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A Low Mortality Rat Model to Assess Delayed Cerebral Vasospasm After Experimental Subarachnoid Hemorrhage
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Atmospheric Pressure Variation is a Delayed Trigger for Aneurysmal Subarachnoid Hemorrhage
Carlina E van Donkelaar1, Adriaan R E Potgieser1, Henk Groen2
1Department of Neurosurgery, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
World Neurosurgery
|February 8, 2018
Summary
Atmospheric pressure changes, particularly in the days preceding an event, are linked to a higher incidence of spontaneous subarachnoid hemorrhage (SAH). A lower SAH occurrence was observed in July.
Area of Science:
- Neurology
- Environmental Medicine
- Epidemiology
Background:
- Spontaneous subarachnoid hemorrhage (SAH) has a known seasonal pattern, but the underlying causes remain unclear.
- Meteorological data are crucial for understanding the environmental factors influencing SAH incidence.
- Previous studies lacked robust meteorological data to explain seasonal SAH variations.
Purpose of the Study:
- To investigate the seasonal incidence of SAH in the Netherlands.
- To explore the association between SAH and local atmospheric changes.
- To identify potential triggers for spontaneous subarachnoid hemorrhage.
Main Methods:
- An observational cohort study of 1535 spontaneous SAH patients from 2000-2015.
- Linking patient ictus dates with local meteorological data.
- Poisson regression analyses to calculate incidence rate ratios (IRRs) and confidence intervals (CIs).
Main Results:
- Significant association found between atmospheric pressure variations and aneurysmal SAH.
- Increased SAH incidence correlated with pressure changes 2-3 days before the ictus (IRR, 1.11; 95% CI, 1.00-1.23).
- A reduced SAH incidence was observed in July (IRR, 0.67; 95% CI, 0.49-0.92), adjusted for temperature and pressure.
Conclusions:
- Atmospheric pressure variations act as a delayed trigger for aneurysmal SAH.
- A notable decrease in aneurysmal SAH incidence occurs in July.
- Environmental factors, specifically atmospheric pressure, play a role in SAH occurrence.
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