Effect of gestational diabetes and hypertensive disorders of pregnancy on postpartum cardiometabolic risk

AIMS The cumulative effect of gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP) on postpartum cardio-metabolic diseases is equivocal. We aimed to assess the associations of GDM and HDP's individual and synergic contribution to risks of postpartum cardio-metabolic diseases (metabolic syndrome (MetS), abnormal glucose metabolism and hypertension (HTN)). METHODS Of participants from a Singapore birth cohort, 276 mothers attending the 5-year postpartum visit were included in this study. During this visit, we collected mothers' history of GDM and HDP in all live births in a chronicle sequence and assessed the cardio-metabolic risks based on blood pressure, anthropometry and a panel of serum biomarkers. We diagnosed MetS, abnormal glucose metabolism and HTN according to Adult Treatment Panel III 2000 and World Health Organization guidelines. RESULTS Of 276 mothers, 157 (56.9%) had histories of GDM while 23 (8.3%) had histories of HDP. After full adjustment, we found associations of GDM episodes with postpartum abnormal glucose metabolism (single episode: relative risk (RR) 2.9 (95% CI: 1.7, 4.8); recurrent episodes (≥2): RR = 3.8 (2.1-6.8)). Also, we found association between histories of HDP and HTN (RR = 3.6 (1.5, 8.6)). Having either (RR 2.6 (1.7-3.9)) or both gestational complications (RR 2.7 (1.6-4.9)) was associated with similar risk of postpartum cardio-metabolic disease. CONCLUSIONS Mothers with GDM or HDP had a threefold increased risk of postpartum abnormal glucose metabolism or HTN, respectively. Having both GDM and HDP during past pregnancies was not associated with additional risk of postpartum cardio-metabolic diseases beyond that associated with either complication alone.