ABSTRACT

Background & aims:
Little is known about whether a novel food-based score designed to quantify dietary inflammation is associated with CKD. We conducted a cross-sectional study to assess the association between the Comprehensive Dietary Inflammatory Index (CDII) and CKD in the National Health and Nutrition Examination Survey (NHANES) 2007-March 2020.

Methods:
The CDII positively scored four pro-inflammatory foods (processed meats, eggs, organ meats, and sugar-sweetened beverages) and negatively scored four anti-inflammatory foods (dark yellow vegetables, coffee, low-fat dairy products, and sweets and desserts). Multivariable logistic regression was performed to determine the association between CDII (per standard deviation (SD) higher and quartiles) and CKD prevalence (reduced estimated glomerular filtration rate of ≤60 mL/min/1.73 m2 or presence of albuminuria of ≥30 mg/g) in 10,794 participants (≥18 years of age).

Results:
Those in the highest quartile of CDII had a lower dietary intake of protein, fiber, and micronutrients (β-carotene, α-tocopherol, vitamin C, folate), but a higher total fat and dietary cholesterol compared to those in the lowest quartile of CDII. When adjusting for sociodemographic characteristics and health behaviors, per SD unit higher in CDII had a 12% greater odds of CKD [odds ratio (OR), 1.12; 95% confidence interval (CI): 1.01, 1.23]. Those with the highest vs. lowest quartile of CDII had a 53% greater odds of CKD (OR: 1.53, 95% CI: 1.14, 2.05, P for trend=0.02). This association remained significant after adjusting for clinical characteristics.

Conclusion:
Diets with greater inflammatory potential were associated with prevalent CKD. Our study provides support for reducing consumption of pro-inflammatory diets for the prevention of CKD and suggests that the CDII could be used to assess dietary inflammation.

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