CKD Progression after Acute Kidney Injury: A Secondary Analysis of the Standard versus Accelerated Initiation of Renal Replacement Therapy in Acute Kidney Injury Trial.

KEY POINTS

Development or progression of CKD occurred in almost 40% of patients after an episode of severe AKI. Receipt of KRT, regardless of allocation to an accelerated or standard initiation strategy, was associated with development or progression of CKD. This study helps identify a subset of patients at risk of CKD after severe AKI who would benefit from dedicated kidney follow-up after discharge.

BACKGROUND

CKD is a common complication after AKI. We aimed to evaluate whether a KRT initiation strategy had an effect on CKD progression. Secondarily, we aimed to identify factors that influenced the development or progression of CKD after severe AKI.

METHODS

This secondary analysis of the Standard versus Accelerated Initiation of Renal Replacement Therapy in AKI trial included patients with outpatient serum creatinine values available in the year before hospitalization and who were alive at 90 days after randomization. Our main analysis focused on patients who had definitive assessment of kidney function at 90 days after randomization. Predictor markers included patient demographics, comorbidities, markers of acute illness, laboratory values, receipt of KRT, and KRT treatment strategy (accelerated versus standard). The primary outcome was CKD progression, a composite of CKD, defined as new eGFR <60 ml/min per 1.73 m if baseline eGFR was ≥60 ml/min; a decline in eGFR ≥25% if baseline eGFR was <60 ml/min; or KRT dependence at day 90. The association of KRT treatment strategy with CKD progression was assessed in an unadjusted mixed-effect logistic regression model.

RESULTS

Of the 401 surviving patients with a baseline serum creatinine, 39% experienced CKD progression. KRT initiation strategy had no effect on CKD progression (accelerated arm [41%], versus the standard arm [38%], odds ratio, 1.13 [95% confidence interval, 0.75 to 1.72]). Receipt of KRT and aortic surgery were the most potent risks of CKD progression.

CONCLUSIONS

These findings suggest that CKD progression is common after severe AKI. Risk factors of CKD progression included receipt of KRT and aortic surgery, suggesting that these patients should be prioritized for dedicated kidney follow-up after hospital discharge.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

: NCT01557361.