Abstract: FR-PO111

Low Serum Bicarbonate Levels at Admission Predict the Development of Hospital Acquired AKI: A Retrospective Cohort Study

Session Information

Category: Acute Kidney Injury

  • 003 AKI: Clinical and Translational

Authors

  • Lee, Soojin, Seoul national university hospital, Seoul, Korea (the Republic of)
  • Lim, Sung Yoon, Korea University Medical Center, Sungbuk-Gu, SEoul, Korea (the Republic of)
  • Lee, Anna, SNUBH, Gyeonggi-do, Korea (the Democratic People's Republic of)
  • Chin, Ho Jun, Seoul National University Bundang Hospital, Seong nam, Korea (the Republic of)
  • Na, Ki Young, Seoul National University Bundang Hospital, Seong nam, Korea (the Republic of)
  • Kim, Sejoong, Seoul National University Bundang Hospital, Seong nam, Korea (the Republic of)
Background

Acute kidney injury(AKI) is a common complication and is strongly related to increase in mortality. Low serum bicarbonate levels are associated with adverse renal outcomes and increased mortality in patients with chronic kidney injury. Nevertheless, it is unknown whether lower than normal serum bicarbonate levels can predict the development of AKI in hospitalized patients. The purpose of the study was to determine whether serum bicarbonate levels at admission could be a predictor for the AKI development and mortality in hospitalized patients.

Methods

17706 adult patients who were admitted to Seoul National University, Bundang Hospital from January 2013 to December 2013 were enrolled, retrospectively. The patients were divided into 3 groups based on serum bicarbonate levels on the first measurement of their admission. The group 1 presented below normal levels, (<23 mEq/L); group 2 presented normal levels, (23 to 27 mEq/L); and group 3 presented elevated levels, (>27 mEq/L). AKI was defined as an increase in the serum creatinine level by ≥ 0.3 mg/dL or ≥ 1.5 times of the baseline value during the hospital stay.

Results

During the median 6.0 days of hospital stay, the incidence rates of AKI and in-hospital mortality were 5.1% and 0.9%, respectively. The incidence of AKI was higher in group 1 (8.1%) than in group 2 (4.1%) and group 3 (3.6%) (P < 0.001). Low serum bicarbonate levels at admission were significantly associated with AKI even after the adjustment for age, sex, hypertension, diabetes mellitus, and estimated glomerular filtration rate (adjusted odds ratio [OR] 2.181, P < 0.001). In addition, low serum bicarbonate levels also independently predicted in-hospital mortality (adjusted hazard ratio [HR] 1.864, P < 0.001). Pre-existing low bicarbonate levels and subsequent development of AKI increased in-hospital mortality by 15 times, compared to the in-hospital mortality of the patients with normal bicarbonate levels and absence of AKI.

Conclusion

Low serum bicarbonate levels may be associated with the development of AKI and increase in in-hospital-mortality. Clinical trials are needed to clarify the protective role of bicarbonate replacement therapy in preventing further AKI development.