Study Identifies D-Dimer Dynamics as Independent Predictor of AKI Patient Survival

The retrospective study evaluated medical records of AKI patients admitted to Tongji Hospital between July 2012 and April 2024. Eligible participants included those who had undergone at least three D-dimer tests within 30 days following the onset of AKI. The aim was to identify distinct patterns in D-dimer trajectories and explore their link with in-hospital mortality.

To achieve this, the researchers employed latent class trajectory models (LCTMs), which enabled the classification of patients into subgroups based on the evolution of their D-dimer levels. After analyzing multiple models using statistical indices such as the Akaike Information Criterion and Bayesian Information Criterion, a two-class model emerged as the best fit.

The study led to the following findings:

• The study identified two D-dimer trajectory patterns: an early spike followed by a gradual decline and a consistently low level.
• Patients were categorized into the "high-peak decline group" and the "sustained low-level group."
• Those in the high-peak decline group had a significantly higher risk of in-hospital mortality.
• Logistic regression revealed over twice the odds of in-hospital death in the high-peak group compared to the low-level group (OR 2.27).
• Kaplan-Meier survival curves showed reduced survival rates in the high-peak decline group.
• Subgroup analyses confirmed the higher mortality risk in the high-peak group across age, gender, chronic kidney disease, cancer, surgery, myocardial infarction, and cerebral infarction.
• No significant interactions were found in subgroup analyses, indicating that the mortality risk linked to D-dimer trajectories was independent of other clinical variables.

Despite valuable findings, the study's limitations include its single-center, retrospective design, which limits generalizability. Missing inflammatory markers and severity scores restrict the assessment of systemic inflammation. AKI diagnosis relied only on serum creatinine, possibly underestimating mild cases. Additionally, the absence of post-discharge follow-up hinders the evaluation of long-term patient outcomes.

There was no clear link between D-dimer trajectories and pulmonary embolism, possibly due to the small number of such cases in the dataset.

The authors recommend that future research adopt multicenter, prospective designs with comprehensive data collection, including inflammatory and coagulation markers, to enhance clinical relevance.

The authors concluded, "The study highlights that monitoring the dynamic changes in D-dimer levels can serve as a valuable tool for predicting in-hospital mortality among AKI patients. Given its accessibility and cost-effectiveness, D-dimer may support timely prognosis evaluation and personalized treatment strategies in clinical practice."

Reference:

Rao, L., Sun, J., Zhao, X., Ge, S., & Li, N. (2025). Association between D-dimer and in-hospital mortality risk in Acute Kidney Injury based on latent class dynamic trajectory. Frontiers in Medicine, 12, 1554213. https://doi.org/10.3389/fmed.2025.1554213