Aims: People of South Asian descent face an increased risk of Type 2 diabetes mellitus (DM) and coronary artery disease (CAD) compared with other ethnic groups. One candidate factor underlying this risk may be adiponectin, as circulating levels of this adipocyte-derived protein are reduced in both Type 2 DM and CAD. In a recent study, we assessed the relationship between adiponectin and gestational diabetes (GDM), a potential model of early events in the natural history of Type 2 DM. Here, we report the impact of ethnicity on plasma adiponectin concentration in that study.
Methods: A cross-sectional study was performed in 180 women undergoing oral glucose tolerance testing in late second or early third trimester to investigate the relationship between adiponectin and glucose tolerance in pregnancy. Based on self-reported ethnicity, participants were stratified into three groups: (i) Caucasian (n = 116), (ii) South Asian (n = 31), and (iii) Asian (n = 28).
Results: Median adiponectin concentration was much lower in the South Asian group (9.7 micro g/ml) than in Caucasians (15.8 micro g/ml) or Asians (16.1 micro g/ml) (overall P < 0.0001). With adjustment for age, prepregnancy body mass index, weight gain in pregnancy, previous history of GDM, family history of DM, fasting insulin and glucose intolerance, mean adiponectin remained significantly lower among South Asians compared with either Caucasians (P < 0.0001) or Asians (P = 0.0034).
Conclusions: Women of South Asian descent exhibit significantly reduced plasma concentrations of adiponectin in pregnancy compared with Caucasian and Asian counterparts. This observation raises the possibility of hypoadiponectinaemia as a potential factor contributing to the increased risk of diabetes and cardiovascular disease in South Asians.