Scottish research suggests that dehydration appears to be common among hospital-admitted stroke patients and is associated with poor outcomes. At any point during their admission in the study, 62% of stroke patients were dehydrated. Death or dependence at hospital discharge was significantly more likely for patients who were dehydrated when compared with those who were not. Independent risk factors for dehydration included:

Female gender.
Total anterior circulation syndrome.
Older age.
Prescribed diuretics.

Abstract: Stroke, December 8, 2011 (online).