Findings highlight an important public health opportunity to prevent type 2 diabetes in a high-risk population
Women with a history of diabetes during pregnancy can still reduce their chances of developing type 2 diabetes by adopting a healthy lifestyle, such as eating healthy, quitting smoking, exercising regularly and not being overweight, according to a study published in The BMJ .
The results show that women who adhered to five key lifestyle factors (healthy weight, high-quality diet, regular physical activity, moderate alcohol consumption and not smoking) had a 90% lower risk of developing the disorder in compared to women who did not adhere to any of them, including among those who were overweight or obese, or had a higher genetic risk of type 2 diabetes.
It is widely known that a healthy lifestyle is associated with a lower risk of developing type 2 diabetes in generally healthy middle-aged populations.
But less is known about whether this also applies to high-risk women with a history of diabetes in pregnancy (gestational diabetes), and whether obesity status or genetic risk for type 2 diabetes influences this association.
To fill these research gaps, the researchers evaluated the associations of adherence to optimal levels of five modifiable risk factors: healthy body mass index, high-quality diet, regular physical activity, moderate alcohol consumption, and non-smoking, with the risk of developing type 2 diabetes among these high-risk women.
Their findings are based on data from 4,275 women with a history of gestational diabetes mellitus from the Nurses’ Health Study II with repeated measurements of weight and lifestyle factors over 28 years of follow-up.
The researchers also assessed whether these associations changed by obesity status or underlying genetic susceptibility to type 2 diabetes. Over an average of 28 years of follow-up, 924 women developed type 2 diabetes.
After taking into account other important diabetes risk factors, the researchers found that participants who had optimal levels of all five modifiable factors after the index pregnancy had a 90% lower risk of developing type 2 diabetes compared to those who did not have none.
Each additional optimal modifiable factor was associated with a decreasing risk of type 2 diabetes. For example, women with one, two, three, four, and five optimal levels of modifiable factors compared to none had a 6%, 39% risk. , 68%, 85% and 92% lower, respectively.
And these beneficial associations were consistently observed, even among women who were overweight or obese or who had a higher genetic susceptibility to type 2 diabetes.
This is an observational study , so it cannot establish cause, and the researchers acknowledge that the data was based on self-report, which may have affected accuracy. Additionally, the study predominantly included health professionals of European descent, so the results may not apply to people from other racial or ethnic groups or socioeconomic groups.
However, strengths include using data from a large study with repeated measurements of behavioral and health-related risk factors, which helps better capture long-term lifestyle habits and reduce measurement error and misclassification.
As such, the researchers say their study "highlights the important public health opportunity for the prevention of type 2 diabetes in this high-risk population."
