Urinary 8-oxo-7,8-dihydroguanosine as a potential biomarker for the prognosis of acute poisoning patients in the emergency Intensive-care unit: a prospective observational study

Acute poisoning remains a significant cause of admission to the emergency intensive-care unit (EICU). Despite a reduced mortality rate, attention is increasingly focusing on the impact of post-intensive-care syndrome (PICS) on readmission. Due to the significant role of oxidative stress (OS) in the pathological mechanisms of poisoning, 8-oxo-7,8-dihydroguanosine (8-oxoGuo) and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGuo) may hold great potential as biomarkers for OS biomarkers to evaluate the severity and prognosis of poisoning. Therefore, we investigated the longitudinal changes of urinary 8-oxoGuo levels during hospitalization in poisoned patients, their association with organ failure, and their predictive value for 30-day readmission risk. In total, 43 poisoning patients were enrolled from the EICU of the First Affiliated Hospital of Wenzhou Medical University between July 2021 and November 2022. The 30-day readmission rate was 18.6%. Group-based trajectory modeling (GBTM) was used to explore the potential trajectories of urinary OS markers and organ failure scores during hospitalization. Spearman's correlation analysis revealed a significant association between a high trajectory of 8-oxoGuo/creatinine (Cr) and the increased severity of overall organ failure, as well as respiratory and coagulation dysfunctions. Binary logistic regression analysis indicated that a high 8-oxoGuo/Cr trajectory, high respiratory failure score trajectory, and 8-oxoGuo/Cr values at three key points in disease progression (including admission, transfer from EICU, and discharge), along with 8-oxodGuo/Cr levels at admission, were all risk factors for 30-day readmission. The 8-oxoGuo/Cr value at discharge exhibited the best predictive performance. The urinary 8-oxoGuo/Cr ratio may serve as a potential biomarker for prognostic evaluations in patients with poisoning.