A worldwide problem

Asthma is a chronic inflammatory disorder of the airways. It can manifest itself in wheezing, tightness of the chest, or breathlessness. It can begin in childhood, adolescence or adulthood, and may improve or deteriorate with age.

Asthma is a problem worldwide, with an estimated 300 million affected individuals. Absence from school and days lost from work are substantial social and economic consequences of asthma. The World Health Organization has estimated that 15 million disability-adjusted life years (DALYS) are lost annually due to asthma, representing 1% of the total global disease burden.

One way of looking at the problem of asthma might be to say that, if the price of controlling asthma seems high, the cost of not treating asthma – in time lost from work, hospital admissions, and premature death – is even higher.

What causes asthma?

The cause of asthma is one of the greatest unanswered questions in medicine. Some experts say that in future we will speak of ‘asthmas’ – or varieties of asthma – rather than asthma, since many factors seem to be involved.

These factors can be divided into two main camps: ‘host factors’ and ‘environmental factors’. Host factors include those related to genetic inheritance, obesity and gender. Environmental factors include allergens, respiratory infections, tobacco smoke, exercise, strong emotional expression, air pollution, diet and drugs (such as aspirin and beta blockers).

Although host factors are often intractable, it is possible to address environmental factors to improve asthma. Measures can be taken to control house dust mites, for example. Control of pets and other sources of allergens may also be recommended. Exercise-induced asthma can be addressed by various methods, including regular cardiovascular workout.

Medication for asthma

For many people, control of the risk factors will not be sufficient to control asthma. The ‘preventer’ drugs, such as inhaled corticosteroids, can be taken regularly to minimize attacks. The ‘reliever’ group of drugs, such as beta-2 agonists, can be taken when an asthma attack is in progress.