5 Modifiable Factors in Women with History of Gestational Diabetes Mellitus That Can Reduce the Risk of T2D

Among women with a history of gestational diabetes mellitus, modifying 5 different lifestyle risk factors was associated with a lower risk of type 2 diabetes (T2D), according to the results of a study published in The BMJ.

Investigators found that these results were seen even among individuals who were overweight, had obesity, or who have a greater genetic susceptibility.

Investigators included 4275 individuals with a history of gestational diabetes mellitus and respectively measured weight and lifestyle factors between 1991 and 2009. The data were self-reported, and the individuals were clinically diagnosed with T2D.

The 5 modifiable risk factors included not being overweight or having obesity with a body mass index of less than 25; a high-quality diet, which was calculated in the top two-fifths of the modified Alternate Healthy Eating Index; regular exercise of 150 minutes or more of moderate intensity or 75 minutes or more of vigorous intensity; moderate alcohol consumption, which was defined as 5 to 14.9 g/day; and currently not smoking.

After a median follow-up of 27.9 years, 924 of the 4275 women developed T2D. Individuals who had optimal levels of 5 factors had more than a 90% lower risk of developing T2D compared to individuals who did not have any optimal levels for of the risk factors for the disorder.

The hazard ratios of T2D for those with 1, 2, 3, 4, and 5 modifiable factors compared with 0 were 0.94, 0.61, 0.32, 0.15, and 0.08, respectively.

Among individuals with a body mass index of 25 or greater, the hazard ratio for achieving optimal levels of all other 4 risk factors was 0.40. Additionally, for women with higher genetic susceptibility, the hazard ratio of developing T2D for having 4 factors was 0.11, whereas in the group with all 5 factors there were no T2D events observed.

The genetic susceptibility for T2D was assessed by a genetic risk score based on 59 single nucleotide polymorphisms that were associated with T2D.

At baseline, investigators said that women who had optimal levels of 4 or more modifiable factors were more likely to be older at their first birth, have longer breastfeeding duration, were pre-menopausal, and were less likely to have a family history of diabetes.

Investigators said that limitations of the study included the self-reported modified risk factors as well as self-reported weight and lifestyle habits. They also said that the population consisted of mainly health care professionals of European ancestry, which could limit the application of these findings across other racial, ethnic, and socioeconomic groups.

They also noted that women who were aware of their risk for T2D and modified their risk factors may have also been more likely to get screened for T2D, therefore, the results could have underestimated the benefit associated with the modifiable factors in the study.

Reference

Yang J, Qian F, Chavarro J E, Ley S H, Tobias D K, Yeung E et al. Modifiable risk factors and long term risk of type 2 diabetes among individuals with a history of gestational diabetes mellitus: prospective cohort study. BMJ. 2022;378 :e070312 doi:10.1136/bmj-2022-070312