Comparison of Three Diet Quality Indices for Patients with Chronic Kidney Disease

Patients with chronic kidney disease (CKD) have specific dietary needs due to recommended dietary restrictions. However, there is no specific index for evaluating the quality of diet in patients with CKD.   OBJECTIVE: To define and compare three specific diet quality indices in patients with CKD.

Two hundred twenty-one subjects with CKD were selected for this cross-sectional study. The patients' Dietary intake was assessed with a validated food frequency questionnaire. Total protein intake per body weight (TP/BW), animal protein intake per body weight (AP/BW) and animal protein to vegetable protein ratio (AP/VP) were defined as diet quality indices. Renal function was measured by blood urea nitrogen (BUN) and serum creatinine (Cr).

Patients in the highest tertile of TP/BW and tertile of AP/BW consumed more amounts of nutrients which should be limited in CKD (i.e., sodium, potassium and phosphorus). Subjects in the last tertile of AP/BW had higher BUN and Cr. A marginally significant increased risk of higher stage of CKD across the tertiles of AP/BW was observed after adjusting for potential confounders (OR = 2.20, 95% CI: 1.06, 4.56; P = 0.08).

The results showed that AP/BW is a good diet quality index and is marginally associated with being in higher stages of CKD.