The Hospital Burden of Flu in Italy: a retrospective study on administrative data from season 2014-2015 to 2018-2019.

BACKGROUND: Every year in Italy, influenza affects about 4 million people. Almost 5% of them are hospitalised. During peak illness, enormous pressure is placed on healthcare and economic systems. This study aims to quantify the clinical and economic burden of severe influenza during 5 epidemic seasons (2014-2019) from administrative claims data. METHODS: Patients hospitalized with a diagnosis of influenza between October 2014, and April 2019, were analyzed. Clinical characteristics and administrative information were retrieved from health-related Administrative Databases (ADs) of 4 Italian Local Health Units (LHUs). The date of first admission was set as the Index Date (ID). A follow-up period of six months after ID was considered to account for complications and re-hospitalizations, while a lookback period (2 years before ID) was set to assess the prevalence of underlying comorbidities. RESULTS: Out of 2,333 patients with severe influenza, 44.1% were adults ≥ 65, and 25.6% young individuals aged 0-17. 46.8% had comorbidities (i.e., were at risk), mainly cardiovascular and metabolic diseases (45.3%), and chronic conditions (24.7%). The highest hospitalization rates were among the elderly (≥ 75) and the young individuals (0-17), and were 37.6 and 19.5/100,000 inhabitants/year, respectively. The average hospital stay was 8 days (IQR: 14 - 4). It was higher for older individuals (≥ 65 years, 11 days, [17 - 6]) and for those with comorbidities (9 days, [16 - 6]), p-value < 0.001. Similarly, mortality was higher in elderly and those at risk (p-value < 0.001). Respiratory complications occurred in 12.7% of patients, and cardiovascular disorders in 5.9%. Total influenza-related costs were €9.7 million with hospitalization accounting for 95% of them. 47.3% of hospitalization costs were associated with individuals ≥ 65 and 52.9% with patients at risk. The average hospitalisation cost per patient was € 4,007. CONCLUSIONS: This retrospective study showed that during the 2014-2019 influenza seasons in Italy, individuals of extreme ages and those with pre-existing medical conditions, were more likely to be hospitalized with severe influenza. Together with complications and ageing, they worsen patient's outcome and may lead to a prolonged hospitalization, thus increasing healthcare utilization and costs. Our data generate real-world evidence on the burden of influenza, useful to inform public health decision-making.

Costs and healthcare utilisation due to respiratory syncytial virus disease in paediatric patients in Italy: a systematic review.

OBJECTIVES: Respiratory syncytial virus (RSV) is a frequent cause of acute lower respiratory infection in children, imposing a substantial economic burden on healthcare systems. This systematic review aimed to assess the economic burden and healthcare utilisation of RSV in children aged 0-59 months in Italy. STUDY DESIGN: Systematic review. METHODS: A systematic search of PubMed, Embase, Scopus, and the International HTA Database, including studies published in English or Italian, was conducted between January 2000 and July 2022. Inclusion criteria required studies to be conducted in Italy and provide data on the economic costs and healthcare resource utilisation related to RSV infections. RESULTS: Out of 20,845 records screened, 18 articles met the inclusion criteria. Only one study provided comprehensive data on RSV disease costs, including hospitalisation, diagnostic tests, and medical procedures for infants with RSV-bronchiolitis. The mean cost per inpatient was higher for RSV-positive children (€5753.43 ± €2041.62) than that for RSV-negative children. Additionally, five studies reported a median length of hospital stay of 5 days for RSV-infected children, and four studies indicated a higher frequency of intensive care unit admissions for RSV-infected children than for those with other viral infections. CONCLUSIONS: This is the first systematic review to examine the economic burden and healthcare utilisation of RSV in children aged 0-59 months in Italy. While limited data were available, the findings underscore the urgency to conduct further research and gather additional evidence on the costs and healthcare resource utilisation associated with RSV infections. Such efforts are essential for informing the development of effective prevention strategies for paediatric RSV infections in Italy.

Cost-effectiveness for high dose quadrivalent versus the adjuvanted quadrivalent influenza vaccine in the Italian older adult population.

Objectives: To assess the cost-effectiveness of switching from adjuvanted quadrivalent vaccine (aQIV) to high-dose quadrivalent influenza vaccine (HD-QIV) in those aged ≥65 years from the Italian National Health Service perspective. Methods: We developed a decision tree model over a 1-year time-horizon to assess influenza-related costs and health outcomes. Two hospitalization approaches were considered: "hospitalization conditional on developing influenza" and "hospitalization possibly related to Influenza." The first approach considered only hospitalizations with influenza ICD-9-CM diagnosis codes. The second included hospitalizations for cardiorespiratory events possibly related to influenza to better capture the "hidden burden". Since comparative efficacy of high-dose quadrivalent influenza vaccine versus adjuvanted quadrivalent vaccine was lacking, we assumed relative efficacy versus a common comparator, standard-dose influenza quadrivalent vaccines (SD-QIV). We assumed the relative efficacy of HD-QIV vs. SD-QIV was 24.2 and 18.2% for the first and second hospitalization approaches, respectively, based on published information. Due to lack of comparative efficacy data for aQIV vs. SD-QIV, we assumed three different scenarios: 0, 6, and 12% relative efficacy in scenarios 1, 2, and 3, respectively. Results: For the first hospitalization approach, HD-QIV was a cost-effective alternative to aQIV in all scenarios at a willingness-to-pay threshold of €30,000 per Quality Adjusted Life Years. The incremental cost-effectiveness ratios across the scenarios were €7,301, €9,805, and €14,733, respectively, much lower than the willingness-to-pay per Quality Adjusted Life Years threshold. For the second hospitalization approach, HD-QIV was a dominant alternative to aQIV across all scenarios. The robustness of the results was confirmed in one-way and probabilistic sensitivity analyses. Conclusion: Switching to HD-QIV from aQIV for the older adult in Italy would improve health-related outcomes, and would be cost-effective or cost saving.