Impact of COVID-19 Vaccination and Estrogen on the Severity of Rheumatoid Arthritis in Postmenopausal Iraqi Females

Background: Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder with multifactorial etiology. Hormonal factors and immune-modulating events, such as vaccination, may influence disease activity. Objective: To evaluate the effect of COVID-19 vaccination and serum estrogen levels on RA severity in postmenopausal Iraqi females, with emphasis on inflammatory biomarkers and cytokine profiles. Methods: A case-control study was conducted on 40 vaccinated RA patients and 44 age-matched healthy controls. Serum ESR, CRP, RF, IL-8, IL-10, and estrogen levels were measured using sandwich ELISA. Demographic characteristics and BMI were recorded. Statistical analysis examined correlations between these parameters and RA severity. Results: RA patients demonstrated significantly higher ESR, CRP, RF, IL-8, and estrogen levels than controls (p < 0.05), with a positive correlation to disease severity. IL-10 levels were elevated but not statistically associated with severity (p = 0.1009). Postmenopausal RA patients had markedly elevated estrogen compared to expected physiological ranges. Conclusion: COVID-19 vaccination and elevated estrogen levels are significantly associated with increased inflammatory markers and RA severity in postmenopausal Iraqi women. These findings suggest the need for closer post-vaccination monitoring in high-risk autoimmune populations.