Dietary inflammatory index and its association with renal function and progression of chronic kidney disease.

BACKGROUND: While evidence exists for an association between the dietary inflammatory index (DII) and cardiovascular diseases, the relation between DII and chronic kidney disease (CKD) is not known.

OBJECTIVE: To examine the association between DII, renal function and progression of CKD.

METHODS: In this cross-sectional study, dietary data from 221 subjects with diagnosed CKD were collected using a validated food frequency questionnaire. DII was calculated based on overall inflammatory effect scores. Renal function was measured by blood urea nitrogen (BUN) and serum creatinine (Cr) level as well as estimated glomerular filtration rate (eGFR).

RESULTS: Patients in the first tertile of DII consumed higher quantities of vegetables, fruits, dairy, calcium, potassium and phosphorus and lower amounts of grains (P < 0.01 for all). We did not detect any significant trend for BUN, Cr and eGFR across tertiles of DII in crude and two adjusted models. In a fully adjusted model, an increased risk of being in the higher stage of CKD was found among those in the top tertiles of DII (odds ratio: 2.12; 95% CI: 1.05, 4.26; P for trend = 0.03).

CONCLUSION: We observed that compliance with a pro-inflammatory diet in patients with CKD may be associated with disease progression.