April 30, 2009Clinical Journal of the American Society of Nephrology396 citationsOpen Access
Nonrecovery of Kidney Function and Death after Acute on Chronic Renal Failure
Key Result
An episode of superimposed dialysis-requiring acute renal failure in patients with chronic kidney disease increased the long-term risk for death or end-stage renal disease by 30% (HR 1.30).
Study Design
Type
Cohort (n=39,805)
Multicenter
Yes
Structured PICO
Does superimposed acute renal failure requiring dialysis increase the risk of death or ESRD in hospitalized patients with chronic kidney disease?
P
Population
39,805 hospitalized patients with chronic kidney disease (prehospitalization eGFR <45 ml/min per 1.73 m2) in an integrated health care delivery system in northern California
I
Intervention
Superimposed acute renal failure (ARF) requiring acute dialysis
C
Comparator
Patients with chronic kidney disease who did not experience superimposed acute renal failure
O
Outcome
Long-term risk for death or end-stage renal disease (ESRD)hard clinical
In patients with chronic kidney disease, an episode of superimposed acute renal failure requiring dialysis is an independent risk factor for long-term death or progression to end-stage renal disease.
Main Result
Effect estimate: HR 1.30 (95% CI 1.04-1.64)
Limitations
- MDRD equation may misclassify certain patients with low eGFR
- May have failed to identify individuals who developed ESRD but were not initiated on dialysis
- Not able to define precisely the cause of ARF
- Did not have information regarding details of treatment such as dialysis dosage
- Potential residual confounding by severity of diabetes and other comorbidities
- Results may not be completely generalizable to the uninsured or to people in other health care settings
Abstract
BACKGROUND AND OBJECTIVES: Relatively little is known about clinical outcomes, especially long-term outcomes, among patients who have chronic kidney disease (CKD) and experience superimposed acute renal failure (ARF; acute on chronic renal failure). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We tracked 39,805 members of an integrated health care delivery system in northern California who were hospitalized during 1996 through 2003 and had prehospitalization estimated GFR (eGFR) or =50% and receipt of acute dialysis. RESULTS: Overall, 26% of CKD patients who suffered superimposed ARF died during the index hospitalization. There was a high risk for developing ESRD within 30 d of hospital discharge that varied with preadmission renal function, being 42% among hospital survivors with baseline eGFR 30-44 ml/min per 1.73 m(2) and 63% among hospital survivors with baseline eGFR 15-29 ml/min per 1.73 m(2). Compared with patients who had CKD and did not experience superimposed ARF, those who did had a 30% higher long-term risk for death or ESRD. CONCLUSIONS: In a large, community-based cohort of patients with CKD, an episode of superimposed dialysis-requiring ARF was associated with very high risk for nonrecovery of renal function. Dialysis-requiring ARF also seemed to be an independent risk factor for long-term risk for death or ESRD.