Previous studies identify gestational diabetes (GD) as a risk factor for intermediate markers of cardiovascular disease (CVD) risk; however, few are prospective, evaluate hard CVD end points, or account for shared risk factors, including body weight and lifestyle. The Nurses’ Health Study II (NHS II) is an observational cohort study of US female nurses. 89,479 women were included who reported at least one pregnancy and were free of CVD and cancer at baseline. Follow-up through May 31, 2015 was complete for more than 90% of eligible participants. In this study, to prospectively evaluate history of GD in relation to incident CVD risk with follow-up of nearly 90,000 US women older than 26 years, women with a history of gestational diabetes had 43% greater risk of CVD (myocardial infarction or stroke) compared with women without prior gestational diabetes, although absolute rates in this cohort were low. Adhering to healthy lifestyle factors over follow-up mitigated this modestly elevated risk.  Participants had a mean age of 34.9 (4.7) years. Adjusting for age, prepregnancy body mass index, and other covariates, GD vs no GD was associated with subsequent CVD. Additional adjustment for weight gain since pregnancy and updated lifestyle factors attenuated the association. Classifying GD by progression to T2D in relation to CVD risk indicated a positive association for GD with progression to T2D vs no GD or T2D, and an attenuated relationship for GD only. Gestational diabetes was positively associated with CVD later in life, although the absolute rate of CVD in this younger cohort of predominantly white women was low. This relationship is possibly mediated in part by subsequent weight gain and lack of healthy lifestyle. 1,161 incident self-reported nonfatal or fatal myocardial infarction or stroke, confirmed via medical records.

JAMA Intern Med; 2017 Oct 16; EPub Ahead of Print; DK Tobias, JJ Stuart, S Li, et al