Introduction

Chronic low-grade inflammation, known as inflammageing, has been implicated in the pathogenesis of various digestive diseases. However, large-scale systematic evaluations of the association between inflammageing biomarker profiles and digestive system disorders remain scarce. Understanding these associations may have important implications for early detection and intervention strategies.

Aims & Methods

Leveraging the multidimensional data from the UK Biobank, this study aimed to investigate the longitudinal relationships between circulating inflammatory markers and major digestive diseases. A total of 45,475 participants were included, with inflammageing levels calculated as the average of standardized values of four circulating inflammatory markers: TNF, IL1RN, IL18, and IL6.
Digestive disease outcomes were identified from hospital records (HES) and death registries, covering 25 major diagnoses, including gastroesophageal reflux disease (GERD), inflammatory bowel disease (IBD), and non-alcoholic fatty liver disease (NAFLD). Cox proportional hazards models were used to estimate hazard ratios (HRs), adjusting for age, sex, BMI, smoking, and other potential confounders.
In addition, Mendelian randomization (MR) analysis was conducted using GWAS data derived from inflammageing scores to evaluate potential causal effects on digestive outcomes. Mediation and subgroup analyses were performed to explore possible mediating factors.

Results

In the Cox regression analysis, 22 out of 25 digestive outcomes showed significant associations with baseline inflammageing levels (Bonferroni-corrected P < 0.05), with HRs ranging from 1.2 to 2.4.
Mediation analysis identified neutrophil counts and LDL-C as important mediators in these associations, suggesting potential biological pathways linking inflammageing to digestive disease development.

Conclusion

Elevated baseline inflammageing levels were significantly associated with a wide spectrum of digestive system diseases. The findings highlight a potential mechanistic role of systemic inflammation in digestive disease pathogenesis. The use of inflammageing-related biomarkers may aid in early identification of high-risk individuals, offering opportunities for early prevention and targeted interventions.

Introduction

Management of perianal fistulas in Crohn’s disease (CD) is challenging and requires a multidisciplinary approach, combining surgical drainage and biologic therapies, such as infliximab (IFX). Higher IFX trough concentrations have been associated with improved fistula healing rates. The subcutaneous (SC) formulation of IFX achieves 2–3 times higher and more stable trough levels compared to intravenous (IV) formulation. This study hypothesizes that SC IFX could enhance perianal fistula healing rates in CD patients.

Aims & Methods

REMSILAP study is part of the 3TLAP cohort, a French prospective multicenter observational study evaluating optimal therapeutic strategies for achieving clinical and radiological remission of perianal fistulas in CD at 12 months post-surgical drainage. The REMSILAP substudy focuses specifically on patients receiving SC IFX. Patients who received SC IFX after or within six months prior to surgical drainage were included. Baseline was defined as the day of surgical drainage. The primary outcome was the proportion of patients achieving complete clinical remission defined as Perianal Disease Activity Index (PDAI) fistula drainage subscore = 0 associated with PDAI activity restriction subscore <3 and absence of seton, and radiological remission at 12 months. Here, we present preliminary findings from REMSILAP.

Results

Among the 353 patients enrolled in the 3TLAP cohort, 54 were included in REMSILAP. The cohort consisted of 61.1% male patients, with a median age of 36 years and a median disease duration of 4.5 years. Penetrating disease (B3 phenotype) was present in 40.7%, and 33.3% had a history of surgical resection. At baseline, 40.7% of patients had quiescent disease regarding Harvey-Bradshaw index, while 5.6% had severe disease activity. Biologic exposure prior to inclusion was noted in 42.6%. Surgical drainage, with seton placement, was performed in 74.1% of patients. Forty-eight patients (88%) initiated SC IFX treatment after surgical drainage. Of the patients receiving SC IFX, 50% transitioned to SC IFX after less than three IV infusions. Among those on IV IFX at baseline, 20.4% were receiving a 10 mg/kg dose. Forty-three patients (79.6%) received SC IFX in combination with immunomodulators (azathioprine, methotrexate, or 6-mercaptopurine). The median duration of SC IFX treatment was 13.1 months, with treatment maintained for 67.5% of the follow-up period (mean: 19.3 ± 11.3 months). Forty-three patients (79.6%) were treated with a stable dose of 120 mg/14 days and 6 patients (11.1%) had an intensification of SC IFX dosage to 120mg / 7 days. At 12 months, 42 patients were evaluable for clinical outcomes. Complete clinical healing at 12 months was achieved in 11 patients (27.5%) and association of PDAI restriction subscore <3 and drainage subscore = 0 was found in 18 patients (42.9%). Thirteen patients (34.2%) from the 25 patients who had received at least 6 months of SC IFX treatment showed clinical healing at 6 months. Out of the 26 patients treated with at least 12 months of SC IFX treatment, clinical healing was achieved in 16 patients (61.5%) at 12 months. Among the 11 patients with clinical healing at 12 months, 8 (72.2%) were treated with SC IFX treatment following more than three IFX IV infusions. None of the 11 patients with available MRI date showed radiological healing at 12 months.

Conclusion

Subcutaneous infliximab following surgical drainage of Crohn’s disease perianal fistula demonstrates high treatment persistence and promising rates of fistula healing.

Disclosure

This study was funded by Celltrion Healthcare France