This is how the new Health system works

Represent actual heat exposure

The new definition avoids the generalization of the provincial risk threshold that was used until now and includes other social, demographic and geographic factors in the equation that calculates the temperature from which heat-related death statistics are triggered.

“A single temperature does not represent the real exposure of the population,” explains Díaz, who gives as an example the change from a health alert level of 35.6 ºC for the province of Madrid to values ​​between 34.1 and 35.9 ºC for the three ‘meteohealth’ zones into which the province is divided. The number of weather stations used as a reference is also expanded, because “the exposure to heat of a person who lives in the mountains is not the same as that of another who lives by the sea.”

To all this they have incorporated some conditions that influence the ability to adapt to heat, such as the structure of the populationthe level of renthow prepared they are households or the response capacity of the health system in each territory. The result has been a system that is between 1.6 and 7.6 ºC on average compared to the AEMET meteorological thresholds, according to the DataRTVE calculation.

In general, the temperatures that trigger a health alert are lower than those that would trigger weather warnings. With these new thresholds, Health pursues better risk management. “From a health point of view, it is very important to give the alert when it needs to be given, because, if you don’t give it, there may be mortality that you could have avoided,” argues Julio Díaz.

“As the alert is more selective and more specific, we can act better,” says the president of the Spanish Society of Epidemiology, Óscar Zurriaga, for whom the key is what is done next, especially to protect vulnerable groups such as elderly people who live in nursing homes or people who work outdoors.

More than 50 days of health risk due to heat in the Pyrenees

If this system had been active last year, the health alert threshold temperature for heat would have been exceeded on up to 58 days between June and September in places such as the Costa del Sol and the banks of the Guadalhorce, 52 days in the Pyrenees of Lleida or 49 on the southern coast of Alicante, according to the analysis carried out by ProductosRTVE of the temperatures recorded by AEMET.

The following maps show the average number of days in which these temperatures would have exceeded the new health threshold in each ‘meteohealth’ zone during the summers of this century [Ver metodología].

Avoid heat stroke and other health risks

The new national plan for preventing the effects of excess temperature on health changes in the territorial area it affects, but maintains the criteria for evaluating the risks. Warnings will be issued when three consecutive days of extreme temperatures are expected, with four risk levels.

The plan includes a automatic communication protocol to the population, something that is still being worked on, as RTVE has learned. For now, the activation of alerts only entails coordination with the health authorities of the autonomous communities.

Extreme heat is capable of altering our physical and mental conditions, increasing the risk of mortality, especially in people with previous pathologies. In the last two years alone, excess mortality reports record almost 7,800 deaths attributable to heatand Health points out that the risk increases between 9.1 and 10.7% for each degree that the temperature rises above the health impact threshold.

The most serious and striking effect is that of heatstroke. Although it only represents around 2% of deaths attributable to heat waves, experts warn that it can affect a completely healthy population. “The age group of 18 to 45 years is the only one in which the impact of heat has increased in recent years,” analyzes Carlos III Institute researcher Julio Díaz, who focuses, for example, on people who They work many hours outdoors.

Apart from the most adverse effects, heat causes other types of disorders in the body. “They are more common, but less striking,” points out the coordinator of the Emergency work group of the Spanish Society of Primary Care Physicians (SEMERGEN), which lists cramps, dehydration, fatigue, irritability, nausea or vomiting as symptoms of the heat exhaustion. This is an insufficient physiological response of the thermoregulatory system and a loss of water and electrolytes that can also lead to the worsening of chronic diseases.

Heat also influences the taking of medications such as diuretics, neuroleptics, anticholinergics and tranquilizers, either due to “an alteration of consciousness and perception of reality” or due to imbalances “in arterial and venous dilation and vasoconstriction,” explains Alberto. Kramer. In addition, there are known effects on the skin and eyesight due to excessive exposure to UV rays from the sun; the digestive system, due to excessive fluid intake or the proliferation of food poisoning favored by heat; or mental health.

Impact on health in the medium and long term

Chaining many days of health risk due to heat can put added pressure on Health in the medium and long term. “The impact is not direct on the health system at that very moment other than in some cases, such as heat stroke and some decompensations,” explains epidemiologist Óscar Zurriaga. For the rest of the people with previous or vulnerable pathologies, he adds, there is a deterioration that can even lead to death due to the worsening of his illness.

For Zurriaga, the new alert system presents a “greater reliability” that “gives it extra credibility”, since he believes that the correlation between the sensation of heat that the population has and the issuance of the alert will be clearer when referring to more specific areas. However, there is still work to be done to raise awareness in society.

From the recommendations in the primary care consultation to the civil protection action, for the epidemiologist, the warning system must have an action plan and specific protocols that involve the health system and local and regional administrations. “There is a lack of greater awareness of reality, of what it means [el riesgo sanitario por calor]why are direct effects on people’s health and we are still little aware of it,” concludes Zurriaga.