Background: Fetuin-A has been associated with insulin resistance and inversely related with vascular calcification. The present study evaluated whether serum fetuin-A explains the ethnic disparity in the subclinical atherosclerosis and risk for diabetes between healthy Hispanic and non-Hispanic white (NHW) subjects.
Methods: Fetuin-A was measured in serum of 76 age-matched healthy males (41 NHW, 35 Hispanics). Body mass index, blood pressure, serum lipoprotein cholesterol and triglyceride levels, coronary artery calcium (CAC), fasting glucose and insulin concentrations, and plasma glucose levels 2 h after a 75-g oral glucose tolerance test were measured in all participants. Insulin resistance was estimated using the homeostasis model assessment (HOMA).
Results: Fasting insulin, fasting and 2-h serum glucose, and HOMA values were all significantly higher in Hispanics (p < 0.05 for all), yet CAC trended lower and the prevalence of very high CAC (>400 Agatston score) was lower (P = 0.03). There was no statistically significant difference in serum fetuin-A when comparing Hispanics and NHW (P = 0.12). Furthermore, there was no correlation between fetuin-A levels and CAC (P = 0.9).
Conclusions: Serum fetuin-A concentration was not associated with measures of insulin resistance or with preclinical atherosclerosis in Hispanics and NHW. These data indicate that the disparity in prevalence of insulin resistance, type 2 diabetes, and subclinical atherosclerosis between Hispanics and NHW does not appear attributable to differences in fetuin-A concentrations.