In this time of the Ice Saints, a heat wave is expected throughout France between this Monday 9 and Thursday 12 May 2022. Mercury will exceed 25°C on the northern half of the country and will pass the 30°C mark in the South. “The feeling will sometimes become painful with perceived temperatures which will reach 30 to 35° over 2/3 of the territory due to the humidity”, warns La Chaîne Météo. For its part, Météo Villes issues an opinion of “risk of drought and heat wave for summer 2022 in France”. Bad news for cultures but also for our health, and more particularly that of men. According to a study published in the BMJ Open, warmer-than-usual summer nights increase risk of death from cardiovascular disease in early 60s.
Cardiovascular diseases: extreme heat in summer increases the risk of death
Previous research had already investigated the possibility that periods of hot weather during the summer, involving extreme or prolonged heat waves, could coincide with increases in hospitalizations and deaths from cardiovascular disease. However, several inconsistencies did not allow conclusions to be drawn. Researchers at the University of Toronto in Canada therefore decided to investigate any possible link between the high summer temperatures at night and the increase in deaths from cardiovascular disease in people aged 60 and over.
They took data from the Office for National Statistics on adult deaths attributed to heart disease for the months of June and July each year between 2001 and 2015 in England and Wales, as this is during of these two months that heat waves in the UK are the most frequent and intense. To supplement these figures, they also collected corresponding information in King’s County, Washington State, a similar region facing the sea, at a latitude parallel to England and Wales, with properties comparable terrestrial and oceanic atmospheric conditions, with a similar prevalence of residential air conditioning. The US data, however, only included men.
“Given the increasing likelihood of extreme summers in the western US and UK, our results call for preventative population health initiatives and new urban policies aimed at reducing the future risk of cardiovascular events.”detailed the researchers.
Heat wave: very hot nights increase the risk of death from cardiovascular disease
According to their data, between 2001 and 2015, 39,912 deaths from cardiovascular disease (68.9% male) have been recorded in England and Wales and 488 deaths in King County.
In England and Wales, researchers have found thata 1°C increase in usual summer night temperature was associated with a 3.1% increased risk of death from heart disease in men aged 60 to 64, but not in younger or older men or women.
In King’s County, an increase of 1°C was associated with a 4.8% increase in the risk of mortality from cardiovascular disease in people aged 65 and younger, but not in older men.
Worrying findings according to the researchers because in recent years, populated areas such as those studied are experiencing a proportional increase in the intensity of summer heat at night. However, further studies need to be conducted to confirm these results. “L These results should stimulate a similar investigation of exposure and event rates in other mid- to high-latitude populated regions.”, they concluded.