RBP4 and type 2 diabetes mellitus: In agreement with our null finding in the total population, a 9-year prospective cohort study among 1090 African American and Caucasian men and women in the US, with 543 incident cases of type 2 diabetes, has also reported a HR of 1.09 (95% CI 0.66–1.79) when comparing the extreme tertiles of RBP4 concentration [16].