Comparison of the mean circulating levels between T1D patients with complications and controls revealed greater changes in IGFBP-2 (3–6-fold), IGFBP-1 (1.5–2.5-fold), and IGFBP-6 (1.5–2.5-fold) in both discovery and confirmation sample sets, whereas the levels of IGFBP-3 were moderately but significantly reduced (~0.8-fold). Here, IGFBP1 is linked to type 1 diabetes mellitus.