McFarlane Catherine, Krishnasamy Rathika, Stanton Tony, Savill Emma, Snelson Matthew, Mihala Gabor, Morrison Mark, Johnson David W, Campbell Katrina L
School of Medicine, University of Queensland, Brisbane, Queensland, Australia; Sunshine Coast University Hospital, Birtinya, Queensland, Australia.
Sunshine Coast University Hospital, Birtinya, Queensland, Australia; Australasian Kidney Trials Network, University of Queensland, Brisbane, Queensland, Australia.
J Ren Nutr. 2022 Sep;32(5):542-551. doi: 10.1053/j.jrn.2021.10.003. Epub 2021 Nov 12.
This study aims to explore the associations between diet quality, uraemic toxins, and gastrointestinal microbiota in the chronic kidney disease (CKD) population.
This is a baseline cross-sectional study of adults with CKD participating in a randomized controlled trial of prebiotic and probiotic supplementation. Dietary intake was measured using a seven-day diet history method, administered by a specialist dietitian. Diet quality was assessed using plant-based diet index (PDI) (overall PDI, healthy PDI, and unhealthy PDI), food group analysis, protein intake, fiber intake, and dietary protein-to-fiber ratio. Serum uraemic toxins (free and total; indoxyl sulfate and p-cresyl sulfate) were determined by ultraperformance liquid chromatography. Gastrointestinal microbiota richness, diversity, composition, and functional capacity were analyzed via metagenomic sequencing.
Sixty-eight adults [median age: 70 (interquartile range: 58-75) years, 66% male] with an estimated glomerular filtration rate of 34 ± 11 mL/min/1.73 m were included, with 40 participants completing the optional fecal substudy. Dietary fiber intake was associated with lower levels of total indoxyl sulfate, whereas the healthy plant-based diet index was associated with lower levels of free p-cresyl sulfate. A higher protein-to-fiber ratio was associated with an increased relative abundance of unclassified members of order Oscillospirales. Intake of vegetables and whole grains was correlated with Subdoligranulum formicile, whereas an unclassified Prevotella species was correlated with potatoes and food items considered discretionary, including sweet drinks, sweet desserts, and animal fats.
Diet quality may influence uraemic toxin generation and gut microbiota diversity, composition, and function in adults with CKD. Well-designed dietary intervention studies targeting the production of uraemic toxins and exploring the impact on gut microbiome are warranted in the CKD population.
本研究旨在探讨慢性肾脏病（CKD）人群的饮食质量、尿毒症毒素和胃肠道微生物群之间的关联。
这是一项针对参与益生元和益生菌补充剂随机对照试验的成年CKD患者的基线横断面研究。饮食摄入量采用由专业营养师管理的7天饮食史方法进行测量。饮食质量通过植物性饮食指数（PDI）（总体PDI、健康PDI和不健康PDI）、食物组分析、蛋白质摄入量、纤维摄入量以及饮食蛋白质与纤维比例进行评估。血清尿毒症毒素（游离和总；硫酸吲哚酚和对甲酚硫酸盐）通过超高效液相色谱法测定。通过宏基因组测序分析胃肠道微生物群的丰富度、多样性、组成和功能能力。
纳入了68名估计肾小球滤过率为34±11 mL/min/1.73 m²的成年人[中位年龄：70（四分位间距：58 - 75）岁，66%为男性]，其中40名参与者完成了可选的粪便子研究。膳食纤维摄入量与较低的总硫酸吲哚酚水平相关，而健康的植物性饮食指数与较低的游离对甲酚硫酸盐水平相关。较高的蛋白质与纤维比例与未分类的颤螺菌目成员相对丰度增加相关。蔬菜和全谷物的摄入量与微小双歧杆菌相关，而未分类的普雷沃氏菌属物种与土豆以及包括甜饮料、甜点心和动物脂肪在内的可自由支配食物相关。
饮食质量可能会影响CKD成年人的尿毒症毒素生成以及肠道微生物群的多样性、组成和功能。针对CKD人群，开展旨在减少尿毒症毒素产生并探索对肠道微生物组影响的精心设计的饮食干预研究很有必要。
