Surgical removal of Waldeyer’s ring and long-term risk of Sjögren’s syndrome: a population-based cohort study investigating the mucosal immune link

Background: The palatine tonsils and adenoids are critical inductive sites for the mucosa-associated lymphoid tissue (MALT) system, educating B cells for salivary defense. While their removal is common, the long-term impact on mucosal autoimmunity remains unclear. We hypothesized that disrupting this lymphoid network increases susceptibility to Sjögren's syndrome (SS). Methods: Using the TriNetX US Collaborative Network (2006-2023), we conducted a retrospective cohort study matching 302,737 patients who underwent tonsillectomy/adenoidectomy with 302,737 non-surgical controls (propensity score-matched 1:1). Hazard ratios (HR) for incident SS were estimated using Cox proportional hazards models. Results: The surgical cohort exhibited a significantly elevated risk of SS (HR 1.52; 95% CI 1.23-1.87; p