The Spanish Society of Pneumology and Thoracic Surgery (SEPAR) has warned that high temperatures favor the appearance of symptoms and exacerbations of asthma, increase hospital admissions, and even deaths from COPD, and can harm the evolution of bronchiectasis, although in this last pathology the scientific evidence remains scarcer.
In the context of the SEPAR Year 2026-2027 of the Airway, dedicated to asthma, chronic obstructive pulmonary disease (COPD), and bronchiectasis, specialists emphasize that those suffering from these chronic respiratory diseases present a greater vulnerability to episodes of intense heat.
The available scientific data indicate that heat waves are related to an increase in respiratory morbidity and mortality, especially in the most fragile groups. Although they share common mechanisms, pulmonologists emphasize that the impact is not identical in each pathology.
"In recent years, very interesting works have been published. If I had to highlight one, it would be that of Zhu and collaborators, in which a global view of the evidence available to date is offered, and it highlights that extreme temperatures have a relevant impact on respiratory health, especially in people with chronic respiratory disease," indicated the pulmonologist and member of the SEPAR Year Committee of the Airway, Juan Marco Figueira.
Regarding COPD, Figueira points out that the most recent studies agree in describing an increase in exacerbations, hospital admissions, and mortality during periods of extreme heat. "In bronchiectasis, although we still have less information, studies are beginning to appear that indicate a greater vulnerability to extreme temperatures," he added.
MORE VISITS TO EMERGENCIES FOR ASTHMA
In the case of asthma, high temperatures can trigger symptoms and increase the risk of crises, especially when combined with other environmental factors such as air pollution. The scientific literature suggests that heat episodes hinder disease control and increase the use of health resources.
An international meta-analysis published in "European Respiratory Review" found that heat waves increase the risk of going to the emergency room for asthma exacerbations by 18 percent. Likewise, other research, such as that published in "Thorax," has observed that for every increase of 1 °C in the average summer temperature, the risk of hospitalization for asthma rises by approximately 1.1 percent.
In COPD, the association with heat is particularly marked. A study published in "European Journal of Preventive Cardiology," which analyzed data from 48 Spanish provinces, concludes that high temperatures increase the probability of hospitalization for COPD by 26 percent and the risk of death from this cause by 63 percent, with a particularly pronounced effect on elderly individuals.
Regarding bronchiectasis, the information is still limited, but available studies suggest that heat may also negatively impact the progression of this disease. This is emerging evidence, still not solid, about the role of climate change in this pathology.
Currently, it is known that high temperatures favor the formation of tropospheric ozone, a secondary air pollutant. A study published in "eBioMedicine" observed that an increase in ozone levels (equivalent to the interquartile range [IQR] of 56.1 g/m) was associated with a 4.36 percent increase in mortality from bronchiectasis.
"One of the great challenges we face is adapting to this new reality. Heat waves are no longer exceptional episodes. This means we will have to integrate this factor into our usual clinical practice, reinforcing prevention and offering recommendations to patients to protect themselves during episodes of extreme heat," reports Figueira.
RECOMMENDATIONS FOR HEAT FOR ASTHMA, COPD, AND BRONCHIECTASIS
The main recommendation from SEPAR is to minimize exposure to intense heat, especially during the central hours of the day, and to stay in cool spaces whenever possible. It is also emphasized to maintain adequate hydration and reduce outdoor physical activity during heat waves.
If smoke episodes occur due to wildfires or authorities issue warnings for poor air quality, it is advised to limit outings and follow official guidelines.
Another key point is not to interrupt treatment in summer or during holidays. It is relatively common for some patients to relax adherence when they feel better, but maintaining inhaled medication is one of the most effective strategies to avoid exacerbations.
In those who suffer from bronchiectasis, it is also essential to continue with the usual bronchial hygiene measures and to consult early in case of changes in expectoration or if dyspnea worsens.
In patients on home oxygen therapy, precautions should be taken during heat waves, placing the concentrator in a well-ventilated area and following the guidelines of the healthcare team.
Finally, it is noted that quitting smoking remains the intervention with the greatest impact on the progression of respiratory diseases.