Plasma adiponectin as an index of insulin resistance in gestational diabetes mellitus

Abstract EN

Adiponectin is an adipocyte-derived hormone with profound insulin sensitizing, anti-inflammatory and anti-atherogenic effects.

Hypoadiponectinaemia is known to be associated with insulin resistance, diabetes and obesity.

Gestational diabetes mellitus (GDM) identifies a population of young women at high risk of developing type 2 diabetes. Objectives: In this study we investigated the relationship between adiponectin level and glucose tolerance during pregnancy. Material and Methods: This study included 90 pregnant women between 24th – 28th weeks of gestation.

They were divided into 3 groups according to the results of 100 g oral glucose tolerance test (OGTT).

Group I (n=30) pregnant women with GDM, group II (n=30) pregnant women with impaired glucose tolerance (IGT) and group III (The Control group, n=30) pregnant women with normal glucose tolerance (NGT).

Gestational age was calculated from the date of the last menstrual period and supported by ultrasonography.

All groups were subjected to full history taking, thorough clinical examination, anthropomtric measures, in addition to fasting insulin level, homeostatic model assessment of insulin resistance (HOMA-IR), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and plasma adiponectin level. Results: The results of the present study showed that adiponectin levels were significantly decreased in the group of patients (Group I & II) when compared to the control group (group III) (P<0.001).

Our results showed that pregnant women with GDM (Group I) had a significantly higher fasting insulin (P<0.001), HOMA-IR (P<0.001) and TNF-α (P<0.001) when compared to NGT group (Group III).

While pregnant women with IGT (Group II) were found to have a significantly higher fasting insulin levels (P<0.05), a significant elevation in TNF-α (P<0.05) and non significant elevation of HOMA-IR (P>0.05) when compared to NGT pregnant women.

However, IL-6 levels showed insignificant differences between the three groups (P>0.05).

Our results showed that there was a strong negative correlation between plasma adiponectin level in the group of patients (Group I & II) and fasting insulin level, HOMA-IR and TNF-α (r= -0.73, -0.69 and -0.56, P<0.001, <0.001 and <0.05 respectively), while we could not find a significant correlation between plasma adiponectin and IL-6 (r = 0.23, P>0.05).

Our results also revealed a significant negative correlation between adiponectin level in all patients (Group I & II) and BMI, degree of weight gain during pregnancy and parity (r = -0.57, -0.44, -0.41, P<0.001, <0.05, <0.05 respectively). Conclusion: The results of this study showed a significant decrease in adiponectin level in pregnant women with GDM and IGT.

This may point at its role in the pathogenesis of GDM and its use as an index of insulin resistance and increased risk for future development of type 2 diabetes.