Dados do Trabalho

Título

Association of elevated urea-to-creatinine ratio and clinical outcomes: a retrospective cohort

Objetivo

To evaluate the association between urea/creatinine(U/Cr) ratio and outcomes in critically ill patients.

Métodos

Retrospective cohort of patients admitted to a medical ICU from 2017 to 2023. We divided the patients in three groups based on the presence of AKI, presence of CKD without AKI, or absence of both at ICU admission. A cubic spline model was used to evaluate the relationship between U/Cr ratio and outcomes. The U/Cr ratio was also dichotomized with the cuff-off value of 40 and its association with hospital mortality and need for renal replacement therapy(RRT) were assessed through logistic regression adjusted for SAPS3 and mFI.

Resultados

A total of 2046 patients were included, 787 with AKI criteria, 102 with CKD and 1175 without AKI or CKD at admission. The mean age of patients was 54.2years, mostly male(54.9%) with a mean SAPS3 of 55.1. Approximately thirty-five percent of patients were diagnosed with sepsis or gastrointestinal bleeding. A non-linear relationship was observed regarding urea-to-creatinine ratio and mortality in all groups except for the AKI patients. A higher U/Cr ratio was associated with mortality in an unadjusted analysis in the AKI(OR 1.37, IC95%1.02-1.84,p=0.03) and no AKI/no CKD(OR 1.92, IC95%1.45-2.54,p<0.001) subgroups, although it did not persist in the adjusted analysis(AKI= OR 1.23, IC95%0.87-1.73,p=0.23 and no AKI/no CKD= OR 1.36, IC95%0.98-1.89,p=0.06). Patients with AKI and higher U/Cr ratio had a lower RRT requirement(ORadj=0.64,IC65%0.45-0.9,p=0.01) and the no AKI/no CKD subgroup presented a higher RRT requirement in this context(ORadj=2.86,IC95%1.01-8.11,p=0.04).

Conclusão

High urea/creatinine ratios are more likely explained by other factors than pre-renal fluid-responsive AKI.