Increased Risk of Environmental and Endemic Infectious Diseases in Sjögren's Disease: A Retrospective Analysis (2015-2023)

Objective: Sjögren's disease (SjD) is a chronic autoimmune disease with a complex etiology, where pathogens may influence disease development or progression. Although SjD is not communicable, environmental and endemic pathogen exposures may influence its onset or progression. This study assessed the prevalence and patterns of infectious diseases (IDs) in SjD compared to sicca symptom and autoimmune disease controls. Methods: This retrospective, cross-sectional study utilized 2015 to 2023 data from the University of Utah UHealth, analyzing 3,826 patients with SjD and age- and sex-matched controls. ID diagnoses were classified using International Classification of Diseases, Tenth Revision (ICD-10) codes, and odds ratios (ORs) were calculated to identify significant differences in ID prevalence between cases and control cohorts. Unique infections, reinfections, and temporal analyses were performed. Hierarchical cluster analysis identified common and unique patterns of ID diagnoses across different patient groups. Results: Patients with SjD had an average of 5.30 ± 8.00 unique ID diagnoses compared to 4.86 ± 6.15 in controls (P < 0.001). Infections and reinfections were more frequent in SjD, particularly bacterial and fungal. Younger age at SjD diagnosis was associated with increased infections and reinfections. Anti-SSA/Ro positivity correlated with higher infection and reinfection rates. One hundred thirty-four ICD-10 codes showed significant differences in prevalence (based on ORs), with increased bacterial (eg, Mycobacterium, Streptococcus spp.), viral (eg, herpesviruses, molluscum contagiosum), fungal (eg, Candida, Aspergillus), and parasitic (onchocerciasis) infections in SjD. ID profiles in SjD strongly aligned with systemic lupus erythematosus. Conclusion: These findings suggest increased prevalence and recurrence of infections in SjD a potential role in disease onset and progression. Further studies are needed to clarify infection-related mechanisms and identify therapeutic targets.