Evaluation of the effect of serum-free fatty acids on the onset of insulin resistance in healthy obese adults

Abstract

Objectives: Although it is unclear which free-fatty acids (FFA) is more closely associated with insulin resistance (IR), increased FFA levels of are closely related to IR in obese individuals. The aim of this study was to determine the FFA profile in serum of individuals with various body mass indices (BMIs) that most accurately predicted the onset of IR in obese people. Methods: In the current study, a cross-sectional design was used, and 120 participants were separated into four subgroups based on their BMIs, with ages (25–55) years that were matched between the subgroups. Demographic, anthropometric were taken. Measured biochemical parameters were glycated hemoglobin (HbA1c), free fatty acids (FFA), lipid profile, and homeostasis model assessment of insulin resistance (HOMA-IR). Results: The current study found that all variables significantly increased with increasing BMI as compared to the normal weight group (non-obese). Compared to WHR, WC had a stronger association with increased FFA (r=0.314, p=0.001) than did WHR (r=0.183, p=0.000). A positive significant association of FFA with total cholesterol (TC) and very low-density lipoprotein cholesterol (VLDL-C) as well as a positive significant correlation with insulin resistance, represented by HOMA-IR (r= 0.464, p=0.011). Finally, FFA was identified as an independent risk factor for insulin resistance with significant predictive power (under area curve 0.963). In conclusion, the present study demonstrated that obesity, defined by WC was the strongest indicator for increasing FFA than WHR, as well as revealed a strong positive association with IR (represented by HOMA-IR), which may be a significant risk factor for obesity-induced insulin resistance through FFA.