Asthma is a chronic disease characterised by recurrent attacks of breathlessness and wheezing, which vary in severity and frequency from person to person.
The World Health Organization (WHO) estimates that there are currently about 235 million people worldwide who suffer from asthma.
It is also the most common chronic disease among children.
Assessing asthma control
An asthma attack occurs when the linings of the bronchial tubes swell. This causes the airways to narrow, which reduces the airflow in and out of the lungs.
According to the WHO, the strongest risk factors for asthma are a combination of genetic predisposition with environmental exposure to particles being inhaled.
Your asthma can be controlled with the help of medication and by avoiding triggers that irritate and inflame your airways.
Asthma severity is assessed only at the first consultation to decide which initial treatment to start, but after this your doctor will use a guideline to assess asthma control in order to guide decisions to either maintain or adjust therapy.
The following categories are used to indicate the severity of your asthma:
If you have symptoms of wheezing and coughing for not more than two days a week, you are considered to have intermittent asthma.
Outside of these few episodes, you will not experience any other asthma symptoms.
Anyone with asthma symptoms that last more than two days a week or two nights per month, on average, is then no longer considered to have intermittent asthma but persistent asthma. Persistent asthma has 3 levels of severity.
Mild persistent asthma
With mild persistent asthma, symptoms occur more than twice a week but less than once a day.
Nighttime flare-ups occur more than twice a month but less than once a week. Lung function is 80% of normal or even greater.
Moderate persistent asthma
If your symptoms occur daily, your asthma is classified as moderate persistent.
Flare-ups also occur and last on average seven days.
Coughing and wheezing may disrupt your daily activities and make it difficult to sleep. Nighttime flare-ups may occur more than once a week. In moderate persistent asthma, lung function is roughly between 60% and 80% of normal and that is without treatment.
Severe persistent asthma
If your symptoms occur daily and often, you will be considered to have severe persistent asthma.
Your symptoms will frequently curtail your day to day activities and disrupt your sleep. Lung function is less than 60% of the normal level without treatment. Severe is the least common asthma level.
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