Dehydration Status is Associated With More Severe Hemispatial Neglect After Stroke

Many stroke patients are clinically dehydrated at the time of hospital presentation, which could lead to an increase in blood viscosity and alteration in cerebral perfusion. Impaired cerebral perfusion can cause hemispheric dysfunction, which can be rapidly quantified with bedside tests of hemispatial neglect. We hypothesized that hospitalized patients with laboratory markers consistent with dehydration or a volume contracted state (VCS) would have more severe cerebral dysfunction defined by greater degree of neglect.

Subjects were a consecutive series of right-handed patients with acute right hemispheric stroke admitted within the Johns Hopkins Health System. All participants had clinical syndrome and magnetic resonance imaging consistent with acute infarction. The primary definition of a VCS was a urea/creatinine ratio >15, with secondary definition including urine specific gravity over 1.010. Acute infarct volume was measured on magnetic resonance imaging. Neglect was evaluated using a standardized battery of bedside tests.

Of 201 patients meeting inclusion criteria, 131/201 (65%) had elevated BUN/creatinine ratios at admission. Approximately 61% (122/201) had some degree of neglect. Elevated BUN/creatinine ratio was associated with an increased odds of severe neglect in unadjusted models (OR=4.1; 95% CI, 1.2, 14.4), with loss of significance in adjusted models (OR=4.43; 95% CI, 0.99, 19.8) after adjustment for age, infarct volume, sex, and NIHSS score.

Our data suggest that patients who are in a VCS at the time of stroke may have more frequent and severe neglect, with attenuation of results after adjustment for factors related to stroke size and age. If proven clinically relevant, a formalized rehydration strategy based on objective lab markers may represent an opportunity for improvement in outcome with low-cost, broadly available treatment for acute stroke patients.