HOMA-IR

HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) is a fasting blood index calculated as (fasting insulin in µU/mL × fasting glucose) / k, where k = 22.5 if glucose is in mmol/L (SI units) or k = 405 if glucose is in mg/dL (US conventional units). It estimates whole-body insulin resistance from fasting measures, predominantly reflecting hepatic insulin action, as a low-cost surrogate for clamp methods. Cutoffs are population- and assay-dependent, with no universal threshold; values are commonly cited around 2 to 2.9 in adults.