Acute Kidney injury (AKI) Outcome, a Predictor of Long-term Major Adverse Cardiovascular Events (MACE)

AUTHORS:  

Bolanle A. Omotoso, Emaad M. Abdel-Rahman, Jennie Z. Ma, Rasheed A. Balogun

Address: Division of Nephrology, University of Virginia, Charlottesville, VA, 22908 

BACKGROUND

The incidence of AKI in hospitalized patients is increasing. Many of these patients survive the immediate acute AKI period and may be prone to develop long term outcomes of AKI. This study aims to determine if complete recovery of renal function after AKI is associated with lower risk of MACE.

METHODS

The study is a cohort of adults admitted into the University Of Virginia Medical Center between January 1, 2002 and December 31, 2012 and developed AKI while on admission. They were followed up through Dec 31 2013. AKI is defined as an increase in serum creatinine (Scr) by ?0.3mg/dl from the baseline and or requirement for acute dialysis during the index hospitalization.  Complete recovery is defined as a return of serum creatinine level to less than 1.25 times the baseline value.

OUTCOME MEASUREMENT

MACE is defined as subsequent admission for Myocardial Infarction (MI), Transient Ischemic Attack (TIA), stroke and heart failure using ICD 9 codes. The date of MACE is defined as the date of the first qualifying event.

RESULTS

Overall, 19.57% of the participants n=24,631 had AKI,(10.96% had AKI, 8.6 had AKI on a background CKD). 11538 survived 90 days of AKI and available for analysis. Mean age and baseline eGFR were 56.79 ±15.79years and 87.48 ± 17.34 mls/min/1.73m? respectively. Of the 9,637 survivors of AKI in whom recovery could be assessed, 7170 (74.4%) recovered to within 25% of their baseline serum Creatinine.

Major adverse cardiovascular event occurred in 27.28% of patients over a median follow up period of 399 days. Predictors of MACE following AKI identified were increasing age, male gender, African Americans, smoking, and prior history of hypertension, recovery of renal function ,baseline eGFR and high charlson co morbidity score index. Complete renal recovery and higher baseline eGFR were associated with lower risk of MACE (Adjusted harzard ratios 95% CI, 0.774(0.713, 0.842) and 0.990(0.988, 0.993) respectively.

CONCLUSION: 

Complete renal recovery after an episode of AKI in patients with normal baseline Kidney function is associated with a lower risk of long term major adverse cardiovascular events when compared with those who did not fully recover.