Predictive Factors Upon Discontinuation of Renal Replacement Therapy for Long‐Term Chronic Dialysis and Death in Acute Kidney Injury Patients

Abstract

The specific timing for discontinuing renal replacement therapy (RRT) in acute kidney injury (AKI) patients is debatable. The predictive abilities of variables at the time of discontinuation of RRT for the long-term prognoses of patients have not been explored. This study aimed to explore the prognostic factors upon discontinuation of RRT for long-term chronic dialysis and death of patients with acute RRT-requiring AKI, thus improving decision making regarding the discontinuation of RRT and the follow-up of patients thereafter. A cohort of 302 AKI patients who required acute RRT and remained alive and free of dialysis for at least 30 days after discharge from January 2009 to December 2012 were followed up. The predictive abilities of general characteristics, RRT details, and variables upon discontinuation of RRT for long-term chronic dialysis and all-cause death were evaluated using Cox proportional hazards models. Kaplan-Meier analysis with a log-rank test was used to compare the survival curves between the strata of levels of good predictors upon discontinuation of RRT. After a median follow-up time of 4.1 years, 20 (6.6%) patients initiated chronic dialysis and 56 (18.5%) patients died. A higher CysC level upon discontinuation of RRT (HR 1.520, 95% CI 1.082-2.135; P = 0.016), comorbid chronic kidney disease, and a higher non-renal Charlson comorbidity index (CCI) were independently predictive for chronic dialysis. The hemoglobin level upon discontinuation of RRT was inversely predictive of death (HR 0.986, 95% CI 0.973-0.999; P = 0.035), and comorbid malignancy, the presence of multiple organ dysfunction syndrome, and a higher non-renal CCI also predicted death. Urine output upon discontinuation of RRT was marginally inversely predictive of death (HR 0.997, 95% CI 0.994-1.000; P = 0.056). Patients who discontinued RRT with CysC levels <2.97 mg/L, hemoglobin levels >85 g/L, and urine output >1130 mL/24 h showed significantly higher non-chronic dialysis and survival rates according to a log-rank test. Our study suggested that upon discontinuation of RRT, higher serum CysC levels had the most promising predictive value for long-term chronic dialysis, and lower hemoglobin levels predicted long-term death; lower urine output also marginally predicted long-term death. Based on the remission of the comprehensive condition, lower CysC levels and higher hemoglobin levels and urine output should be considered in the decision to stop RRT. Patients showing worse levels of these indices upon discontinuation of RRT should undergo stricter follow-up and treatment to improve long-term outcomes.

Determining the optimal time for liberation from renal replacement therapy in critically ill patients: a systematic review and meta-analysis (DOnE RRT)

“…Where multiple studies reported on the same variable, the threshold values with optimal predictive accuracy varied, as did the timing of measurement in relation to RRT discontinuation. For cystatin C, two studies measured values prior to RRT discontinuation [29,31], and three measured values following discontinuation [28][29][30] (Table 3). The optimal threshold values ranged from 1.85 to 2.98 mg/L, respectively.…”

“…Kidney biomarkers have shown promise for prognostication in the setting of AKI and have been assessed in several studies evaluating RRT discontinuation and kidney recovery. Cystatin C was the most commonly studied, and though it appears to have a promising discrimination, due to substantial clinical heterogeneity in the timing of measurement and threshold values used in retrieved studies [28][29][30], data could not be pooled and definitive inferences on the accuracy of cystatin C measurement to predict successful RRT discontinuation could not be provided.…”

“…Numerous parameters have been evaluated to help identify patients for whom RRT may be safely discontinued, including traditional biochemical markers of kidney function (creatinine, urea, and estimates of glomerular filtration rate (GFR) [17][18][19][20][21][22][23][24][25][26]), clinical findings such as urine output [21-23, 26, 27], and newer kidney biomarkers including neutrophil gelatinase-associated lipocalin (NGAL) [19,28,29] and serum cystatin C [28][29][30][31]. Despite many criteria being evaluated in the existing literature, the available evidence has yet to be rigorously synthesized.…”

Predictors of successful discontinuation from renal replacement therapy during AKI: A meta‐analysis

“…Acute kidney injury (AKI) is a highly common and multifactorial renal disease, the clinical manifestation of which is acute and sustained decrease of glomerular filtration rate, with an in‐hospital incidence of 0.2–9.6% and accounting for 7–35% of intensive care unit (ICU) patients 1 . Renal replacement therapy (RRT) is the mainstay of therapy for approximately 8–12% of critically ill AKI patients 2 . There have been studies showing that about 10–30% AKI patients requiring RRT will wean RRT successfully at discharge 3–6 .…”

Artificial Organs 2017: A Year in Review

“…Yang et al of the West China Hospital of Sichuan University, Sichuan, People's Republic of China investigated the predictive factors upon discontinuation of renal replacement therapy RRT) for long‐term chronic dialysis and death in AKI patients. Their study suggested that upon discontinuation of RRT, higher serum cystatin C levels had the most promising predictive value for long‐term chronic dialysis, and lower Hb levels predicted long‐term death; lower urine output also marginally predicted long‐term death.…”