Acute kidney injury (AKI), a common complication of cardiac surgery during hospitalization, is linked to increased and prolonged risk of death in heart attack patients who have been discharged from the hospital, according to a study published in Archives of Internal Medicine by Yale School of Medicine researchers.
Led by Chirag Parikh, M.D., associate professor in the Department of Internal Medicine at Yale School of Medicine, the study examined the relationship between AKI and long-term mortality risk in 147,000 elderly patients enrolled in the Cooperative Cardiovascular Project.
"We found that among myocardial infarction patients, there was an association with increased and long-term risk of death for surgery patients who made it out of the hospital," said Parikh. "The risk of death did not appreciably dissipate over time, and was still considerable for those who survived the first three years of follow-up."
The research team graded the relationship between AKI and long-term risk of death. Those with mild, moderate and severe AKI had a 15, 23 and 33 percent increased risk of death respectively after accounting for other known risk factors. For all severities of AKI, there was a consistent link to increased long-term risk of death. AKI was also stronger than other long-term mortality predictors such as diabetes, heart failure, lung disease and chronic kidney disease.
Parikh said that clinicians commonly view AKI as a reversible syndrome and that patients with AKI may benefit from a long-term outpatient follow-up after discharge.
"Future efforts should be undertaken to understand the biology of this relationship between AKI and mortality, and efforts to prevent and treat AKI should be continued," said Parikh.
Other authors on the study include Steven G. Coca, Yongfei Wong, Frederick Masoudi and Harlan Krumholz, M.D.
Citation: Archives of Internal Medicine Vol. 168, 9 (May 12, 2008)