With each new heat wave, an observation insistently comes up in epidemiological studies: Women die more than men during heat waves. An imbalance still little publicized but yet well documented by science.
According to a vast Dutch study having reviewed around sixty publications, Women aged over 65 are significantly more vulnerable. A glaring phenomenon during the Historical heat wave of 2003 : in France, the mortality rate of women was then 15 % higher to that of men.
The heat, more deadly in women
Researchers from the University of Amsterdam have confirmed this imbalance in The Netherlandsespecially in the elderly of Over 80 years. However, this gender bias does not seem to exist in the event of extreme cold. On the other hand, as soon as the heat becomes unbearable, the differences appear clearly.
In the summer of 2022 has sadly illustrated it: according to a study published in Medicine nature,, 60,000 people died in Europe During the heat wave. Among them, women represented 56 % of deathsa statistically major gap.
Less perspiration, more vulnerability
To explain this Increased vulnerabilityseveral tracks are advanced. Starting with a simple physiological fact: women sweat about twice as much as men. However, it is through sweat that the body evacuates excess heat.
Hormones also play a significant role. Just before ovulation or during menopausefemale body temperature increases slightly, complicating thermal regulation.
Finally, the morphology comes into account. As explained by Dr. Gérald Kierzek, emergency doctor:
“”Women have a lower body surface than men. They are more quickly invaded by heat. Also, they have a different fat distribution, which can play a role on perspiration “.
A more exposed heart, increased cardiovascular risk
The heat is not content to raise the temperature: it also acts as a major stress for the cardiovascular system. And there again, elderly women seem more exposed.
According to the researcher Inserm Nabila Bouatia-Naji, the heat has a more intense effect on The female heart weakened by age : “The blood pressure rises and the heart must compensate. He pumps, but being more fragile, he has trouble holding “.
Another key point: women are overrepresented among hypertensive people and present an increased risk of stroke, which multiplies the risks in the event of a heat stroke.
Biological differences … but not only
The temperature does not impact everyone in the same way. Each human body has its own “thermostat”. But biological differences are not enough to explain everything: social factors, access to care, isolationAnd clothing habits Can also influence heat -related mortality.
In a scorching period, it is therefore not just a question of feeling. For elderly women, the danger is objectively higher. And prevention policies must take this into account.