IGF-1 and growth. Insulin-like growth factor-1 (IGF-1) increases during follow-up (A). Enrollment IGF-1 had negative correlations with several inflammatory markers (B, color indicates statistical significance level, + or - indicates a positive or negative correlation). This effect reduced between IGF-1 and concurrent inflammatory markers at later time points. Concentrations of IGF-1 and endotoxin correlated positively and negatively (respectively) with linear growth over the course of the study (C).