Tanushree Bhatt, Snigdha Gadireddy, Pravash Budhathoki and Giovanni Franchin, Bronxcare Health System, Bronx, NY
Background/Purpose: Multiple studies have shown reduced immunogenicity of mRNA covid vaccines in patients with rheumatological disease. The waning antibody levels in this population group, whether due to the aberrant immune signatures as an inherent part of their autoimmune condition or treatment with immunosuppressive agents, suggest the possible need for earlier booster shots. This study aims to monitor the trends of anti-spike antibody levels in a minority population with a rheumatological disease on various immunosuppressive treatments and determine the level of antibody response to COVID-19 vaccines.
Methods: The study analyzed patients with varying rheumatological and musculoskeletal diseases who had completed the primary series of vaccination with either mRNA (BNT162b2 or mRNA-1273) or vector (Jannsen) vaccine. Data corresponding to demographics, clinical characteristics, vaccination type, date of vaccination, and anti-spike protein IgG antibody levels was obtained through chart review. A review of the antibody levels at random time intervals after the first (vector) or second (mRNA vaccine) vaccine doses was performed through the anti-Sars-Cov-2S enzyme immunoassay, and an analysis of the efficacy of immune responsiveness was made. A titer greater than 2500 was considered suggestive of a robust immune response.
Results: The study consisted of 222 patients with a mean age of 61.7 years (12.99; range 21-91 years), of which 78.3% were women. Most of the patients belonged to a racially minor population group including African Americans (21%) and Hispanics (78%). 93 out of the 222 patients (41.8%) had an antibody titer greater than 2500 suggesting a strong immune response. The time interval of 3-4 months post-vaccination was associated with a significant decline in anti-spike protein antibody levels (p-values < 0.004). Blunted antibody titers were also seen in African Americans as compared to Hispanics (p < 0.01) in the multivariate logistic regression.
Conclusion: Our study shows a decline in anti-spike protein antibody titers at 3-4 months post-vaccination suggesting the necessity for potential earlier booster vaccination. It also indicates the need for vigilance in monitoring antibody levels in patients belonging to the minority population. Larger studies are needed to expand on these preliminary results and also on potential implications to black patients.