Impact of elective surgery on tumor necrosis factor-α, interleukin-6 and quality of life in uncomplicated diverticular disease

Aim: Growing evidence suggests that immune/inflammatory pathways play a crucial role in the persistence of symptoms in diverticular disease (DD). We hypothesize that chronic diverticulitis triggers a self-sustained inflammatory status which can be detected by measuring the levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The aim of this study was to investigate the systemic levels of TNF-α and IL-6 before and after elective surgery in patients with DD, and their relationship with the gastrointestinal quality of life index (GIQLI) score. Method: This prospective multicentric study enrolled patients from the Diverticular Disease Registry (DDR-Trial, NCT04907383). All adult patients diagnosed with symptomatic uncomplicated diverticular disease (SUDD), uncomplicated recurrent diverticulitis (URD) and smouldering diverticulitis (SmD) between 1st December 2022 and 31st December 2023 were included in this study. Exclusion criteria were as follows: no surgery, a concurrent chronic immunomodulated systemic disease, a SARS-CoV-2-positive test in the previous 12 months, a history of cancer in the previous 5 years, patients treated with immunomodulators, an American Society of Anesthesiologists category of class IV, and complicated acute diverticulitis. Results: Seventy-two patients were included: 52 (72%) with URD, 11 (15%) with SUDD, and nine (13%) with SmD. The median postsurgery – presurgery (Δ)IL-6 and ΔTNF-α levels were −16.8 and −17.3 pg/mL, respectively (p < 0.001 for both; Wilcoxon test). Spearman correlation revealed a significant, negative association between the ΔGIQLI and the ΔIL-6, as well as the ΔTNF-α (p < 0.001 for both). Greater reduction in the levels of IL-6 and TNF-α following surgery are associated with higher GIQLI scores postoperatively. Conclusion: Patients with chronic diverticulitis may experience persistent systemic inflammation driven by a colonic trigger. Surgical removal of this trigger appears to enhance GIQLI outcomes reducing IL-6 and TNF-α across surgery.