Cost analysis of hidden hepatitis D virus infection in Spain

Introduction: A significant percentage of patients coinfected with hepatitis B virus (HBV) and hepatitis D virus (HDV) are undiagnosed. Coinfected patients progress to advanced liver disease faster than HBV monoinfected patients, thereby consuming more healthcare resources. The aim was to perform an analysis to determine the cost of hidden HDV infection in Spain.

Methods: An analytical model was developed to estimate the prevalence of hidden HDV infection with/without advanced liver disease at the time of diagnosis. An epidemiological flow chart was established to quantify undiagnosed chronic hepatitis D patients. The percentages of patients with compensated cirrhosis (CC), decompensated cirrhosis (DC), hepatocellular carcinoma (HCC) and requiring liver transplantation (LT) and their annual costs were subsequently obtained from the literature. Direct healthcare costs were considered within a time horizon of 1 year. For patients without advanced disease, the consumption of healthcare resources was obtained from a experts panel.

Results: A total of 2,180 patients with hidden HDV infection were estimated; of these, 1,188 (54%) had advanced liver disease (29%-CC, 57%-DC, and 8%-HCC) or underwent LT (6%), and 992 (46%) patients did not have advanced disease. The total annual cost of hidden HDV would be euro 17.8 million (euro 16.9 million with advanced disease and euro 882,400 for those without).

Conclusions: Hidden HDV infection represents a high economic burden in Spain due to the rapid progression of liver disease in affected patients. These results highlight the importance of early diagnosis to prevent future clinical and economic burden related to liver disease progression.