Figure 4

Linear regression between the changes of IGF bioactivity and IGFBP-1 level. 0–3 hours (a) and 6–9 hours (b). The symbols represent patients with insulin aspart (black circles), BIAsp70 (open circles), BIAsp 50 (black triangles) and human insulin (open triangles). For all four insulin preparations a significant inverse correlation with IGFBP-1 was observed, being r = - 0.30 for insulin aspart, r = - 0.47 for BIAsp70, r = - 0.40 for BIAsp50, and r = - 0.52 for human insulin group during 0–3 hours (a), while r = - 0.83 for insulin aspart, r = - 0.57 for BIAsp70, r = - 0.40 for BIAsp50, and r = - 0.58 for human insulin group during 6–9 hours (b); all p-values <0.05. For clarity the reference line illustrates the trend of data in four insulin groups.