Immunogenicity of COVID-19 Vaccines in Patients Under Immunosuppressive Therapy: Insights Into Antibody Response and Gender Differences
The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has impacted millions worldwide. Patients with autoimmune rheumatic diseases (ARDs) may exhibit attenuated responses to vaccination secondary to immunosuppressive therapy, potentially resulting in reduced vaccine effectiveness. This study investigates the immunogenicity of COVID-19 vaccines in patients with ARDs and evaluates antibody responses and the factors associated with such responses. We included 91 patients with rheumatologic diseases receiving immunosuppressive therapy and attending rheumatology clinics in Bandar Abbas, Iran. All had received two or three doses of a COVID-19 vaccine 6 months prior to enrollment. Antibody levels were measured using plaque reduction neutralization tests. We also collected information on demographics, clinical status, and current medication use. All statistical analyses were performed using SPSS version 21. Females constituted 89% of the participants. The majority had received the Sinopharm vaccine. Gender differences were observed, with males showing higher neutralizing antibody levels. No significant associations were detected between antibody levels and age, vaccine type, or medication use, except for adalimumab and etanercept, which showed a positive association with neutralizing antibodies. While most ARD patients demonstrated a detectable response, gender appeared to influence antibody levels, with females exhibiting a weaker response. Vaccine type did not influence antibody levels, and medication use did not show consistent correlations with antibody responses. These findings are consistent with the literature suggesting that vaccine efficacy may be reduced in immunocompromised populations, further supporting individualized vaccination strategies. COVID-19 vaccines provide incomplete protection in patients with ARDs, and immunosuppressive therapy and gender may affect vaccine efficacy. Personalized vaccination schedules, including booster doses, are recommended to improve protection in this population. Further studies are needed to refine vaccination strategies for immunocompromised patients, with the aim of reducing the burden of severe illness and improving public health.