Foods contributing to nutrients intake and assessment of nutritional status in pre-dialysis patients: a cross-sectional study.

BACKGROUND: For chronic kidney disease (CKD) patients, management of nutritional status is critical for delaying progression to end-stage renal disease. The purpose of this study is to provide the basis for personalized nutritional intervention in pre-dialysis patients by comparing the foods contributing to nutrients intake, nutritional status and potential dietary inflammation of CKD patients according to the diabetes mellitus (DM) comorbidity and CKD stage. METHODS: Two hundred fifty-six outpatients referred to the Department of Nephrology at SNUH from Feb 2016 to Jan 2017 were included. Subjects on dialysis and those who had undergone kidney transplantation were excluded. Bioelectrical impedance analysis (BIA), subjective global assessment (SGA), dietary intake, and biochemical parameters were collected. Subjects were classified into 4 groups according to DM comorbidity (DM or Non-DM) and CKD stage (Early or Late) by kidney function. Two-way analysis of variance and multinomial logistic regression analysis were performed for statistical analysis. RESULTS: Total number of malnourished patients was 31 (12.1%), and all of them were moderately malnourished according to SGA. The body mass index (BMI) of the DM-CKD group was significantly higher than the Non-DM-CKD group. The contribution of whole grains and legumes to protein intake in the DM-CKD group was greater than that in the Non-DM-CKD group. The DM- Early-CKD group consumed more whole grains and legumes compared with the Non-DM-Early-CKD group. The subjects in the lowest tertile for protein intake had lower phase angle, SGA score and serum albumin levels than those in the highest tertile. The potential for diet-induced inflammation did not differ among the groups. CONCLUSIONS: Significant differences in intakes of whole grains and legumes between CKD patients with or without DM were observed. Since contribution of whole grains and legumes to phosphorus and potassium intake were significant, advice regarding whole grains and legumes may be needed in DM-CKD patients if phosphorus and potassium intake levels should be controlled. The nutritional status determined by BIA, SGA and serum albumin was found to be different depending on the protein intake. Understanding the characteristics of food sources can provide a basis for individualized nutritional intervention for CKD patients depending on the presence of diabetes.

Vitamin D supplementation partially affects colonic changes in dextran sulfate sodium-induced colitis obese mice but not lean mice.

Inflammatory bowel disease (IBD) often accompanies vitamin D deficiency, and vitamin D supplementation ameliorates IBD symptoms in animal models and humans. Because altered vitamin D metabolism has been reported in obesity, we hypothesized that the effects of vitamin D on the development of IBD would be different between obese and control mice. Five-week-old male C57BL/6N mice were divided into 4 groups and fed a diet differing in fat content (10% or 45%, normal diet [ND] or high-fat diet [HFD]) and vitamin D content (1000 or 10 000 IU/kg of diet, vDC or vDS) for 14 weeks. At week 13, colitis was induced by administration of 2% dextran sodium sulfate for 7 days. Histology score tended to be lower in the HFD-vDS group than HFD-vDC group, but there was no effect of vitamin D on the ND group. Colonic Cldn1 and Cyp27b1 mRNA levels were higher in the HFD-vDS than HFD-vDC group, but these effects of vitamin D were not observed in the ND group. The serum 25-hydroxy vitamin D levels were negatively correlated with the histology score in the HFD group but not in the ND group. Overall, these results suggest that vitamin D supplementation partially prevents the histological damage of the colon in obese mice but not in control mice. This effect might be mediated by increased colonic Cyp27b1 levels, leading to upregulation of local 1,25-dihydroxy vitamin D production.