Post-GDM hormone responses differ between South Asian and Nordic women

Researchers analysed oral glucose tolerance test data from 178 South Asian and 107 Nordic women with previous gestational diabetes mellitus (GDM), recruited in the Oslo region. Participants were assessed a median of 16.5 months after giving birth and stratified by glycaemic status. The analysis measured glucagon, glucose-dependent insulinotropic polypeptide (GIP) and GLP-1 responses; pre-hepatic insulin levels were estimated from C-peptide kinetics.

Among women with normal glucose tolerance, early glucagon suppression during the first 15 minutes after glucose intake was less pronounced in South Asian than Nordic women (p=0.002), and total glucagon exposure was higher (p=0.013). Fasting glucagon did not differ, nor did GIP or GLP-1 responses. In women with prediabetes or diabetes, South Asian women had higher fasting glucagon (p=0.010) and lower GIP responses (p<0.001); GLP-1 responses did not differ. Higher pre-hepatic insulin levels in normoglycaemic South Asian women were associated with lower insulin sensitivity (p<0.001), not differences in incretin levels.

The findings describe differences in hormone responses after GDM, but do not establish their causes or show that they predict later diabetes. The authors note that the cohort was not population-based, limiting generalisability beyond similar hospital-recruited women with previous GDM. The study does not test a clinical intervention or support changes to care.