This is a sub-category of All respiratory deaths (see Map 10).

See also Map 63 Bronchitis, Map 88 Chronic lower respiratory diseases, Map 94 Industrial lung diseases, Map 97 Other respiratory disorders, Map 102 Influenza and Map 105 Pneumonia.

Both male and female maps show clusters of high SMRs in south Wales, Blackpool, Pontefract, Exeter and Coventry, with the male cluster extending west across Birmingham. The male and female maps then show a slightly different picture, with females tending to have higher rates in the northern half of the country, and males along the south coast and around the boundary between Inner and Outer London – perhaps reflecting the route of the North and South circular roads.

Asthma affects the airways of the lungs (the bronchi) causing them to become inflamed and swollen. In a person who has asthma the bronchi are more sensitive than normal and certain triggers can irritate them. Common triggers include house dust mites, animal fur, pollen, tobacco smoke, cold air, chest infections, chemical fumes and certain medicines. When this irritation occurs the bronchi become narrow and tighten, causing wheezing and coughing and making it difficult to breathe.

The symptoms can vary from mild to severe. The severe onset of symptoms is known as an asthma attack; it is these asthma attacks that can be life-threatening.

Six out of ten of the people dying from this cause of death are female. It has been suggested that hormonal changes as a result of the menopause might explain the greater number of asthma attacks among older women; among younger women asthma has been found to be related to stages of the menstrual cycle.