High density lipoprotein cholesterol as a determinant factor in coronary heart disease in Africans
Adebonojo, S.A.; Ogunnaike, H.O.
Journal of the National Medical Association 81(5): 547-556
1989
ISSN/ISBN: 0027-9684 PMID: 2746678 Document Number: 332306
A study of the lipid profile of 200 normal Nigerian subjects (Group A) shows a steady increase in the total cholesterol and triglyceride values with increasing age in both sexes, while the high density lipoprotein (HDL) cholesterol and percent HDL cholesterol values show a steady decrease with increasing age in both sexes. A similar study of 160 patients with high-risk factors (Group B), i.e., patients with hypertension, diabetes mellitus, cigarette smokers, and obese patients, shows significantly higher values of mean triglyceride than in the normal subjects (P < 0.001). The HDL cholesterol and percent HDL cholesterol values are significantly lower in the high risk patients than in the normal subjects (P < 0.001). A study of the lipid profile of 15 Nigerian patients with coronary heart disease (CHD) (Group C) shows significantly lower in the high-risk patients than in the percent HDL cholesterol than normal subjects (P < 0.001). These values were also found to be significantly lower in Group C patients than in Group B patients (P < 0.01). A compaison of the lipid profile of normal Nigerian subject with those of black Americans shows that the total cholesterol values of normal black Americans are significantly higher than those of normal Nigerians of comparable age and sex (P < 0.001). Although there is no significant difference in the HDL cholesterol values of both black American and Nigerian males and females, the values of the percent HDL cholesterol of black Americans are significnatly lower (P < 0.01) than those of Nigerians of comparable age and sex. This study shows that the values of HDL cholesterol and percent HDL cholesterol of normal African subjects are within the "below average risk" range: the values for Group B subjects (high-risk patients) fall within the "average-risk" range and the values for Nigerian patients with CHD fall within the "high-risk range." Therefore, it appears that the "protective levels" of HDL cholesterol and percent HDL cholesterol are probably the same for all age groups irrespective of race, environment, or socioeconomic factors. These findings also suggest that the difference in the lipid profile between Africans and black Americans may be due to dietary habits rather than to genetic or sociopsychological factors. This explains the presently reported low incidence of atherosclerosis and CHD in Africans. More population-based studies and demographic data are needed to clarify the rhetoric about CHD in Africans.