Kidney Week

Abstract: PO2362

Tubular Secretion Markers and Declining Kidney Function in the SPRINT Trial

Session Information

• Reassessing Race in Predicting Progression
  November 04, 2021 | Location: On-Demand, Virtual Only
  Abstract Time: 10:00 AM - 12:00 PM

Category: CKD (Non-Dialysis)

• 2101 CKD (Non-Dialysis): Epidemiology, Risk Factors, and Prevention

Authors

• Garimella, Pranav S., University of California San Diego, La Jolla, California, United States

Pranav S. Garimella,

• Ascher, Simon, University of California Davis, Davis, California, United States

Simon Ascher,

• Katz, Ronit, University of Washington, Seattle, Washington, United States

Ronit Katz,

• Bullen, Alexander, University of California San Diego, La Jolla, California, United States

Alexander Bullen,

• Estrella, Michelle M., University of California San Francisco, San Francisco, California, United States

Michelle M. Estrella,

• Malhotra, Rakesh, University of California San Diego, La Jolla, California, United States

Rakesh Malhotra,

• Jotwani, Vasantha, University of California San Francisco, San Francisco, California, United States

Vasantha Jotwani,

• Hallan, Stein I., UiT Norges arktiske universitet, Tromso, Troms, Norway

Stein I. Hallan,

• Scherzer, Rebecca, University of California San Francisco, San Francisco, California, United States

Rebecca Scherzer,

• Shlipak, Michael, University of California San Francisco, San Francisco, California, United States

Michael Shlipak,

• Ix, Joachim H., University of California San Diego, La Jolla, California, United States

Joachim H. Ix,

Background

Tubular secretion is an important aspect of kidney function that is not routinely assessed. Emerging evidence suggests that impaired secretion may be associated with increased risk of kidney function decline.

Methods

In a cohort of 2089 SPRINT trial participants with baseline eGFR < 60ml/min/1.73m², we measured a panel of 10 solutes in serum and urine, that were previously identified as markers of tubular secretion. We created a standardized composite secretory score using the urine to plasma ratios of all 10 biomarkers. We evaluated associations of this composite score with annual % eGFR decline and progression of CKD (>30% loss of eGFR) using multivariable linear regression and Cox regression models, respectively.

Results

Mean participant age at baseline was 73 years, 41% were female, and 24% identified as Black. The mean eGFR varied by secretion score quartile: from 39 ml/min/1.73m² in the lowest quartile to 51 ml/min/1.73m² in the highest quartile. In multivariable adjusted analyses, eGFR declined faster for participants in the lower two quartiles of secretory score compared with participants in the higher two quartiles (Figure). There was no significant interaction between secretion score and randomized treatment assignment for the outcome of eGFR decline. In unadjusted models, each 1-SD higher secretion score was associated with a lower risk of CKD progression (HR 0.49; 95% CI, 0.35, 0.70), but this association was attenuated by multivariable adjustment (HR 0.75, 95% CI 0.53, 1.07).

Conclusion

Impaired secretory function as measured by a panel of endogenous markers is associated with faster decline in eGFR among persons with CKD.

Funding

• NIDDK Support