Diagnosed Patients With Chronic Hepatitis B and Delta Virus in Italy in 2024: An Estimation From a National Real-World Database

Background and Aims: Hepatitis B (HBV) and Hepatitis Delta virus (HDV) infection have undergone significant changes in Italy over the past few decades, but reliable and updated prevalence of chronic hepatitis B (CHB) and Delta (CHD) data are lack- ing. The aim of the study was to describe the epidemiology of CHB and CHD in Italy in 2024, based on real-world data. Methods: The number of patients with a healthcare expenditure exemption for CHB (016.070.32) and CHD (016.070.33) was obtained from 21 Regional Health Authorities. To understand how many CHB or CHD patients did not have these specific ex- emptions, a survey was conducted in 30 Gastroenterology, Hepatology and Infectious Diseases Units across the country. Results: Health Authorities data reported 67 514 and 5216 subjects with an exemption for CHB and for CHD, respectively. However, among 6775 CHB and 504 CHD patients, only 60.3% and 55.7% of them had the specific exemption, respectively. Based on these results, we estimated 111 960 (95% CI: 109 780–114 240) CHB and 9360 (95% CI: 8690–10 150) CHD patients, with a prev- alence of 0.22% and 0.019% of the adult overall population. Moreover, anti-HDV prevalence was 7.7% from this cohort. Conclusion: Our study provides a plausible estimate of the current number of adult patients diagnosed with CHB and CHD in Italy and may be considered the basis for decision-making health policies.