Evaluation of Hepatitis B Vaccination Status and Factors Affecting Response to Vaccination in HIV/AIDS Patients

Objective: Chronicity of acute HBV infection is higher in people living with HIV (PLWH) than in the general population. HIV/HBV coinfection has a higher risk of rapid progression to cirrhosis and liver-related death than in solely HBV-infected patients. Therefore, vaccination against HBV is recommended. In this study, we aimed to evaluate hepatitis B vaccination rates and the factors affecting response to the vaccine in PLWH. Methods: Outpatient follow-up files and laboratory test results at the hospital information system of 1394 patients aged >18 years diagnosed with HIV/AIDS and followed between January 1, 2007, and January 1, 2022, were evaluated retrospectively. Results: Of the PLWH, 81 (5.8%) had chronic hepatitis B infection, 114 (8.2%) had isolated anti-HBc IgG positivity, and 274 (19.6%) had a previous condition. 248 (17.7%) of the PLWH had been vaccinated before HIV/AIDS diagnosis. HBsAg, anti-HBc IgG and anti-HBs were negative in 673 PLWH. A total of 352 (44.7%) PLWHs were vaccinated, consisting of 63 (55.2%) of 114 PLWHs with isolated anti-HBc IgG positivity and 289 (42.9%) of 673 PLWHs with negative HBV serology. Immunity developed in 282 (84.1%) of those vaccinated. We found that the main factor determining the immune response was the CD4+ T lymphocyte count at the time of diagnosis, and there was a significant increase in immune response since 2015 when the recommendation of antiretroviral therapy independent of the CD4+ T lymphocyte level was implemented. We observed that comorbidities, age, gender, and sexual orientation did not significantly affect the vaccine response. Conclusion: Vaccination is critical in PLWH, and we observed that the ideal time for vaccination in those with negative HBV serology is when the CD4+ T lymphocyte count is >200 cells/mm³ and the viral load is suppressed. It should be considered that the vaccination rate and immune response will increase with the support of vaccination outpatient clinics, where vaccination status is closely monitored by healthcare personnel. Keywords: HIV/AIDS, hepatitis B vaccine, vaccination, vaccine respons