Obesity affects blacks, whites differently in prediabetes
Modestly severe obesity has differential effects on the pathogenic mechanisms underlying glucose homeostasis and atherogenesis in Americans of white and black ethnicities with prediabetes, according to research published in Diabetes Care.
“We conclude that the regulation of glucose homeostasis and lipid/lipoprotein metabolism appears to differ in modestly severely obese African Americans and white Americans with prediabetes,” the researchers wrote.
Sara J. Healy, MD, of the Wexner Medical Center, The Ohio State University, and colleagues assessed 145 adults with prediabetes (mean age, 46.5 ± 11.2 years; mean BMI, 37.8 ± 6.3 kg/m2), including 61 whites and 84 blacks.
The investigators measured fasting levels of lipids, lipoproteins, inflammatory marker C-reactive protein (CRP), HDL functionality, oxidized LDL, adiponectin and interleukin-6; serum levels of glucose, insulin and C-peptide were measure during an oral glucose tolerance test.
The researchers obtained values for insulin sensitivity index, glucose effectiveness index, glucose effectiveness at zero insulin (GEZI) and acute insulin response to glucose (AIRg) through a frequently sampled IV glucose tolerance test, using MINMOD software.
Mean levels of fasting and incremental serum glucose, insulin and C-peptide were generally higher in whites than blacks. Mean Si did not differ in whites compared with blacks (2.6 ± 2.3 vs. 2.9 ± 3 x 10-4 x min-1 [µU/mL]-1)
Mean values for AIRg and disposition index, along with glucose effectiveness index and GEZI, were lower in whites than blacks. Higher serum triglyceride levels were also observed in whites vs. blacks (116.1 ± 55.5 mg/dL vs. 82.7 ± 44.2 mg/dL; P = .0002).
No significant differences were demonstrated between whites and blacks for mean levels of apolipoprotein A-I, HDL cholesterol, paraoxonase 1, oxidized LDL, CRP, adiponectin and IL-6.
“Longitudinal studies of underlying putative mechanisms and molecular targets for glucose homeostasis, lipid/lipoprotein metabolism, and HDL functionality in a large sample of obese African Americans and white Americans are warranted,” the researchers wrote.
Disclosure: The researchers report no relevant financial disclosures.