Lower pre-dialysis creatinine ups death risk in acute kidney injury

Among patients with acute kidney injury requiring dialysis therapy (AKI-D), lower levels of pre-dialysis creatinine may be a useful predictor of mortality risk, a recent study has found.

Researchers conducted a retrospective observational cohort study including 1,600 patients (mean age 62.5 years, 58.7 percent men), in whom the 30-day mortality rate was found to be 34.2 percent.

Using a median creatinine value of 4 mg/dL, participants were divided into the high-creatinine (n=743) and low-creatinine (n=857) groups. Crude overall mortality rate was significantly higher in the former (44.9 percent vs 21.9 percent; p<0.001).

Multivariate logistic regression analysis confirmed this association and found that patients belonging to the low-creatinine group saw a nearly 80-percent higher 30-day mortality risk than their high-creatinine counterparts (odds ratio, 1.77, 95 percent confidence interval, 1.29–2.42; p<0.001).

Similarly, those with low creatinine had significantly higher overall sepsis-related organ failure assessment (SOFA) and nonrenal SOFA scores than patients in the high-creatinine group (p<0.0001 for both), which could have contributed to the worse overall survival.

Sensitivity analyses according to body mass index and fluid overloading did not meaningfully impact the principal findings, though a fluid overloaded status further aggravated death risk in patients in the low-creatinine group.

“In patients with AKI-D, the low-creatinine group had a significantly higher risk of mortality compared with that of the high-creatinine group. Moreover, the mortality rate was substantially higher in patients with lower predialysis creatinine with concomitant elevation of fluid overload status,” the researchers said.