Incidence of Heart Failure Related to Co-Occurrence of Gestational Hypertensive Disorders and Gestational Diabetes

BACKGROUND: The extent to which their co-occurrence of gestational hypertensive disorders (GHTD) and gestational diabetes mellitus (GDM) influences heart failure (HF) risk is unclear. OBJECTIVES: The purpose of this study was to characterize the risk of HF related to concomitant GHTD and GDM. METHODS: We conducted a population-based cohort study using the Ministry of Health and Long-Term Care of Ontario (Canada) health care administrative databases. We included women with a livebirth singleton delivery between July 1, 2007, and March 31, 2018, and excluded those with prepregnancy diabetes, hypertension, HF, or coronary artery disease. GDM, GHTD, peripartum cardiomyopathy (at index pregnancy) were identified using diagnosis coding. Incident HF was assessed from index pregnancy until March 31, 2020. We estimated associations of GDM and/or GHTD with peripartum cardiomyopathy and incident HF. RESULTS: Among 885,873 women (mean age: 30 years, 54,015 with isolated GDM, 43,750 with isolated GHTD, 4,960 with GDM and GHTD), there were 489 HF events over 8 years. Compared to no-GDM and no-GHTD, isolated GDM (adjusted hazard ratio [aHR]: 1.44; 95% CI: 1.02-2.04) and isolated GHTD (aHR: 1.65; 95% CI: 1.17-2.31) were associated with a higher risk of incident HF. The co-occurrence of GDM and GHTD was associated with a higher HF risk (aHR: 2.64; 95% CI: 1.24-5.61). GDM and GHTD increased the risk of peripartum cardiomyopathy (adjusted risk ratio [aRR]: 7.30; 95% CI: 6.92-7.58), similarly to isolated GHTD (aRR: 7.40; 95% CI: 7.23-7.58). CONCLUSIONS: The co-occurrence of GDM and GHTD was associated with a significantly high risk of incident HF.