Association between dietary index for gut microbiota and chronic kidney disease: A cross-sectional study from U.S. population

Objective: Emerging evidence suggests that diet modulates gut microbiota, which in turn influences chronic kidney disease (CKD) progression. This study investigates the association between the newly proposed Dietary Index for Gut Microbiota (DI-GM) and the prevalence and prognosis of CKD.

Methods: This cross-sectional study analyzed data from the U.S. National Health and Nutrition Examination Survey 2007–2020. DI-GM scores were calculated based on dietary intake of 14 food components, categorized as beneficial or unfavorable. Weighted linear regression model, logistic regression model, and restricted cubic spline analysis were used to assess the associations of DI-GM with CKD.

Results: The prevalence of CKD among 28,512 participants was 17.4 %. Higher DI-GM was negatively associated with CKD prevalence (OR = 0.967, 95 %CI: 0.939–0.995, p = 0.026) and with very high-risk prognosis (OR = 0.877, 95 %CI: 0.821–0.937, p < 0.001). Beneficial DI-GM components were significantly associated with lower CKD risk (OR = 0.928, 95 %CI: 0.892–0.966, p < 0.001), while no significant association was observed for unfavorable components. Higher DI-GM and beneficial DI-GM levels were linearly associated with improved CKD prognosis (p for trend <0.001). Coffee and fiber were primary contributors to both the prevalence and prognosis of CKD, while whole grains primarily impacted its prognosis.

Conclusions: Higher DI-GM, driven by beneficial dietary components, is associated with reduced CKD prevalence and improved prognosis. These findings suggest that promoting beneficial dietary patterns to enhance gut microbiota may play a pivotal role in CKD management.