Prevalence and characterization of heart failure in a population of integrated care users
Authors: Gavina C , Seabra Carvalho D , Valente F , Bernardo F , Santos Araujo C , Taveira Gomes T 
Published: October 2021

Abstract

Introduction
Heart failure (HF) is a clinical syndrome caused by structural and functional cardiac abnormalities resulting in impairment of cardiac function, entailing significant morbi-mortality. HF is an age-dependent entity associated with cardiovascular (CV) risk factors such as type 2 diabetes (T2D).

Purpose
Estimate the prevalence of HF and its subtypes, and characterize HF in a population of integrated care users.

Methods
Non-interventional cross-sectional study performed in healthcare centre that provides primary and secondary care. All adult patients at 31/12/2019 were included. Echocardiographic parameters [left ventricle ejection fraction (LVEF) and evidence of structural heart disease] and elevated level of natriuretic peptides were used to define two HF phenotypes: i) HF with reduced ejection fraction (HFrEF, LVEF ≤40% and either NT-proBNP ≥400pg/mL (≥600pg/mL if atrial fibrillation (AF)/flutter) or BNP ≥100pg/mL (≥125pg/mL if AF/flutter)and ii) HF with non-reduced ejection fraction (HFnrEF), that encompasses both HFpEF (LVEF ≥50% and either NT-proBNP ≥200pg/mL (≥600pg/mL if AF/flutter) or BNP ≥100pg/mL (≥125pg/mL if AF/flutter) in the presence of at least one structural cardiac abnormality) and HF mid-range ejection fraction (HFmEF, LVEF within ]40, 50% [and either NT-proBNP ≥200pg/mL (≥600pg/mL if AF/flutter) or BNP ≥100pg/mL (≥125pg/mL if AF/flutter) in the presence of at least one structural cardiac abnormality). The significance threshold was set at P≤0.001.

Results
We analysed 126636 patients with mean age of 52.2 (SD=18.3) years, 57% (N=72290) were female. The prevalence of HF was 2.1% (N=2700). HF patients mean age was 74.0 (SD=12.1) years and 51.6% (N=1394) were female. Regarding HF subtypes, HFpEF accounted for 65.4% (N=1765), 16.1% (N=434) had HFmEF and 16.3% (N=439) had HFrEF. Patients with HFrEF were younger (P&lt;0.001) and had a history of myocardial infarction more frequently (P&lt;0.001) comparing to HFnrEF, with no other significant differences between HF groups. HFrEF patients were more frequently prescribed CV medications than HFnrEF patients, namely antiplatelet agents, ACE inhibitors (55.6% vs 32.7%, P&lt;0.001), beta blockers (79.3 vs 55.8%, P&lt;0.001) and aldosterone receptor antagonists (48.7 vs 8.3%, P&lt;0.001).
T2D was present in 44.7% (N=1207) of HF patients. CKD was more frequently present in T2D vs non-T2D HF patients at every stage (P&lt;0.001) as well as stroke, peripheral artery disease and microvascular disease (P&lt;0.001) (Table 1).

Conclusions
In this cohort, considering a contemporary definition, HF prevalence was 2.1%; HFrEF accounted for 16.3% of cases, with similar clinical-epidemiological profile previously reported in the literature. Our study revealed a high prevalence of patients with HFpEF (65.4%), raising awareness for the increasing prevalence of this entity in cardiology practice. These results may guide local and national health policies and strategies for HF diagnosis and management.

Funding Acknowledgement
Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): AstraZeneca, Produtos Farmacêuticos Lda Table 1. HF Patient Characteristics by subtype