Song Y, Søndergaard E, Jensen MD, et al. - Often concordance is observed between Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) and Adipose Insulin Resistance index (ADIPO-IR) values. Researchers conducted this study to investigate if there are groups discordant for HOMA-IR and ADIPOpalmitate-IR and, if so, what are their defining features. They obtained and analyzed the body composition, basal metabolic rate (BMR), fasting plasma lipids, insulin, glucose, and free fatty acid palmitate concentrations data of 466 volunteers from previous research studies. They defined middle 2 population quartiles for HOMA-IR and Adipose Insulin Resistance index palmitate concentration (ADIPO_palmitate-IR) as medium HOMA-IR and ADIPO_palmitate-IR (MH and MA), the top and bottom quartiles as high/low HOMA (HH/LH), and high/low ADIPO_palmitate as HA/LA. Groups discordant for HOMA-IR and ADIPO-IR were identified (HHMA, LHMA, MHHA, and MHLA). The concordant groups had significantly greater body fat and fasting triglycerides (TGs) with higher indices (HHHA > MHMA > LHLA). MHHA and MHLA differed in terms of visceral fat and fasting TGs, whereas HHMA and LHMA differed in terms of BMR. Findings thereby reveal unique features of adults discordant for HOMA-IR and ADIPO-IR including differences in visceral fat, TGs, and BMR. They indicate the presence of different forms of insulin resistance, which should be addressed when studying insulin resistance in the future.