title: Ethnic differences in lipid metabolism in two groups of obese South African women.
abstract: There is a higher prevalence of ischemic heart disease (IHD) in South African white than black women. The objective of this study was to determine biochemical explanations for this prevalence. The study group contained 15 obese black women (OBW) and 14 obese white women (OWW), all premenopausal, who were examined after an overnight fast. Anthropometric measurements and blood concentrations of glucose, non-esterified fatty acids (NEFAs), catecholamines, plasminogen activator inhibitor-1, C-peptide, proinsulin, lipograms, cortisol, growth hormone, and post-heparin lipoprotein lipase activity were measured during an oral glucose tolerance test (OGTT). Body composition was measured using bioelectrical impedance analysis, and subcutaneous and visceral fat mass were assessed with CT-scans. Visceral fat area was higher in OWW (139.7 +/- 10.7 cm(2)) than in OBW (72.3 +/- 3.9 cm(2)) (P < 0.01), as were fasting and 3 h triglyceride concentrations (P < 0.05 for all). OWW also had higher NEFA levels than OBW at 3 and 4 h compared with OBW (P < 0.05 for both). Fasting cortisol (266 +/- 24 vs. 197 +/- 19 nmol/l; P < 0.05) was higher in OWW than in OBW. These data demonstrate that OWW have higher visceral fat mass than OBW, which may lead to a more atherogenic fasting and postprandial lipid profile. The higher cortisol levels of the OWW may promote visceral fat deposition.
authors.affiliation: Department of Chemical Pathology, Johannesburg General Hospital, Parktown 2193, Johannesburg, South Africa.
authors.forename: C
authors.initials: C
authors.lastname: Punyadeera
authors.forename: M T
authors.initials: MT
authors.lastname: van der Merwe
authors.forename: N J
authors.initials: NJ
authors.lastname: Crowther
authors.forename: M
authors.initials: M
authors.lastname: Toman
authors.forename: G P
authors.initials: GP
authors.lastname: Schlaphoff
authors.forename: I P
authors.initials: IP
authors.lastname: Gray
mesh_terms: D000328:Adult; D019540:Area Under Curve; D044383:Black People; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition; D015992:Body Mass Index; D002096:C-Peptide / Q000097:blood / Q000378:metabolism; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005260:Female; D005951:Glucose Tolerance Test; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007328:Insulin / Q000097:blood; D050356:Lipid Metabolism; D008055:Lipids / Q000097:blood; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000209:etiology*; D009765:Obesity / Q000208:ethnology* / Q000378:metabolism*; D013019:South Africa; D014057:Tomography, X-Ray Computed; D044465:White People
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D008055:Lipids; D019382:Human Growth Hormone; D006854:Hydrocortisone