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.