In a recent study, researchers from Helmholtz Munich and the University Hospital Augsburg showed that nighttime heat significantly increases the danger of stroke. The findings could help develop preventive measures: they might help people higher protect themselves against the risks of climate change as hot nights turn into more frequent. Moreover, knowledge about the implications of hot nights can improve patient care.

Climate change is causing increasingly more extreme weather events. These include extremely hot, so-called tropical nights. A research team led by Dr. Alexandra Schneider examined the impact of nighttime heat on stroke risk. “We wanted to know the extent to which high temperatures at night pose a health risk”says the pinnacle of the working group on environmental risks at Helmholtz Munich.This is significant because climate change is causing nighttime temperatures to rise much faster than daytime temperatures.“

Data on 11,000 strokes over 15 years

Of their study, scientists analyzed data from the University Hospital Augsburg. His Department of Neurology has collected data on roughly 11,000 strokes over 15 years. Evaluation shows that extreme heat at night increases the danger of stroke by seven percent. “The elderly and girls are particularly in danger, and in clinics after hot nights, strokes with mild symptoms are mainly diagnosed,” says the lead writer of the study, Dr. Cheng He: “Our results clearly show that changes to urban planning and the health care system are extremely necessary to cut back the risks posed by rising temperatures at nightThat is much more true because “We were capable of show that the danger of stroke related to high night temperatures increased significantly in 2013–2020 in comparison with 2006–2012,“, emphasizes prof. Michael Ertl, head of the stroke department and neurovascular working group of the University Hospital Augsburg. Between 2006 and 2012, hot nights caused two additional strokes per yr within the study area; There have been 33 additional cases per yr between 2013 and 2020.

Recommendations for adaptation strategies and concrete planning

The researchers plan to place their findings into practice. To this end, they’re working on recommendations for public adaptation strategies and concrete planning, equivalent to reducing the intensity of urban heat islands. The aim is to higher protect the population against the consequences of night heat. The study may even function a basis for further research to develop targeted preventive measures against aspects contributing to stroke. “The earlier these preventive measures are implemented, the higher” says Alexandra Schneider. The study results are also of great importance for hospitals. In the long run, they are going to have the ability to higher adapt to the frequency of strokes: if the weather forecast predicts a hot night, you possibly can expect more. This may allow clinics to offer more staff to look after patients, explains Prof. Markus Naumann, director of the University Neurological Hospital Augsburg.

Background: What are tropical nights?

“Tropical nights” are defined by the so-called “Hot Night Excess Index” (HNE). It measures how much the temperature rises above a certain threshold at night. The brink value is a temperature that’s exceeded only through the five percent of the warmest nights over your complete study period. On this study, the worth is 14.6°C. If the temperature rises above this value at night, the night is classed as a tropical night. The HNE index adds up what number of degrees the temperature exceeds this threshold during nighttime hours to find out the intensity of warmth.