Heatwave can trigger severe allergic asthma, study warns

Globally, asthma is one of the most prevalent chronic diseases that affects 300 million people across the world and is expected to increase by 100 million by 2025. Exposure to triggers like outdoor pollution, viruses, pollen and other environmental factors increases the risk of new onset asthma and asthma-related outcomes.

Interestingly, apart from environmental pollutants, studies have found a strong correlation between extreme temperatures and allergic asthma. Studies have found that extreme heat poses a considerable impact on asthma and may pose as an important trigger.

Extreme heat and asthma: Understanding the connection

In an interview with HT Lifestyle, Dr Vijay Warad, Consultant Allergist at Sahyadri Hospital in Pune, explained, “Extreme heat leads to fluid loss in the body, which impacts the blood circulation in the body including to the lungs. Since the pulmonary function is impacted due to heat, asthma patients may witness an attack and breathlessness. Moreover, the extreme heat and humid weather conditions can increase the levels of the air pollutants, mites and common allergens leading to increase asthma attack. There has been a strong correlation where higher ambient carbon-dioxide concentrations and warmer temperatures results in increased pollen production, especially in the urban areas.”

He elaborated, “These particles in the air can irritate sensitive airways and can lead to allergic asthma. Experts predict worsening heatwaves in the near future and significant increase in allergic asthma cases. As temperatures increase, dust particles also increase with increasing potency of allergens. Due to global warming, pollen seasons are extended. During winter again, due to smog, these pollens present in the air are trapped down, alongwith vehicle exhaust, dust and construction dust. Talking about rural areas, because of pesticides overuse these pollen potency has increased.”

Precautions to be taken
With such extreme heat conditions in major cities of India, Dr Vijay Warad suggested some precautions that one should consider –

Stay hydrated: To avoid body fluid loss, one must stay hydrated and ensure blood circulation and maintain pulmonary function
Stay indoors as far as possible, to avoid outdoor pollution: One must stay indoors as far as possible. In case need be, proper precautions need to be taken while travelling outside and avoid travelling out between 11 am to 3 pm when the weather condition are extreme.
If indoors, keep windows closed to avoid exposure to pollution: It is not that only outdoor pollution affects asthma. If one stays indoors, proper precautions like keeping windows closed, using air humidifiers and air conditioners is recommended.

Monitor asthma symptoms: Apart from precautions, one must be aware of asthma symptoms like breathlessness, chest tightness, irritation in the nasal pathways etc.

Proper dust and pollen filter mask to be used. Even car air conditioner should have pollen filters to avoid exposure.

Be aware of weather forecast, information on seasonal variations and aeroallergens levels in environment and plan your schedule accordingly: One must be aware of the weather forecast for the city and plan their schedule accordingly. Avoid heatwave alert days and orange/ red alert days to prevent complications.

By following these precautions, one can manage their allergies better and prevent triggers that cause allergic asthma. Heatwave and extreme conditions increase the chances of allergic asthma. It is important to talk to your doctor in case any symptoms persist and manage the condition with right measures.