Malnutrition Linked to Increased Risk of Postoperative Acute Kidney Injury

Strategic Insights -

Research conducted at Nara Medical University has found a significant association between malnutrition and the risk of postoperative acute kidney injury (AKI) in noncardiac surgery patients. The study, which analyzed data from patients who underwent noncardiac surgery under general anesthesia between 2007 and 2011, revealed that preoperative malnutrition was a significant predictor of postoperative AKI.

Key Takeaways:

  • The geriatric nutritional risk index (GNRI) is a simple indicator of malnutrition, and the study found that a low GNRI score was associated with a higher risk of postoperative AKI.
  • Adults who underwent noncardiac surgery under general anesthesia were included in the study, and obstetric or urologic surgery, missing serum creatinine, and baseline estimated glomerular filtration rate were excluded from the analysis.
  • The study concluded that improvement of preoperative malnutrition may reduce postoperative AKI.
  • Researchers found that patients with a higher geriatric nutritional risk index score had a lower risk of developing postoperative AKI.
  • The study suggests that preoperative nutritional assessment and improvement of malnutrition may be a valuable strategy to reduce the risk of postoperative AKI.
  • Kashihara, Japan-based researchers used a retrospective cohort study design and analyzed data from 2007 to 2011.
  • The study's authors include Miho Murashima, Masatoshi Nishimoto, Maiko Kokubu, Masaru Matsui, Masahiro Eriguchi, Ken-Ichi Samejima, Yasuhiro Akai, and Kazuhiko Tsuruya.

Statistics:

  • 101 patients were included in the study.
  • The study found that 23.8% of patients developed postoperative AKI.
  • The geriatric nutritional risk index (GNRI) score was a significant predictor of postoperative AKI (p=0.001).
  • Patients with a lower GNRI score had a higher risk of postoperative AKI (p<0.001).

Sources:

  • Preoperative Geriatric Nutritional Risk Index Score as a Novel Predictor of Postoperative Acute Kidney Injury in Noncardiac Surgery: The NARA-AKI Cohort Study. Kidney Medicine, 2025;7(10):101090.
  • World Disease Weekly, October 21, 2025; p 20.