Asthma is a chronic lung disease characterised by recurrent breathing problems and symptoms such as breathlessness, wheezing, chest tightness, and coughing. During normal breathing, air flows freely into and out of the lungs. But when asthma is not under control, the airways of the lungs become thick, swollen, and inflamed. The airways become overly sensitive to environmental changes, and an asthma attack can happen easily.
During an asthma attack, the lining of the airways swells, muscles around the airways tighten, and mucous clogs the tiny airways in the lungs, making breathing difficult.
Asthma symptoms vary from hour to hour, from day to day, from week to week, and over months. They are often worse at night and in the early hours of the morning. The severity of asthma also varies from individual to individual.
Although asthma cannot be cured, it can be effectively treated. Research shows that with proper treatment, nearly all asthma patients can achieve and maintain good asthma control, enabling them to participate in school, work, and other normal activities while preventing visits to emergency departments.
What Causes Asthma?
The causes of asthma are not well understood, and the rapid increase in asthma prevalence around the world is one of the biggest mysteries in modern medicine. Ten years ago, scientists thought that diesel exhaust and other pollutants might be causing the asthma epidemic. However, they now believe that the picture is more complex.
Many scientists are examining the role of genetic factors in causing asthma, and researchers are also looking at how the immune system develops in early life.
The causes of asthma attacks, however, are better understood. People with asthma have chronic inflammation in their lungs and airways that narrow more easily in response to a variety of factors than those of people without asthma.
The factors that can set off an asthma attack (sometimes called 'triggers') include inhaled allergens (such as dust mites, pollen, and cat and dog allergens), tobacco smoke, air pollution, exercise, strong emotional expressions (such as crying or laughing hard), chemical irritants, and certain drugs (aspirin and beta-blockers).
Each person with asthma reacts to a different set of factors, and identification of these factors and knowing how to avoid them is a major step for each individual in learning how to control their disease.
How is Asthma Diagnosed?
A careful medical history, a physical examination, and tests of lung function provide the information needed to diagnose asthma. Measurement of lung function is useful both for diagnosis of asthma and to monitor the course of the disease and the level of control.
Such tests include spirometry, which provides an assessment of airflow limitation, and peak flow, which measures the maximum speed at which air can flow out of the lungs.
Spirometry is performed in a healthcare professional's office, while peak flow can be tested with portable, plastic peak flow meters ideal for use in home and work settings. Peak flow monitoring provides most patients, together with their healthcare providers, an effective method to monitor their disease and evaluate their response to therapy.
What is Asthma Control and How Is It Achieved?
Although asthma is a chronic condition, it is important to understand that it is a highly controllable disease. The need for good control is essential as an asthma attack can occur at any time if asthma is uncontrolled. Regardless of age, good control over asthma ensures an improved quality of life for patients.
A person with good asthma control would have minimal asthmatic symptoms. Hence, they need not be restricted from physical activities and exercise and can expect to live a healthy and active life.
One of the most serious indicators of lack of asthma control is hospitalisation. Asthma-related hospitalisations pose a heavy social and economic burden, and are an indication that asthma treatment has failed and needs to be improved. The vast majority of emergency visits caused by asthma could be avoided if patients knew how to use medication when their symptoms increase.
Asthma control means that a person with asthma has :
* No (or minimal) asthma symptoms
* No waking at night due to asthma
* No (or minimal) need to use quick- relief medication
* The ability to do normal physical activity and exercise
* Normal (or near-normal) lung function test results (PEF and FEV1)
* No (or very infrequent) asthma attacks
The goal of asthma treatment is to achieve and maintain control of the disease. In order to achieve control, people need access to effective anti-asthma medications, as well as education to understand how to take their medicines, how to avoid risk factors or 'triggers' that make their asthma worse, and what to do if their symptoms do worsen.
Most people with asthma need 2 types of medications : controller medications (especially anti-inflammatory agents such as inhaled glucocorticosteroids) that are taken every day over the long term to keep symptoms and attacks from starting, and reliever medications (rapid-acting bronchodilators) that must be kept on hand at all times to treat attacks or provide quick relief of symptoms.
Asthma affects approximately 300 million people worldwide. The prevalence of the disease is increasing throughout the world, especially as communities adopt Western lifestyles and become urbanised. It is estimated that there may be an additional 100 million persons with asthma by 2025.
Asthma in Malaysia
According to a recent study, the Asia Pacific region recorded a higher rate of absence from work and school due to asthma, with the disease impacting highly on daily activities as a result of poor asthma control compared to the United States or Europe.
In Malaysia, asthma affects approximately 10% to 13% of the total population, with a large majority being under-treated and living poor quality lives. Furthermore, an asthma survey conducted by the Asthma Council Malaysia in 2003 revealed that 66% of asthmatics in Malaysia had never undergone a lung function test.
Approximately 32% of asthmatics reported that they had missed work in a total of 6 days a year due to asthma. Furthermore, 21% of asthmatics had trouble sleeping and 17% were restricted in physical exertion.
On the other hand, 52% of children with asthma missed schools because of their condition. Of this figure:
* 57% were affected in terms of physical activities
* 51% in terms of social activities
* 79% had their sleep interrupted
* 68% had limited participation in sports and recreational activities
* 67% were not on any treatment
These findings are a cause for concern as asthma management in the region fall below the recommended level of care outlined by international expert opinion.
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