New blood test for gestational diabetes may improve early screening of women at risk

Researchers from Brigham and Women’s Hospital, in Bosto, have come up with a new simple blood test for the early screening of gestational diabetes in women at increased risk.
These findings are from a new study, published in the journal Diabetes Care, that has huge consequences for assessing gestational diabetes risk in a more systematic, repeatable and accurate manner.
GDM commonly develops in the second half of pregnancy, but is often only detected in the beginning of the third trimester, as accurate early diagnostic tools were until now lacking.
An early and rapid diagnosis of GDM is desirable to reduce adverse pregnancy outcomes for both mother and child. These include abnormal fetal growth, pre-term birth, pre-eclampsia and fetal injury.
The standard of care in GDM screening here in the UK is a series of questions submitted to women in the first weeks of pregnancy to determine if they have one or more risk factors for GDM, which may or may not call for oral glucose tolerance testing (OGTT).
In their new research, the American researchers propose that traditional risk assessment methods, such as early OGTT screening, should be combined with the measurement of a promising new biomarker in the blood known as GCD59.
This is based on earlier research conducted by scientists at Harvard Medical School who found that the glycated protein CD59 is significantly elevated in people with diabetes. This compound can be detected in the blood as early as the 24th week of pregnancy.
In order to test the accuracy of GCD59 in predicting risks, the team conducted a case-control study involving 1,000 pregnant women – 500 of whom showed signs of impaired glucose tolerance through early OGTT testing.
Researchers found that, when compared with the control participants (who had had a normal glucose tolerance test), the group of 127 women diagnosed with GDM during the study had a 10-fold higher blood level of GCD59.
In addition to that, elevated GCD59 levels appeared to correlate with a higher incidence of large-for-gestational-age newborns in a linear way, meaning that the higher the levels, the higher was the risk for complications to arise in the offspring.
Out of the 58 large-for-gestational-age babies born to mothers that failed the glucose tolerance test in this study, 80 percent were born to mothers who had GCD59 levels seven-fold higher than control women.
The manifest diagnostic power of GCD59 could have a major impact on future screening approaches for GDM in earliest stages of pregnancy.