Study: Tropical nights increase the risk of strokes | Life & Knowledge

Every year brings new heat records. And high temperatures at night in particular are increasingly becoming a health risk, as a new study shows.

Researchers at the Helmholtz Zentrum München and the University Hospital Augsburg have investigated the effects of Climate change for the stroke rate. To do this, they evaluated a total of 22,284 strokes that had been treated in the Stroke Unit of Augsburg University Hospital between January 1, 2006, and August 31, 2020.

They assigned these to meteorological data from the weather stations in Augsburg, including air temperature, relative humidity, ozone and Fine dust pollutionThe HNE index was used to determine nighttime heat stress.

Two time periods were compared, one from 2006 to 2012 and one from 2013 to 2020. Result: Between the two periods, the HNE index increased, the number of hot nights rose from 79 to 82. On these nights, the Stroke risk increased significantly, as the figures show. “For example, hot nights from 2006 to 2012 (…) resulted in two additional strokes per year, and from 2013 to 2020 there were already 33 additional cases per year,” says Prof. Markus Naumann, co-author of the study.

Dehydration and disrupted sleep patterns

Reasons for the higher risk of stroke could be nighttime dehydration, but also that the heat affects the regulation of body temperature and thus the natural Sleep rhythm is interrupted. Prof. Naumann: “Everyone knows that on hot nights you sleep badly, wake up often and do not reach the restful deep sleep phases. But these are important for the regeneration of the brain.”

Particularly at risk were According to the study Women and people over 65. But also for younger people and Men There is no all-clear. They showed a significant risk of stroke due to heat stress between 2013 and 2020. In the years before that, the nighttime heat did not seem to have had any influence on their risk of stroke.

By the way: The study only evaluated data up to 2020. The record heat years of 2022 and 2023 were not included yet…