Temperature decline is a trigger of subarachnoid hemorrhage: case-crossover study with distributed lag model

Area of Science:

• Environmental epidemiology
• Neurology
• Biostatistics

Background:

• Subarachnoid hemorrhage (SAH) is a critical neurological condition.
• Environmental factors, such as temperature fluctuations, may influence SAH incidence.
• Understanding these associations can aid in public health preparedness.

Purpose of the Study:

• To investigate the association between daily temperature changes and subarachnoid hemorrhage (SAH) incidence.
• To employ a novel statistical test to predict SAH trends in response to temperature.
• To demonstrate the delayed effect of temperature changes on SAH risk within a short hazard period.

Main Methods:

• Retrospective analysis of 1682 SAH patients from January 2005 to September 2019.
• Utilized meteorological data (temperature, pressure, humidity) and case-crossover analysis.
• Applied a distributed lag linear model (DLM) with a 4-day lag period to assess temperature change from the previous day (TCP) and SAH risk.

Main Results:

• A significant association was found between temperature decline and increased SAH risk.
• Cumulative odds ratios (ORs) indicated higher SAH risk with colder temperatures (e.g., OR 2.11 for -6.2°C).
• Temperature decline on the day of SAH onset showed a significant association (OR 1.34), with winter months (December) exhibiting the highest incidence peak.

Conclusions:

• Daily temperature decline from the previous day acts as a trigger for subarachnoid hemorrhage (SAH).
• The impact of temperature change on SAH occurrence is most evident on the day of exposure.
• Findings suggest environmental temperature is a significant, short-term risk factor for SAH.