Respiratory syncytial virus in adults aged ≥ 50 years in France: a database and time-series modelling analysis...

This study aimed to quantify the burden of respiratory syncytial virus (RSV)- and influenza-attributed acute respiratory infections (ARI) in older adults in France. Modelling was applied to real-world data on ARI-attributed hospital admissions and in-hospital mortality to estimate pathogen-specific outcomes and investigate the underreporting of RSV in standard clinical practice. Additionally, healthcare resource utilisation was assessed.

This retrospective, observational cohort study used routinely collected, secondary care data from the Programme National de Médicalisation des Systèmes d'Information (PMSI) database. All patients aged ≥ 50 years with an ARI-related hospitalisation, identified through International Classification of Diseases, 10th Revision (ICD-10) coding, between July 2014 and February 2020 were included. The predicted number and annual rate of hospitalisations were calculated using a Quasi-Poisson regression model, stratified by age group. Sensitivity analyses were used to investigate cardiorespiratory hospital admissions and in-hospital mortality.

2,009,218 patients with an ARI-related hospitalisation were identified. Predicted rates of RSV- and influenza-attributable ARI hospitalisations ranged from 0.05 and 0.27 per 1000 person-years among 50-54-year-olds to 14.38 and 12.48 per 1000 person-years among ≥ 90-year-olds, respectively. Rates of in-hospital mortality were similar between the two pathogens, while RSV was predicted to account for a much larger number of cardiorespiratory hospitalisations than influenza. RSV-coded hospitalisations lasted 8-11 days across age groups, and 25.6% of 55-59-year-olds hospitalised with RSV were admitted to an intensive care unit.

These data reveal a substantial burden of RSV-related morbidity and mortality among older adults in France, demonstrating a need to prioritise RSV prevention.