Influenza Vaccination in Patients With Congenital Heart Disease in the Pre-COVID-19 Era: Coverage Rate, Patient Characteristics, and Outcomes

Influenza vaccination is the most commonly recommended immune prevention strategy. However, data on influenza vaccination in patients with congenital heart disease (CHD) are scarce. In this study, our goals were to: (1) measure vaccination coverage rates (VCRs) for influenza in a large cohort of children, adolescents, and adults with CHD; (2) identify patient characteristics as predictors for vaccination; and (3) investigate the effect of influenza vaccination on hospitalization. A nationwide cohort study in Belgium included 16,778 patients, representing 134,782 vaccination years, from the Belgian Congenital Heart Disease Database Combining Administrative and Clinical Data (BELCODAC). Data over 9 vaccination years (2006-2015) were used, and patients were stratified into 5 age cohorts: 6 months to 4 years; 5-17 years; 18-49 years; 50-64 years; and 65 years and older. In the respective age cohorts, the VCR was estimated to be 6.6%, 8.0%, 23.9%, 46.6%, and 72.8%. There was a steep increase in VCRs as of the age of 40 years. Multivariable logistic regression showed that higher anatomical complexity of CHD, older age, presence of genetic syndromes, and previous cardiac interventions were associated with significantly higher VCRs. Among adults, men had lower and pregnant women had higher VCRs. The association between influenza vaccination and all-cause hospitalization was not significant in this study. The influenza VCR in people with CHD is low, especially in children and adolescents. Older patients, particularly those with complex CHD, are well covered. Our findings should inform vaccination promotion strategies in populations with CHD. La vaccination contre la grippe est la stratégie de prévention immunitaire la plus couramment recommandée. Cependant, les données sur la vaccination antigrippale chez les patients atteints de cardiopathie congénitale (CC) sont rares. Dans cette étude, nos objectifs étaient de : (1) mesurer les taux de couverture vaccinale (TCV) contre la grippe dans une grande cohorte d'enfants, d'adolescents et d'adultes atteints de CC; (2) identifier les caractéristiques des patients en tant que facteurs prédictifs de vaccination; (3) étudier l'effet de la vaccination contre la grippe sur l'hospitalisation. Une étude de cohorte nationale menée en Belgique a regroupé 16 778 patients, représentant 134 782 années de vaccination à partir de la BelgianCongenital Heart DiseaseDatabase CombiningAdministrative andClinical Data (BELCODAC). Des données