Immunometabolic determinants of hepatitis B vaccine seroprotection among Ethiopian adults

Hepatitis B virus (HBV) remains a critical public health issue in Ethiopia, where despite vaccination efforts, significant rates of non-seroprotection exist among vaccinated adults. Dyslipidemia and chronic inflammation are emerging as important immunometabolic factors influencing vaccine-induced immunity. This study aimed to investigate the impact of lipid profiles and inflammatory markers on hepatitis B vaccine seroprotection among healthcare providers who had completed hepatitis B vaccination in the northwestern region of Ethiopia. An institution-based cross-sectional study was conducted From May 22, 2024, to January 15, 2025 involving 422 healthcare providers. Socio-demographic and clinical data were collected and venous blood samples (7–9 milliliters) were obtained from each participant. Then, immunity following complete hepatitis B vaccination (anti-HBs) was measured using enzyme-linked immunosorbent assay (ELISA). Lipid profiles (HDL-C, LDL-C, TC, and TG) were analyzed using automated clinical chemistry analyzers. C-reactive protein (CRP) levels were quantified by latex agglutination turbidimetric immunoassay. The Systemic Immune-Inflammatory Index (SII) was calculated from complete blood count (CBC) results. Prevalence ratios (PRs) were calculated with 95% confidence intervals. The overall seroprotection rate was 73.7%. The seroprotection rate among participants aged 36–55 years was 47.9%. Additionally, high seroprotection rates were observed among participants with normal body mass index (83.3%), a healthy diet (80.7%), and normal HDL levels (83.0%), although these differences were not statistically significant. On the other hand, high LDL cholesterol level (APR = 0.67; 95% CI: 0.46 to 0.97; p = 0.032) and elevated SII (APR = 0.61; 95% CI: 0.40 to 0.93; p = 0.021) were significantly associated with increased risk of seroprotection reduction. This study underscores the importance of identifying composite immunometabolic and immunoinflammatory indices to predict and potentially mitigate poor vaccine outcomes, especially in populations facing ongoing infectious and metabolic challenges.