Letter to the Editor: Unanswered questions about hepatitis B virus infection in patients with COVID-19.

To the editor,

We read with great interest the study written by Yip et al.[ ] The researchers answered some previously unanswered questions about COVID‐19 patients with HBV infection and thus had clear clinical implications. We think that some questions still need to be answered further on this topic.

The primary endpoint of this study was all‐cause mortality. Notably, the severity of disease in COVID‐19 patients was not discussed. The results of current studies on whether HBV infection increases disease severity in patients with COVID‐19 have been inconsistent, even in some studies with large samples from China.[ , ] In fact, these studies also reported similar mortality in COVID‐19 patients with or without HBV infection. Considering that viral interference and immune dysfunction may be caused by HBV infection and therefore lead to changes in the body’s response to SARS‐CoV‐2 infection,[ ] the change in disease severity over the course of COVID‐19 patients with past or current HBV infection is clinically significant.

Another question is whether the presence of HBV‐associated cirrhosis may associate with poor outcomes in COVID‐19. Although liver cirrhosis was found to be associated with a higher risk of mortality in the current study, the cause of cirrhosis was not distinguished. It also did not distinguish the clinical stages of current HBV infection. A recent study proved that the stage of liver disease is strongly associated with COVID‐19 mortality.[ ] For patients with advanced liver disease caused by HBV infection, whether the disease severity and mortality of COVID‐19 are different from those of chronic hepatitis (or other etiologies) is still unknown. However, this would have significant clinical value in the monitoring and treatment of patients.

In conclusion, we believe that the answers to the above questions can provide a more comprehensive understanding of the relationship between HBV infection and COVID‐19.

CONFLICT OF INTEREST

Nothing to report.

AUTHOR CONTRIBUTIONS

X‐H.L. and K.D. were responsible for the study concept and design, collection of the literature, drafting of the manuscript. J‐L.Y. was responsible for the study concept and design, critical revision of the manuscript for important intellectual content. All authors approved the final draft manuscript.