"Worsening renal function is a warning complication in patients with acute heart failure syndrome,” says Andrew Burger, MD, UC Health cardiologist and co-investigator in the study. "Between 30 and 50 percent of patients hospitalized for acute heart failure have further worsening of renal function during hospitalization, but there is very little data available about the clinical implication of transient versus persistent worsening of renal function in this setting.
Creatinine is a product of creatine phosphate, or energy phosphate, in the muscle and brain. It is filtered out of the blood by the kidneys. If the filtering of the kidney is deficient, blood levels rise, and creatinine levels in blood and urine are used to calculate the kidney’s function.
In this study, worsening renal function was defined as persistent when serum creatinine remained greater than 0.5 mg/dL (milligrams per deciliter) above baseline throughout to day 30 and transient when the elevated creatinine levels decreased to less than 0.5 mg/dL above baseline within the 30-day period.
"Worsening renal function occurred in 115 patients—39 of those cases were considered transient,” says Burger.
He adds that researchers saw death in 17.3 percent of patients without worsening renal function, 20.5 percent of patients with transient worsening dysfunction and 46.1 percent of patients with persistent renal dysfunction.
"The patients with no change in renal function and transient dysfunction have the same outcome, while patients with persistent renal dysfunction are more like to die,” Burger says. "Chronic heart failure encompasses an important interaction between the heart and the kidneys, and renal dysfunction often accompanies heart failure.
"These findings give cardiologists some insight into the degree of renal dysfunction and its association with mortality in both stable and acute heart failure syndrome. Hopefully, these results will lead to further studies that may help in determining better interventions and outcomes for patients with acute heart failure.”
Scios Inc., a subsidiary of Johnson & Johnson, sponsored the study. Burger cites no conflict of interest.