Study of Serum Adiponectin and Interleukin-1β Levels in Women with Gestational Diabetes

Pregnancy is associated with alterations in the regulation of glucose metabolism caused by actions of various placental hormones and substances that antagonise the action of insulin leading to a state of relative insulin resistance as pregnancy progresses. Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. Adiponectin is known to be synthesised by adipocytes as well as by the placenta during pregnancy. It has an insulin-sensitising and anti-atherosclerotic actions. Interleukin-1β (IL-1β) is a member of interleukin-1 cytokine family and is known to involve in immune-mediated disease and regulation of inflammation. Accumulating evidence indicates that diseases related to metabolic syndrome are characterised by abnormal cytokine production, including IL-1β.

To evaluate serum adiponectin and IL-1β levels in women with GDM and correlate their levels with blood glucose level.

A hospital-based case-control study was conducted in which 30 cases of GDM along with age-matched normal glucose tolerance (NGT) pregnant controls were taken. Informed consent was taken and subjects were screened at 24-28^th weeks of gestation for GDM by glucose challenge test (GCT), followed by oral glucose tolerance test. Socio-demographic data and clinical evaluation were done using a pre-structured perfoma. Serum concentration of adiponectin and IL-1β was measured using enzyme-linked immunosorbent assay.

The mean value of serum adiponectin level was significantly lower, 5.76 μg/ml SD ± 2.01351 in cases of GDM compared to NGT controls (14.12 μg/dl SD ± 4.99734), P < 0.05. A cutoff value of serum adiponectin level ≤8.7 μg/ml gave a sensitivity and specificity of 100% when used alone for identifying cases of GDM in the present study. Serum level of IL-1β was less than the detectable level (<6.5 pg/ml) in NGT controls. In this study, 26.7% of GDM cases showed levels >6.5 pg/ml (median 18.2 [12.8-34.62]), rest of the cases (73.3%) had levels less than 6.5 pg/ml. A significant inverse correlation was seen between serum adiponectin and HbA1c, pre-gestational BMI, and blood glucose level at GCT. There was no significant correlation of serum IL-1β level with any of the parameters.

GDM is associated with low level of serum adiponectin, and serum adiponectin may be used as a biomarker for detecting cases of GDM to complement blood glucose level.