Adverse Pregnancy Outcomes and Incident Heart Failure in the Women's Health Initiative.

Importance: Some prior evidence suggests that adverse pregnancy outcomes (APOs) may be associated with heart failure (HF). Identifying unique factors associated with the risk of HF and studying HF subtypes are important next steps. Objective: To investigate the association of APOs with incident HF overall and stratified by HF subtype (preserved vs reduced ejection fraction) among postmenopausal women in the Women's Health Initiative (WHI). Design, Setting, and Participants: In 2017, an APO history survey was administered in the WHI study, a large multiethnic cohort of postmenopausal women. The associations of 5 APOs (gestational diabetes, hypertensive disorders of pregnancy [HDP], low birth weight, high birth weight, and preterm delivery) with incident adjudicated HF were analyzed. In this cohort study, the association of each APO with HF was assessed using logistic regression models and with HF subtypes using multinomial regression, adjusting for age, sociodemographic characteristics, smoking, randomization status, reproductive history, and other APOs. Data analysis was performed from January 2020 to September 2021. Exposures: APOs (gestational diabetes, HDP, low birth weight, high birth weight, and preterm delivery). Main Outcomes and Measures: All confirmed cases of women hospitalized with HF and HF subtype were adjudicated by trained physicians using standardized methods. Results: Of 10 292 women (median [IQR] age, 60 [55-64] years), 3185 (31.0%) reported 1 or more APO and 336 (3.3%) had a diagnosis of HF. Women with a history of any APO had a higher prevalence of hypertension, diabetes, coronary heart disease, or smoking. Of the APOs studied, only HDP was significantly associated with HF with a fully adjusted odds ratio (OR) of 1.75 (95% CI, 1.22-2.50), and with HF with preserved ejection fraction in fully adjusted models (OR, 2.06; 95% CI, 1.29-3.27). In mediation analyses, hypertension explained 24% (95% CI, 12%-73%), coronary heart disease 23% (95% CI, 11%-68%), and body mass index 20% (95% CI, 10%-64%) of the association between HDP and HF. Conclusions and Relevance: In this large cohort of postmenopausal women, HDP was independently associated with incident HF, particularly HF with preserved ejection fraction, and this association was mediated by subsequent hypertension, coronary heart disease, and obesity. These findings suggest that monitoring and modifying these factors early in women presenting with HDP may be associated with reduced long-term risk of HF.