COMMENTS AND RESPONSES Plasma Retinol- Binding Protein-4 Concentrations Are Elevated in Human Subjects With Impaired Glucose Tolerance and Type

Response to Gavi et al. G avi et al. (1) investigated the associ-ation between visceral adipose tis-sue (VAT) mass by computed tomography and circulating retinol-binding protein-4 (RBP4) concentrations in nondiabetic subjects. They could not find a correlation between VAT and se-rum RBP4 concentrations, while VATwas inversely correlated with serum adi-ponectin concentrations in their subjects. The study by Gavi et al. did not support specific association between circulating RBP4 concentrations and abdominal obe-sity, which we (2) and Graham et al. (3) observed in previous studies. However, it is in accordance with the observation b