Nearly Half of Acute Stroke Patients are Dehydrated

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patient drinking
Dehydration in stroke can lead to hemoconcentration and vascular sludging.

NASHVILLE — New results have found that 44% of patients admitted for ischemic stroke are dehydrated at the time of admission, suggesting to researchers the possibility of an inexpensive and globally available treatment to optimize functional outcomes in these patients.

For the study, which was presented at the International Stroke Conference 2015, Mona N. Bahouth, MD, of Johns Hopkins Hospital, Baltimore, and fellow researchers enrolled consecutive ischemic stroke patients within 12 hours of their last normal neurological exam. Patients presented at a single academic health system, and those with renal failure or who were unable to undergo magnetic resonance imaging (MRI) were excluded.

Researchers defined dehydration as blood urea nitrogen/creatinine ratio >15 and urine specific gravity >1.010, and determined stroke severity by National Institutes of Health Stroke Scale (NIHSS) score and lesion volume by diffusion weighted MRI.

Of the 383 ischemic stroke admissions surveyed, 168 met inclusion criteria, with 75% having complete laboratory and MRI data.

At admission, 44% of patients were dehydrated. There were no reported differences in demographics between dehydrated and hydrated patients. Researchers found comparable baseline NIHSS score (P=.63) and lesion volumes (P=.48) between groups.

In addition, compared with hydrated patients, those who were dehydrated were in the worst short-term quartile of NIHSS change (42% vs. 17%; P=.02). After adjusting for age, initial NIHSS score, lesion volume and admission glucose, dehydration remained significantly associated with worst NIHSS change (OR=4.34; 95% CI 1.75-10.76).

Limitations and Implications

In his presentation, Bahouth suggested the following study limitations: small sample size; variable timing of MRI; the adequacy of perfusion techniques, which limited calculation of volumetrics; and the non-direct measure of dehydration markers.

Bahouth added that in the future, investigators should define a best approach to volume resuscitation of the dehydrated stroke patient and measure the effect on outcome, which could lead to an inexpensive, safe, and globally available intervention for the acute stroke patient.

According to Albert Favate, MD, chief of the vascular neurology department at NYU Langone Medical Center and assistant professor of neurology at NYU School of Medicine in New York, the results of this study were in line with previous observations.

“Most stroke patients are dehydrated on admission,” Favate told Neurology Advisor. “The state of dehydration can play a role in CNA perfusion, and lead to hemoconcentration and vascular sludging, exacerbating stroke.”

For more coverage of the International Stroke Conference 2015, go here.


  1. Bahouth M et al. Abstract T MP86. Presented at: International Stroke Conference 2015; Feb. 11-13, 2015; Nashville, Tennessee.