Stimulated postprandial insulin

Method

Plasma insulin by immunoassay during serial sampling after an intragastric amino-acid preload followed by a fixed mixed-nutrient drink, reported as the maximum concentration reached or as the integrated concentration-time response across the sampling window.

The method is part of the endpoint identity. Studies measuring the same quantity by a different method are held as separate endpoints.

Notes

SIGN INVERSION HAZARD against fasting insulin. A HIGHER nutrient-stimulated insulin response is the benefit here -- it means an intact beta-cell response to a load -- while a HIGHER fasting insulin is the harm, because it indexes insulin resistance. The same analyte name in two physiological states with opposite benefit directions; confirm the sampling state before creating an edge. Also distinct from C-peptide, co-secreted but not subject to hepatic first-pass extraction and therefore the better index of pancreatic secretion, and from HOMA-IR, a fasting-state derived index.