# Extreme temperature and humidity exposure elevates acute intracerebral hemorrhage risk

## TL;DR

Extreme cold and low humidity increase the risk of acute brain bleeding, with effects peaking hours after exposure.

## Contribution

The study identifies specific time lags and vulnerable subgroups for acute intracerebral hemorrhage risk under extreme weather.

## Key findings

- Extreme low temperatures significantly increase ICH risk, peaking 18 hours post-exposure.
- Low humidity is associated with a transient ICH risk peak at 7 hours post-exposure.
- Lobar and deep hemorrhage patients show higher vulnerability to environmental extremes.

## Abstract

This study examines the association between extreme temperature, relative humidity, and acute intracerebral hemorrhage (ICH) risk using a time-stratified case-crossover design. Data from 2,284 ICH patients in the northwestern region of Hubei Province, China, were analyzed, focusing on extreme environmental conditions. Extreme low temperatures significantly increased ICH risk, peaking around 18 h post exposure, while low humidity was associated with a risk peak at 7 h post exposure. Sensitivity analyses confirmed the robustness of these findings, with extended lag periods showing sustained risk but decreasing magnitude over time. Subgroup analyses revealed higher vulnerability among lobar hemorrhage patients and older adults. These findings highlight the importance of environmental factors, particularly cold and low humidity, in ICH risk and stress the need for targeted public health interventions for vulnerable populations during extreme weather events.

•Time-stratified case-crossover analysis of ICH risk under extreme weather•Cold exposure raised ICH risk, peaking 18 h after exposure•Low humidity had a transient peak effect at 7 h post-exposure•Deep hemorrhage patients showed greater environmental vulnerability

Time-stratified case-crossover analysis of ICH risk under extreme weather

Cold exposure raised ICH risk, peaking 18 h after exposure

Low humidity had a transient peak effect at 7 h post-exposure

Deep hemorrhage patients showed greater environmental vulnerability

Climatology; Neuroscience