Real-world evidence on vaccine coverage in patients admitted for acute decompensated heart failure

Introduction Heart failure remains a severe cardiovascular condition associated with substantial morbidity and mortality, representing a major public health challenge worldwide. Vaccination is a simple, cost-effective preventive strategy that has been linked to a reduced risk of heart-failure hospitalizations. Consequently, current international guidelines recommend influenza, SARS-CoV-2, and pneumococcal vaccination for patients at increased risk of major adverse events, including those with heart failure. Purpose The aim of this study was to evaluate the vaccination status of high-risk patients hospitalized at our centre for an episode of heart failure and to identify clinical characteristics associated with vaccination coverage for influenza, COVID-19, and pneumococcal vaccines. Methods We conducted a prospective observational study including all patients admitted to the Cardiology Department for acute heart failure between September 2021 and August 2024. Clinical, laboratory, and echocardiographic variables were systematically recorded. Vaccination status was assessed for seasonal influenza, COVID-19, and pneumococcal vaccines. Comparisons between vaccinated and non-vaccinated patients were carried out using appropriate statistical tests. Results A total of 519 patients were included (mean age 75.1 ± 10.8 years; 42.4% women). The burden of major comorbidities was notably high, including hypertension (86.6%), dyslipidaemia (65.3%), diabetes mellitus (44.7%), chronic kidney disease (48.3%), chronic obstructive pulmonary disease (COPD, 32.9%), ischaemic heart disease (29.7%), atrial fibrillation (49.0%), and prior heart failure (46.0%). Most patients were in NYHA class ≥ II (83.9%) and mean left ventricular ejection fraction was 50.4 ± 14.4%. Influenza vaccination coverage reached 63.2%, pneumococcal vaccination 14.9%, and COVID-19 vaccination 95.6%. Patients vaccinated against influenza were significantly older, more frequently women, and showed a higher prevalence of hypertension, dyslipidaemia, COPD, atrial fibrillation, and previous heart failure compared with non-vaccinated patients. With regard to pneumococcal vaccination, coverage was markedly lower. Vaccinated patients showed a higher proportion of COPD and peripheral vascular disease. Although patients with prior heart failure tended to be more frequently vaccinated, this difference did not reach statistical significance. Conclusions Our findings reveal an important gap between evidence-based recommendations and real-world practice. Despite clear guideline recommendations, influenza vaccination remains suboptimal and pneumococcal coverage strikingly low in heart failure patients. Conversely, COVID-19 vaccination rates were very high, likely reflecting pandemic-related public health efforts. These results highlight the need for targeted strategies to improve routine vaccination uptake in this vulnerable population.Table 1.Baseline characteristicsTable 2.