Fructosamine and Triglycerides - Developing an Index for Assessing Insulin Resistance

Abstract

Introduction: Insulin resistance (IR) is a metabolic condition where cells become less responsive to insulin, affecting glucose absorption and leading to diseases like type 2 diabetes. Factors like obesity and high triglycerides worsen IR. Fructosamine is a key marker for short-term glycemic control and can indicate IR. Various methods, like the euglycemic clamp and HOMA-IR index, assess IR, with the TyG index emerging as a simple and reliable tool due to its strong correlation with IR. Objective: To develop and evaluate a novel IR index that incorporates both fructosamine and triglyceride levels, aiming to improve the accuracy of IR assessment compared to existing methods. Methods: This study investigated IR using established methods and proposed a novel TrigFruc index incorporating fructosamine. Data from 200 individuals was analyzed to assess the TrigFruc index's performance compared to existing methods (HOMA-IR and TyG index). Descriptive statistics summarized participant demographics, and Pearson's correlation evaluated the relationship between TrigFruc and HOMA-IR and between TrigFruc and TyG index. A receiver operating characteristic (ROC) analysis identified the optimal TrigFruc cut-off point for IR detection, comparing its sensitivity and specificity to HOMA-IR and TyG index. Results: Study with 200 participants (63% female, avg. age 46.6 years), the established HOMA-IR index identified IR in 32% (64 individuals) while the TyG index found it in 66% (132). The new TrigFruc index showed a weaker correlation with HOMA-IR (r=0.28) compared to the TyG index (r=0.44). For detecting IR based on HOMA-IR, the optimal TrigFruc cut-off (Ln 4.57) had just 50% sensitivity (correctly identifying half of true IR cases) but low specificity (23%, high misclassification of non-IR cases). When compared to the TyG index, the optimal TrigFruc cut-off (Ln 4.74) showed excellent performance with high sensitivity (85%, strong ability to identify true IR) and specificity (95%, low misclassification of non-IR). Conclusion: The TrigFruc index, incorporating fructosamine, shows promise for IR assessment. Compared to HOMA-IR, it exhibits better correlation with the TyG index and superior sensitivity and specificity for IR detection when using the TyG index as a reference. Keyword: Insulin Resistance, TrigFruc Index, Fructosamine, Glycemic Control