A healthy lifestyle helps to prevent gestational diabetes in those at highest genetic risk

Gestational diabetes is the most common health-related challenge during pregnancy. Today, it is diagnosed in every fifth expectant mother in Finland. Gestational diabetes has a significant impact on the health of both the mother and the child, both during pregnancy and after delivery.

A study conducted at the University of Helsinki investigated the effects of lifestyle intervention on the prevention of gestational diabetes in women at high risk of developing gestational diabetes. In the Finnish Gestational Diabetes Prevention Study (RADIEL), the study subjects received intensified physical exercise and dietary counselling during pregnancy and for the first year following delivery.

In this study, a polygenic risk score (PRS) describing the genetic risk of diabetes was calculated using gene variants known to increase the risk of type 2 diabetes. The risk score for type 2 diabetes was associated with elevated glucose levels in mid- and late pregnancy as well as one year after delivery.

“Gestational diabetes as well as prediabetes and diabetes one year after delivery were also more common among those with higher scores,” says Emilia Huvinen, specialist in obstetrics and gynaecology.

Targeted measures produce better results

The study discovered that genetic risk also affected the link between lifestyle counselling and gestational diabetes as well as diabetes.

“Based on our research, intensified lifestyle interventions benefitted only women at highest genetic risk of developing type 2 diabetes,” Huvinen confirms.

According to her, the results are significant and even globally unique.

“Our study offers one possible explanation for the contradictory results of previous studies investigating the prevention of gestational diabetes till now ,” Huvinen explains.

According to the researchers, genetic-risk scoring would make it possible to identify the expectant mothers most at risk as well as to direct resources and the most effective preventive measures specifically at them. This would be of great importance in terms of both limited societal resources and the health of these mothers and their children.

“At the same time, it’s important to realise that, in the case of diabetes, our genetic background does not determine our future. With the help of a healthy lifestyle, you can reverse the effect of a high genetic diabetes risk,” Huvinen says, offering encouragement.

How the study was conducted

• The Finnish Gestational Diabetes Prevention Study (RADIEL) was conducted in the period 2008–2013 in Helsinki and Lappeenranta.
• Invited to the intervention study were women with a high risk of diabetes planning pregnancy or already in early pregnancy who were obese (BMI > 30 kg/m²) or who had a history of gestational diabetes.
• A total of 724 women were randomised to a control group or to undergo intensified physical exercise and dietary interventions three times during pregnancy and three times in the first year after delivery.
• The dietary advice adhered to Nordic dietary guidelines, while a total of 150 minutes of moderately intensive physical activity was recommended per week.
• A polygenic risk score (PRS) for the genetic risk of diabetes was calculated using 50 known risk variants associated with type 2 diabetes.