Yonsei Med J.  2021 Jul;62(7):600-607. 10.3349/ymj.2021.62.7.600.

Association between Plasma Osmolality and Case Fatality within 1 Year after Severe Acute Ischemic Stroke

• Liu M
• Deng Y
• Cheng Y
• Hao Z
• Wu S
• Liu M

• KMID: 2516852
• DOI: http://doi.org/10.3349/ymj.2021.62.7.600

Abstract

Purpose
Plasma osmolality, a marker of dehydration, is associated with cardiovascular mortality. We aimed to investigate whether elevated plasma osmolality is associated with case fatality within 1 year after severe acute ischemic stroke.
Materials and Methods
We included severe ischemic stroke patients (defined as National Institutes of Health Stroke Scale ≥15 score) within 24 hours from symptom onset admitted to the Department of Neurology, West China Hospital between January 2017 and June 2019. Admission plasma osmolality was calculated using the equation 1.86 * (sodium+potassium)+1.15 * glucose+urea+14. Elevated plasma osmolality was defined as plasma osmolality >296 mOsm/kg, indicating a state of dehydration. Study outcomes included 3-month and 1-year case fatalities. Multivariable logistic regression was performed to determine independent associations between plasma osmolality and case fatalities at different time points.
Results
A total of 265 patients with severe acute ischemic stroke were included. The mean age was 71.2±13.1 years, with 51.3% being males. Among the included patients, case fatalities were recorded for 31.7% (84/265) at 3 months and 39.6% (105/265) at 1 year. Elevated plasma osmolality (dehydration) was associated with 3-month case fatality [odds ratio (OR) 1.98, 95% confidence interval (CI) 1.07–3.66, p=0.029], but not 1-year case fatality (OR 1.51, 95% CI 0.84–2.72, p=0.165), after full adjustment for confounding factors.
Conclusion
Elevated plasma osmolality was independently associated with 3-month case fatality, but not 1-year case fatality, for severe acute ischemic stroke.

Keyword

Plasma osmolality; dehydration; severe acute ischemic stroke; case fatality