Journal Article

Higher plasma cystatin C is associated with mortality after acute respiratory distress syndrome: findings from a Fluid and Catheter Treatment Trial (FACTT) substudy

Shlipak, Michael G., Liu, Kathleen D., Matthay, Michael A., Hendrickson, Carolyn M., Kwong, Yuenting D., Belzer, Annika G.

2020

Overview

Background Cystatin C is a well-validated marker of glomerular filtration rate in chronic kidney disease. Higher plasma concentrations of cystatin C are associated with worse clinical outcomes in heterogenous populations of critically ill patients and may be superior to creatinine in identifying kidney injury in critically ill patients. We hypothesized that elevated levels of plasma cystatin C in patients with acute respiratory distress syndrome (ARDS) would be associated with mortality risk. Methods In a retrospective study, cystatin C was measured by nephelometry on plasma obtained at enrollment from 919 patients in the Fluid and Catheter Treatment Trial. Multivariable logistic regression was performed testing the association between quartiles of cystatin C and 60-day mortality. Analyses were stratified by acute kidney injury (AKI) status identified in the first 7 days after enrollment by Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Results Cystatin C was significantly higher among those patients who died compared to those who survived to 60 days [1.2 (0.9–1.9) mg/L vs. 0.8 (0.6–1.2) mg/L, p  < 0.001]. Compared to the lower three quartiles, subjects in the highest quartile of cystatin C had a significantly higher odds of death at 60 days [OR 1.8 (1.2–2.6), p  = 0.003 in adjusted analyses]; the odds of death incrementally rose in higher cystatin C quartiles compared to the lowest quartile (OR 1.1, 1.8, and 2.5). In adjusted analyses stratified by AKI status, compared to subjects in the lower three quartiles, subjects in the highest quartile of cystatin C with AKI had a significantly higher odds of death at 60 days both in participants with AKI [OR 1.6 (1.0–2.4), p  = 0.048] and those without AKI [OR 2.4 (1.2–5.0), p  = 0.017]. In adjusted analyses, there was no significant association between sex-stratified baseline creatinine quartiles and mortality. Conclusions Higher plasma levels of cystatin C on enrollment were strongly associated with mortality at 60 days in patients with ARDS with and without AKI identified by creatinine-based definitions. Compared to creatinine, cystatin C may be a better biomarker of kidney function in patients with ARDS and therefore identify patients with multiple organ failure at higher risk of death.

• Publisher: BioMed Central,BioMed Central Ltd,Springer Nature B.V,BMC
• Subject: Acute kidney injury (AKI) / Acute respiratory distress syndrome (ARDS) / Adult / Adult respiratory distress syndrome / Aged / Analysis / APACHE / Biomarkers / Biomarkers - analysis / Biomarkers - blood / Catheters / Chronic kidney failure / Clinical trials / Cohort Studies / Correlation of Data / Creatinine / Critical care / Critical Care Medicine / Cystatin C / Cystatin C - adverse effects / Cystatin C - analysis / Cystatin C - blood / Emergency Medicine / Female / Humans / Intensive / Kidney diseases / Logistic Models / Male / Medical research / Medicine / Medicine & Public Health / Middle Aged / Mortality / Patient outcomes / Plasma / Plasma - chemistry / Prospective Studies / Pulmonary arteries / Respiratory distress syndrome / Respiratory Distress Syndrome - drug therapy / Respiratory Distress Syndrome - mortality / Retrospective Studies / Sepsis / Variables