AIP and type 2 diabetes mellitus: The main findings of our study are as follows: first, serum FGF19 levels of T2D patients were significantly lower than those in healthy controls; second, arteriosclerosis parameters, including baPWV and AIP, significantly decreased across ascending tertiles of serum FGF19 levels in patients with T2D; and third, after adjusting for other clinical covariates, the serum FGF19 levels were independently and inversely associated with baPWV in patients with T2D.