Unhealthy Behaviours and All‐Cause Mortality Among People With Chronic Hepatitis B, With and Without Hepatitis Delta ( <scp>ANRS CO22 HEPATHER</scp> )

People infected with both hepatitis B virus (HBV) and hepatitis Delta virus (HDV) face a higher mortality risk than those mono-infected with HBV. As unhealthy behaviours can influence liver disease progression, we compared the effects of various behavioural factors on all-cause mortality among people with chronic hepatitis B (CHB), with or without chronic hepatitis Delta (CHD). We used 5-year follow-up data from people with CHB participating in the French ANRS CO22 HEPATHER cohort. A Cox proportional hazards model helped determine whether the pattern of risk factors for all-cause mortality differed according to CHD status. Of the 3884 people included, 183 had CHD and 154 died during follow-up. After multivariable adjustment, daily soft drink consumption significantly increased mortality risk in people with CHD and almost reached significance in those without CHD (adjusted hazard ratio (aHR) [95% CI]: 6.09 [2.40-15.48], p < 0.001, and 1.58 [0.97-2.56], p = 0.066 respectively). Moreover, past or current unhealthy alcohol use and tobacco smoking were both associated with a higher risk of mortality in all people with CHB (1.74 [1.09-2.79], p = 0.020, and 1.61 [1.13-2.31], p = 0.009 respectively). Daily soft drink consumption significantly increased all-cause mortality in people with CHD. Unhealthy alcohol use and tobacco smoking were associated with a higher mortality risk in all people with CHB. Education about healthy eating and support for smoking cessation and alcohol reduction could greatly improve health and survival of people with CHB, with and without CHD.