Objective:

The aim of this study is to conduct a systematic review and meta-analysis to evaluate the association between hyponatremia and mortality in adult patients with acute ischemic or hemorrhagic stroke.

Background:

Hyponatremia is the most common electrolyte abnormality in stroke patients. Multiple studies reported that sodium abnormalities at the time of admission is linked to higher in-hospital mortality, poorer neurological status, and longer hospital stays.

Design/Methods:

This meta-analysis included retrospective and prospective cohort studies and cross-sectional studies. We searched medical databases including PubMed, Embase, and screened additional journals such as Cureus from 2010 to 2025 following PRISMA guidelines for systematic review and meta-analysis. Data analysis was performed using R software (version 4.5.1). Combined odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using a random-effects model to analyze the data. ChatGPT (GPT-5) was used to troubleshoot an error in R programming during data analysis. All AI-assisted outputs were reviewed and verified by the authors.

Results:

Six retrospective and two prospective observational cohorts, as well as one cross-sectional study, were analyzed. Our pooled analysis of 9 studies including 19,469 patients showed hyponatremia to be associated with worse outcomes. The random-effects model gave an odds ratio of 1.81 (95% CI: 1.31–2.51, p < 0.0003), indicating that stroke patients with low sodium have an 81% higher odds of mortality compared to patients with normal sodium levels. Heterogeneity was high (I² = 92.8%), suggesting variability between these studies. These findings highlight hyponatremia as a significant prognostic factor for mortality in acute stroke patients.

Conclusions:

Hyponatremia is associated with increased mortality in patients with ischemic or hemorrhagic stroke, reinforcing the importance of electrolyte monitoring and early intervention.