase with increasing duration of disease, being 12.7%, 16.8% and 20.0% in patients with duration less than 5 years, between 5 and 10 years and greater than 10 years respectively. A considerably higher prevalence was also found in the insulin treated diabetics compared to the non insulin treated group (P less than 0.05). The degree of glycaemic control appeared to be poorer in the diabetics with retinopathy compared to those without, even though the differences between the mean fasting plasma glucose concentrations between the two groups did not reach statistical significance. Proteinuria was found to be significantly commoner in diabetics with retinopathy (P less than 0.025). It was concluded that diabetic retinopathy is on the increase among Nigerians and that efforts should be directed at evolving preventive measures and early identification of high risk patients.

Erythrocyte and fasting plasma magnesium were assayed by a dyebinding colorimetric method using the metallochromic dye, Calmagite, in 51 diabetic Nigerians and 25 controls. Erythrocyte magnesium concentrations were similar in the diabetics and the controls. Fasting plasma magnesium concentrations were significantly lower only in insulin-treated diabetics as compared to controls. No significant correlations were observed between fasting plasma glucose concentrations and either plasma or erythrocyte magnesium concentrations in the diabetic groups. Also, no significant correlation was found between erythrocyte magnesium and plasma magnesium concentrations. However, erythrocyte magnesium concentrations were directly related to age while plasma magnesium concentrations were directly related to duration of diabetes in all diabetics. Erythrocyte and plasma magnesium concentrations were not significantly affected by sex and degree of plasma glucose control. These results suggest that insulin-treated black African diabetics may develop hypomagnesaemia which is not associated with depletion of the erythrocyte content of magnesium.