Useful facts on asthma and cold (astma og kulde)
Asthma and cold temperatures
Useful information concerning asthma and cold temperatures – NAAF’s fact sheet
Cold weather brings with it extra challenges for people with asthma and airway problems. However, with good preventive measures, appropriate medication and prevention of exposure to cold, asthmatics can still go out in the winter weather.
Cold alone is often not the biggest problem. Particle contamination as a result of cold weather, particularly in towns and built-up areas, will often exacerbate symptoms of asthma. Frequent colds in the winter season will also be associated with worsening of symptoms. Asthma is a disease with many manifestations; however, most asthmatics will feel discomfort in cold weather. It is important to be careful during strenuous exercise in very cold weather (< 10°C).
What happens with asthma in cold weather?
The reason why many asthmatics suffer worsening of symptoms when breathing in cold air is due to hypersensitive airways and not a cold allergy. Inspiration of cold air leads indirectly to drying out and subsequent constriction of the airways.
Breathing in through the nose is also more difficult in extremely cold weather. In asthmatics, mouth breathing leads to even more constriction of the airways, as the air is not pre-warmed as it is breathed in.
The nose plays a very important role in protecting the airways against untreated air, and it has been shown that the size of the nose has an impact on the ability to breathe through the nose. The Inuit live in an extremely cold climate (Greenland) and studies have shown that they have higher nasal cavities than many other ethnic groups
Asthma, cold and exercise
It is important to be aware that exercise in extreme cold can lead to exacerbation of asthma if appropriate protective measures are not taken. So-called exercise-induced asthma may be made worse indirectly by strenuous exercise in cold weather because of an excess supply of cold air into the airways. Problems with exercise-induced asthma often occur as a result of strenuous exercise or competition at temperatures lower than minus 15oC.
Normal airways can also to some degree react to exertion in cold weather – both in animals and humans. Tissue samples from the respiratory passages of sled dogs which have taken part in Alaskan dog-sled races have shown various degrees of inflammatory reactions – exactly the same reaction shown in our cross-country skiers when competing in cold weather.
It is nonetheless important to remember that physical activity improves fitness and the ability to manage asthma. Asthmatics are able to participate in regular activity, including in cold weather, providing they are well protected against cold air at the nose and mouth and with the appropriate amounts of individually-adjusted asthma medication. In general, asthmatics should not perform fitness training at temperatures lower than -10oC.
However, asthma conditions are highly individual, with fluctuations during the course of the condition, and some people will notice breathing problems even at just a couple of degrees below freezing. It is important to have knowledge of your own illness and to take your own personal reactions into account.
Cold-induced asthma is not the same as cold-allergy!
Cold allergy takes the form of urticaria (“nettle rash”) occurring on exposure, especially to cold water. Urticaria as a result of cold or cold water can lead to serious reactions such as swelling involving large areas of the body. Cold allergy can be a cause of allergic shock.
Asthma, cold and particle contamination
In towns and built-up areas, cold days with minimal wind and high traffic density will result in increased concentrations of gases and particles in the air. Nitrogen dioxide (NO2) from diesel engines may contribute to increased air contamination.
In vulnerable groups, breathing nitrogen dioxide (NO2) can lead to increased coughing, bronchitis and reduced resistance to infections. Asthmatics react with reduced lung function even after brief exposure.
Airborne dust can both cause and exacerbate illness in persons with chronic airway conditions. Airborne dust can also be a carrier of allergens that can provoke allergies.
Protection/Prevention - asthma and cold
The Jonas cold weather mask from the Norwegian Asthma and Allergy Association (NAAF) provides good protection against cold and dry air and is well-suited to asthmatics who feel that their asthma worsens in cold weather.
The Jonas mask also provides good protection when exercising in cold weather. A beanie, buff or scarf with a mesh ensures that the air is warmed up before it enters the lungs, thereby reducing the problems encountered by asthmatics and others who have problems breathing cold air into the lungs through the nose.
The Jonas mask is approved as a treatment technical aid and may be subsidised by your health provider, via a requisition from a specialist.