Relationship of raised serum total and protein bound sialic acid levels with hyperinsulinemia and indices of insulin sensitivity and insulin resistance in non-diabetic normotensive obese subjects

Abstract

AimsObesity is known to be associated with cardiovascular disease and interaction between inflammation and insulin resistance is reported to enhance the cardiovascular risk in these subjects. The present study was designed to assess indices of insulin sensitivity, insulin resistance and sialic acid levels and their association in non-diabetic normotensives obese subjects. Materials and methodsThe present study was conducted in 30 obese male subjects and results were compared with 30 subjects with normal body weight. Insulin, total sialic acid and protein bound sialic acid were estimated in all the subjects. Insulin resistance was calculated by using Homeostatic Model Assessment-insulin resistance formula. Insulin sensitivity was assessed by quantitative insulin check index and insulin sensitivity index. ResultsInsulin resistance, serum total and protein bound sialic acid levels were significantly increased in obese cases as compared to non-obese controls. Total sialic acid showed significant positive correlation with HOMA-IR (p<0.01), BMI (p<0.01), waist and hip circumference (p<0.01) and negative correlation with QUICKI (p<0.01) and insulin sensitivity index (p=0.018). There was no significant correlation between protein bound sialic acid and indices of insulin resistance and insulin sensitivity. ConclusionSialic acid levels are elevated in obese subjects and its association with insulin resistance and reduced insulin sensitivity may enhance the cardiovascular risk in these subjects.