Disparities in hepatitis B virus healthcare service access among marginalised poor populations: a mixed-method systematic review

Background: Marginalised poor populations, characterised by poverty and social exclusion, suffer disproportionately from hepatitis B virus (HBV) infections and encounter substantial disparities in access to healthcare. This has further exacerbated the global HBV burden and precluded progress towards HBV elimination. This mixed-method systematic review aimed to synthesise their utilisation and influencing factors in HBV healthcare services, including screening, vaccination, treatment, and linkage-to-care. Methods: Eleven databases were searched from their inception to May 4, 2023. Quantitative and qualitative studies examining the factors influencing HBV healthcare access among marginalised poor populations were included. A meta-analysis was conducted to synthesise the pooled rates of HBV healthcare utilisation. The factors influencing utilisation were integrated and visualised using a health disparity research framework. Results: Twenty-one studies were included involving 13,171 marginalised poor individuals: sex workers, rural migrant workers, irregular immigrants, homeless adults, and underprivileged individuals. Their utilisation of HBV healthcare ranged from 1.5% to 27.5%. Meta-analysis showed that the pooled rate of at least one dose of the HBV vaccine barely reached 37% (95% confidence interval: 0.26‒0.49). Fifty-one influencing factors were identified, with sociocultural factors (n = 19) being the most frequently reported, followed by behavioural (n = 14) and healthcare system factors (n = 11). Socio-cultural barriers included immigration status, prison history, illegal work, and HBV discrimination. Behavioural domain factors, including previous testing for sexually transmitted diseases, residential drug treatment, and problem-solving coping, facilitated HBV healthcare access, whereas hostility coping exerted negative influences. Healthcare system facilitators comprised HBV health literacy, beliefs, and physician recommendations, whereas barriers included service inaccessibility and insurance inadequacies. The biological and physical/built environments were the least studied domains, highlighting that geographical mobility, shelter capacity, and access to humanitarian health centres affect HBV healthcare for marginalised poor populations. Conclusions: Marginalised poor populations encounter substantial disparities in accessing HBV healthcare, highlighting the need for a synergistic management approach, including deploying health education initiatives to debunk HBV misperceptions, developing integrated HBV management systems for continuous tracking, conducting tailored community outreach programmes, and establishing a human rights-based policy framework to guarantee the unfettered access of marginalised poor populations to essential HBV services.