Relationship between dietary phosphorus intake and nutritional status and calcium and phosphorus metabolism in patients with chronic kidney disease / 中华肾脏病杂志

ABSTRACT

Objective@#To evaluate the dietary phosphorus intake of non-dialysis patients with chronic kidney disease (CKD) 3-5 stage, and to explore the relationship between dietary phosphorus intake, nutritional status, and calcium and phosphorus metabolism.@*Methods@#A cross-sectional study was conducted. Non-dialysis patients of CKD 3-5 stage in Huashan Hospital outpatient clinic were selected. Three-day dietary diaries, anthropometric indicators, subjective global assessment (SGA) scores, blood and 24-hour urine biochemical indicators were collected. According to the median dietary phosphorus intake (873 mg/d), the patients were divided into high phosphorus intake group (≥ 873 mg/d) and low phosphorus intake group (<873 mg/d). The differences of characteristics, anthropometric indicators, SGA scores, blood and urine biochemical indicators between the two groups were compared. Multivariate linear regression analysis was used to analyze the correlation between dietary phosphorus intake and different kinds of food intake.@*Results@#A total of 118 patients were enrolled. The daily energy intake was (25.48±4.45) kcal/kg, protein intake was (0.88±0.22) g/kg and phosphorus intake was(862.85±233.02) mg/d. There were no significant differences in body mass index and SGA scores between high phosphorus intake group and low phosphorus intake group. The waist circumference, hip circumference, waist-hip ratio and leg circumference of male patients in high phosphorus intake group were higher than those in low phosphorus intake group (all P<0.05). There were no significant differences in anthropometric indicators between the two groups of female patients. The serum levels of intact parathyroid hormone (iPTH), sodium, triglyceride, blood RBC count, alanine aminotransferase, 24-hour urine urea nitrogen, 24-hour urine creatinine and 24-hour urine phosphate in the high phosphorus intake group were higher than those in the low phosphorus intake group (all P<0.05). Multivariate regression analysis showed that pork and chicken contributed the most to dietary phosphorus intake, followed by fish and dairy.@*Conclusions@#The daily dietary phosphorus intake of non-dialysis of CKD 3-5 stage patients is slightly higher than the recommended intake. The increase of dietary phosphorus intake may lead to the increase of serum iPTH and sodium levels. Proper control of dietary phosphorus intake will not impair the nutritional status of CKD patients.