Interactive Calculator to Estimate Insulin Sensitivity (IS) in Type 1 Diabetes

Introduction: Euglycemic hyperinsulinemic clamps, although costly, time- and labor-intensive, are “gold standard” in measuring insulin sensitivity (IS). Several formulae to estimate IS in people with Type 1 diabetes (T1D) exist (DOI: 10.1007/978-3-030-81303-1_18-1), using various routine and research assays, and with wide ranging IS results. Aim: To develop a free online tool to estimate IS using different metrics and existent formulae and compare estimated IS with measured glucose disposal rate (GDR) from 104 clamp studies. Methods: We prepared an online tool for calculating IS using 17 formulae. Suitable formula(e) are suggested based on available (clinical and research) data. We also compare calculated IS with measured IS (GDR) from clamp studies in 104 adults with T1D (mean±SD) age 34±7 yrs, T1D duration 10±4 yrs, HbA1c 7.7±1.5%, 33 with microvascular complications). Logistic regression was used to infer probability of calculated IS being below GDR=4.45 mg/kg/min or above GDR=6.5 mg/kg/min, which represent respectively the median and 75th percentile of measured GDR values. Results: A calculator is available at www.bit.ly/estimated-GDR and an example result in the Figure 1. Estimated IS varied widely, but results interpretation is generally consistent. Conclusion: We developed an interactive tool to estimate IS in T1D for clinical and research use. Disclosure A.S.Januszewski: None. P.Niedzwiecki: None. N.Sachithanandan: None. G.M.Ward: None. D.N.O'neal: None. D.Zozulinska-ziolkiewicz: Advisory Panel; Abbott, Lilly, Lilly, Novo Nordisk, Medtronic, Speaker's Bureau; Abbott, Ascensia Diabetes Care, Novo Nordisk, Medtronic, Boehringer-Ingelheim, AstraZeneca. A.Uruska: Other Relationship; Lilly, Boehringer-Ingelheim, AstraZeneca, Ascensia Diabetes Care, Sanofi. A.Jenkins: Advisory Panel; Insulet Corporation, Board Member; Insulin for Life, Research Support; Abbott Diabetes, Medtronic, Hemsley Charitable Trust, Juvenile Diabetes Research Foundation (JDRF), National Institutes of Health.