Renal Function as a Predictor of Mortality and Functional Outcomes in Acute Stroke: A Prospective Study

Stroke is a leading cause of global morbidity and mortality, and understanding modifiable predictors of stroke outcomes is crucial. This study explores the relationship between renal function, assessed via estimated glomerular filtration rate (eGFR) and serum creatinine, and stroke mortality and functional outcomes in a cohort of acute stroke patients in India.

A prospective observational study was conducted from February 2021 to October 2022, including 104 acute stroke patients from MS Ramaiah Medical College and Hospital, Bengaluru, India. Patients were categorized into ischemic and hemorrhagic stroke groups. Data collected included demographic information, clinical history, and laboratory results. Functional outcomes were measured using the Modified Rankin Scale (mRS) at admission, day 7, and discharge. Renal function was evaluated using serum creatinine and eGFR. Statistical analyses, including multiple logistic regression, were performed to identify predictors of mortality.

The mean age of participants was 62.2 years, with a male predominance of 75 (72.1%). Hemorrhagic stroke patients had higher mortality rates compared to ischemic stroke patients (p = 0.006). Elevated serum creatinine and decreased eGFR were significantly associated with poorer outcomes. The eGFR at admission was lower in hemorrhagic stroke patients (55.6 ± 34.2 mL/min) compared to ischemic stroke patients (67.3 ± 29.6 mL/min; p = 0.048). Multiple logistic regression revealed that hemorrhagic stroke (OR = 0.17; 95% CI: 0.06 - 0.50) and age (OR = 1.06; 95% CI) were independent predictors of mortality. The threshold values for predicting mortality risk were 1.495 mg/dL for serum creatinine (sensitivity: 69.6%, specificity: 81.8%) and 48.5 mL/min for eGFR (sensitivity: 86.4%, specificity: 69.5%). These thresholds exhibited strong performance in assessing mortality risk, with AUCs (Area Under the Curve) of 0.765 for serum creatinine and 0.786 for eGFR.

Renal function indicators, specifically serum creatinine, and eGFR, are significant predictors of mortality and functional outcomes in acute stroke patients. Hemorrhagic stroke is associated with higher mortality and poorer renal function compared to ischemic stroke. These findings highlight the importance of assessing renal function in stroke management and suggest further research with larger cohorts to refine predictive models for stroke outcomes.