Factors associated with delayed diagnosis of hepatitis B in southeastern Sydney

Hepatitis B virus (HBV) remains a public health challenge, with chronic HBV infection leading to advanced liver disease complications, including decompensated cirrhosis (DC) and hepatocellular carcinoma (HCC). Prevention of HBV-related DC and HCC relies on effective interventions, particularly antiviral therapy, with late HBV diagnosis a missed opportunity for earlier introduction. This study investigates factors associated with late HBV diagnosis in a large area of Sydney, New South Wales (NSW), Australia.

This study used a subset of an existing population-based linked dataset, consisting of all HBV and hepatitis C notifications in NSW, linked to hospital admission data and the National HIV Registry. DC and HCC diagnoses were based on the first hospitalisation for each event. Late diagnosis was defined as HBV notification at or within 2 years of DC or HCC diagnoses. Cross-tabulation and unadjusted and adjusted logistic regression analyses were performed to assess the association between late HBV diagnosis and demographic, temporal, geographic and clinical factors.

Between 2002 and March 2022, 10,910 individuals in the South Eastern Sydney Local Health District were notified with HBV, with 296 (3%) diagnosed with DC or HCC. Late diagnosis occurred in 102 (34%) of these individuals, and was more common in females (43%) than in males (31%), in individuals born between 1945 and 1964 (55%), and in those born in West/South Asia (43%). Female sex was the only factor independently associated with late HBV diagnosis (adjusted odds ratio [aOR] 1.92, 95% CI 1.08-3.42). There were trends towards associations with late HBV diagnosis for birth cohort ≥1965 (aOR 2.02, 95% CI 0.85-4.82), overseas birth (aOR 1.92, 95% CI 0.96-4.01), history of alcohol use disorder (aOR 2.72, 95% CI 0.86-8.96) and year of DC or HCC diagnosis (aOR 0.57, 95% CI 0.28-1.16 2016-2021 vs 2001-2008).

One-third of people with HBV-related advanced liver disease complications are diagnosed late, reducing opportunities for effective interventions. Strategies to enhance earlier HBV diagnosis are required to reduce HBV burden and advance elimination efforts. Local strategies should aim to engage older migrants from West and South Asia, ensuring equity of access for women in this cohort. These findings underscore the importance of localised data and the benefits of data linkage.