Long-term cardiovascular outcomes of gestational diabetes mellitus: a prospective UK Biobank study

Background Previous studies showed that gestational diabetes mellitus (GDM) can be a risk factor for subsequent atherosclerotic cardiovascular disease. However, there is a paucity of information regarding diverse cardiovascular outcomes in elderly women after GDM. In the current study, we examined whether women with a history of GDM have an increased risk for long-term overall cardiovascular outcomes. Methods Among the UK participants, we included 219,330 women aged 40 to 69 years who reported at least one live birth. The new incidence of diverse cardiovascular outcomes was compared according to GDM history by multivariable Cox proportional hazard models. In addition, causal mediation analysis was performed to examine the contribution of well-known risk factors to observed risk. Results After enrollment, 13,094 women (6.0%) developed new overall cardiovascular outcomes. Women with GDM history had an increased risk for overall cardiovascular outcomes [adjusted HR (aHR) 1.36 (95% CI 1.18-1.55)], including coronary artery disease [aHR 1.31 (1.08-1.59)], myocardial infarction [aHR 1.65 (1.27-2.15)], ischemic stroke [aHR 1.68 (1.18-2.39)], peripheral artery disease [aHR 1.69 (1.14-2.51)], heart failure [aHR 1.41 (1.06-1.87)], mitral regurgitation [aHR 2.25 (1.51-3.34)], and atrial fibrillation/flutter [aHR 1.47 (1.18-1.84)], after adjustment for age, race, BMI, smoking, early menopause, hysterectomy, prevalent disease, and medication. In mediation analysis, overt diabetes explained 23%, hypertension explained 11%, and dyslipidemia explained 10% of the association between GDM and overall cardiovascular outcome. Conclusions GDM was associated with more diverse cardiovascular outcomes than previously considered, and conventional risk factors such as diabetes, hypertension, and dyslipidemia partially contributed to this relationship.