Long-term outcomes in women diagnosed with heart failure in connection to delivery

Abstract Background Heart failure (HF) among young patients may be from various causes, often triggered by heightened physical demands like pregnancy. Data regarding outcomes of women diagnosed with HF in conjunction to pregnancy and delivery are varied. There remains a notable gap in understanding the outcomes observed in women diagnosed with heart failure in conjunction with delivery. Also, long-term follow-up studies are crucial to elucidate the impact of pregnancy-associated HF on future cardiovascular. Purpose To study the interplay between pregnancy, HF, and subsequent cardiovascular risk. Method Using the personal identification numbers (PINs) that all individuals in Sweden have enables linkage of data between different registers. Data from the National Patient Register (NPR), Swedish Medical Birth Register (MBR) and the Cause of Death Register were also used. All women 18 to 50 years of age registered in the in MBR in the period 1st January 1997 to 31st December 2019 were included. Women with first-time HF in relation to delivery were identified using the international classification code for diseases (ICD-10) I50, I42, I43 and 090.3 together with co-morbidities. Every patient was compared with 5 controls without HF from the Total Population Register matched on age at delivery and calendar year of delivery. Outcomes: all-cause mortality, and any cardiovascular disease (CVD) diagnosed during the observation time. Results A total of 286 cases and 1,430 controls were included. The prevalence of comorbidities at baseline for both patients and controls was low; congenital heart disease (1.4%, vs. 0%), pulmonary hypertension (1.0% vs. 0%), valvular heart disease (5.9% vs. 0%), myocardial infarction 0.7% vs. 0%), arrhythmia (5.9% vs. 0%), hypertension (6.3 % vs. 0.1%), (all p<0.05). Preeclampsia prior to HF diagnosis had 31% of patients vs. 0.2% of controls (p<0.001). Patients exhibited higher mortality rates at 4.9% during median follow up 9.0 (IQR 5.6-13.0) years vs. 0.3%, median follow up 9.4 (6.2-13.5) years and hazard ratios (HR) for all-cause mortality HR (95% CI) of 18.20 (5.99 - 55.31) (p<0.001) compared to controls. During median follow up of 3.2 (0.0-9.2) years 60.1% of patients were diagnosed with CVD both at in-/out-patient settings compared with 4.1% in controls during 9.4 (5.8-13.5) years of follow up. Comparing patients with controls the HR (95% CI) was 22.24 (16.50 - 29.96) p<0.0001 for CVD diagnosis during follow-up, see Figure 1. Conclusion In conjunction with delivery, and in the years thereafter, women with heart failure diagnosis had more than eighteen times higher risk of mortality than women without heart failure. The risk of CVD event in the heart failure group is highest in conjunction with delivery. Figure 1. Cumulative incidence functions for all-cause mortality, CVD in- or out-patient visit adjusted for death as competing risk, comparing cases with controls.