Abstract Background As the growing global burden of inflammatory bowel disease (IBD), with complex treatment challenges and significant impacts for both individual health and health care systems, there is an urgent need for sustainable solutions. Align with one of the five ECCO REACH strategies of “Attain sustainable IBD care”, planetary health diet (PHD) is a low-cost, widely accessible, and environmentally sustainable intervention. We are aiming to assess whether better PHD adherence associates with reductions in both adverse clinical outcomes in IBD and negative environmental impact of the diet. Methods This study included 1,455 IBD participants from UK Biobank (UKB) and 205 from the Omics, Nutrition, and Environment Synthesis for IBD (ONE-IBD) cohort for validation. Dietary intake was recorded by repeated 24-hour dietary recall and semi-quantitative food frequency questionnaire, and seven varied PHD adherence algorithms were evaluated. Environmental impact was quantified using life cycle assessment-derived dietary carbon footprint metrics. Outcomes were IBD-related surgery, colorectal cancer (CRC), and all-cause mortality in UKB cohort, while readmission and recurrence in ONE-IBD cohort. Cox models were applied to estimate the hazard ratio (HR) and 95% confidence intervals (CIs). Results Over 10.5 years median follow-up in UKB, there were 191 incident IBD-related surgeries, 78 CRC cases, and 232 deaths. Among evaluated algorithms, Knuppel (HR per SD = 0.74, 95% CI: 0.61-0.89), Kesse-Guyot (HR per SD = 0.67, 95% CI: 0.56-0.82), Cacau (HR per SD = 0.79, 95% CI: 0.65-0.96), and Hanley-Cook (HR per SD = 0.80, 95% CI: 0.66-0.98) were inversely associated with IBD-related surgery risk (Fig.1D (a)). While the trend was not statistically significant, estimates for CRC and mortality were also below one. All algorithms correlated with reduced carbon footprint (Pearson r: -0.061 to -0.468, P 0.05). Legume/potato components showed paradoxical positive associations with surgery risk. A modified Knuppel-based algorithm showed comparable protection against surgery risk (HR per SD = 0.73, 95% CI: 0.60-0.89) with strengthened correlation with environmental benefits (r = -0.244, P 0.001, Fig.1D (b)). In validation ONE-IBD cohort, the results maintain robustness with inverse association between risk of readmission, dietary carbon footprint and PHD adherence for modified algorithm (HR per SD = 0.80, 95% CI: 0.65-1.00; r = -0.116, P = 0.007; Fig.1D (c-d)). Moreover, mechanism of how PHD influences IBD prognosis may related to improvement of intestinal barrier integrity and intestinal fibrosis. Conclusion Greater PHD adherence is associated with better IBD prognosis and environmental benefits. Our findings suggest PHD as a green and accessible means for sustainable IBD management. Conflict of interest: Dan, Lintao: No conflict of interest Shu, Haiting: I disclose no relevant conflict of interest. Sun, Yuhao: No conflict of interest Wellens, Judith: No conflict of interest Chen, Yang: No conflict of interest Deng, Minzi: No conflict of interest Yao, Jialu: No conflict of interest Ruan, Xixian: No conflict of interest Yanai, Henit: Grant: Pfizer, ISF Personal Fees: AbbVie, Janssen, Pfizer, Takeda, Bristol Myers Squibb, and Elly Lilli. Li, Xue: No conflict of interest Siegmund, Britta: Grant: Pfizer Other: Consultant: Abbvie, Abivax, Boehringer Ingelheim, Bristol Myers Squibb, Dr. Falk Pharma, Eli Lilly, Endpoint Health, Galapagos, Janssen/Johnson & Johnson, Materia Prima, MSD, Pfizer, Takeda, Wedbush Securities. Speaker: Abbvie, AlfaSigma, Bristol Myers Squibb, CED Service GmbH, Dr. Falk Pharma, Eli Lilly, Ferring, Galapagos, Janssen/Johnson & Johnson, MD Education, MSD, Pfizer, Tr1xBio. Wang, Xiaoyan: No conflict of interest Magro, Fernando: Fernando Magro served as speaker and received honoraria from Abbvie, Arena, Biogen, Bristol-Myers Squibb, Falk, Ferring, Hospira, Janssen, Laboratórios Vitoria, Pfizer, Lilly, Merck Sharp & Dohme, Sandoz, Takeda, UCB, Vifor. Dr. Chen, Jie: No conflict of interest
Dan et al. (Thu,) studied this question.