Sex Differences in Insulin Resistance and Triglyceride/HDL-Cholesterol Ratio in Human Subjects

Background: Insulin resistance (IR) plays a major role in dyslipidemia and the associated cardiovascular disease risk. To date, it remains unclear as to how IR alters plasma lipid profile in males versus females. The present study is an initial step to determine sex-specific differences in IR and plasma lipid profile using 40 μL of capillary blood. Methods: 12 adults aged 30-64 were recruited from Rowan Medicine-Sewell clinics, with 7 participants (3 males, 4 females) consenting to the study. After collecting 40 μL of capillary blood via finger prick, the samples were analyzed for glucose, triglyceride (TG), and HDL-cholesterol (HDL-C) using Abbott Cholestech LDX analyzer. Height, weight, BMI, waist circumference, and blood pressure were recorded. As a surrogate marker for IR, TG-fasting glucose (TyG) index was calculated [Ln[TG (mg/dL) x FPG (mg/dL)]/2]. To assess altered lipid profile, TG/HDL-C ratio was calculated. Results: Two male and two female participants fasted for this study. Both male subjects exhibited elevated TyG indices, TG levels, and TG/HDL-C ratios. Among females, one subject showed a high TyG index along with elevated TG and TG/HDL-C ratio, while the other subject had a low TyG index and TG, but with an elevated TG/HDL-C ratio due to low HDL-C. Conclusion: The small sample size in this study is insufficient for data analysis and interpretation. However, if similar trends—such as higher TyG indices, TG levels, and TG/HDL-C ratios in males—are observed in a larger cohort, it may suggest a more pronounced role of IR in exacerbating dyslipidemia among males compared with age-matched females.