Twenty-four-hour urine phosphorus as a biomarker of dietary phosphorus intake and absorption in CKD: A secondary analysis from a controlled diet balance study
Clinical Journal of the American Society of Nephrology Jul 01, 2018
Stremke ER, et al. - Researchers undertook this secondary analysis to investigate whether 24-hour urine phosphorus is reliable and accurate as a biomarker of phosphorus intake and absorption in moderate CKD. The study included eight patients with moderate CKD on a tightly controlled dietary intake. In these subjects, highly variable 24-hour urine phosphorus was detected, which was not associated with dietary phosphorus intake or absorption, rather it was found to have an inverse association with phosphorus retention.
Methods
- In 2-week balance studies, participants were patients with stage 3–4 CKD on tightly controlled phosphorus and calcium intakes.
- Researchers analyzed thirteen 24-hour urine collections per patient in order to assess variability and reliability of 24-hour urine phosphorus and phosphorus-to-creatinine ratio.
- They used a published equation to determine the accuracy of 24-hour urine phosphorus to predict phosphorus intake.
- They determined the associations of 24-hour urine phosphorus with phosphorus intake, net absorption, and retention.
Results
- Within and among subjects, they detected wide day-to-day variation in 24-hour urine phosphorus (coefficient of variation of 30% and 37%, respectively).
- Findings showed two 24-hour urine measures were required to achieve ≥75% reliability.
- Up to 98% underestimation in some patients and overestimation up to 79% in others was found to be resulted from the estimation of dietary phosphorus intake from a single 24-hour urine.
- A negative correlation of 24-hour urine phosphorus with whole-body retention but no relation to net absorption was observed .
Only Doctors with an M3 India account can read this article. Sign up for free or login with your existing account.
4 reasons why Doctors love M3 India
-
Exclusive Write-ups & Webinars by KOLs
-
Daily Quiz by specialty
-
Paid Market Research Surveys
-
Case discussions, News & Journals' summaries