Elevated urea nitrogen to creatinine ratio during hospitalization is associated with 90-day poor outcome in ICH patients

Background and Purpose: Dehydration is common in hospitalized patients and associated with poor outcome in ischemic stroke patients. Intracerebral hemorrhage patients use hyperosmolar agents frequently after admission,which may lead to dehydration.Since the blood urea nitrogen to creatinine ratio (BUN/Cr) is an indicator of dehydration,it is unknown whether there is a relationship between BUN/Cr ratio during hospitalization and clinical outcome of intracerebral hemorrhage patients. Mehtods: A total of 211 patients with supratentorial cerebral hemorrhage were included. Clinical data was collected retrospectively.BUN/Cr ratio on day 7 after onset (7dBUN/Cr ) was calculated.Poor outcome was defined as 90-day mRS>2. Univariate and multivariate logistic regression analyses were used to determine the relationship between 7dBUN/Cr ratio and 90-day poor outcome. Receiver operating curve was used to determine the best cutoff of 7dBUN/Cr ratio for predicting poor outcome.Results: NIHSS score,hematoma volume and 7dBUN/Cr ratio were independently correlated with 90-day poor outcome. Under receiver operating curve, 7dBUN/Cr ratio exhibited similar prognostic capability, as compared to hematoma volume.The best cutoff for 7dBUN/Cr ratio to predict poor outcome was 22 in the hyperosmolar agents subgroup.Conclusions: Elevated BUN/Cr ratio at day 7 is associated with 90-day poor outcome in ICH patients. Further prospective study will be required to confirm this result and explore the value of BUN/Cr ratio in the application of hyperosmolar agents and hydration therapy. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial Our study is a retrospective study. ### Funding Statement There is no external funding in this study. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was approved by the Ethics Committee of the First Affiliated Hospital of Zhengzhou University(Ethics number,2022-KY-1226-002). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data referred to in the manuscript is available.