Asthma is a chronic disease characterized by recurrent attacks of breathlessness and wheezing. During an asthma attack, the lining of the bronchial tubes (airways) swells, causing the airways to narrow, turn more sensitive to irritants in the environment, and thus reducing the flow of air into and out of the lungs. The causes of asthma are not completely understood.
However, risk factors for developing asthma include inhaling asthma “triggers”, such as allergens (some common to all and some individualized), tobacco smoke and chemical irritants. Several patients with asthma may also have allergic rhinitis which is characterized by sneezing and “runny” nose. It can start at any age. About half of all people with asthma tend to have their first symptoms by the age of ten years, and many children with asthma have had their first asthma attack before the age of six. Asthma cannot be cured, but appropriate management can control the disorder and enable people to enjoy a good quality of life.
Symptoms of Asthma
Asthma symptoms can vary in severity with time, can come and go, there may be good and bad periods. Asthma is characterized by:
- Recurrent episodes of wheezing
- Shortness of breath
- Chest tightness
Coughing-sometimes cough may be the only symptom of asthma
Sputum may be produced from the lung due to coughing, small in volume and often in the form of threads and plugs. Symptoms are generally worse at night and in the early morning or in response to allergens.
When uncontrolled, there may be acute asthma attacks often occurring after viral infections (flu, cold), allergen/irritant exposure (pets, pollen, dust, atmospheric pollution, tobacco smoke), exercise, weather changes, medications (aspirin). Danger signs of an acute asthma attack are symptoms not improving after airway-opener inhaler medication, and difficulty in talking due to breathlessness, peak flow-meter readings ranging below 50% of normal value, and require urgent medical attention.
A number of other health conditions are found associated with asthma including:
- Gastro-esophageal reflux disease (GERD)
- Obstructive sleep apnea
Causes of Asthma
The exact cause of asthma is yet not known. But there are certain risk factors that are associated with asthma. It is probably caused by interplay of hereditary and environmental factors.
Some of the factors include:
- An inherited tendency to develop allergies, called atopy (AT-o-pe). Children with eczema or food allergy are more likely than other children to develop asthma.
- Parents who have asthma (heredity).
- Allergens from dust, animal fur, cockroaches, mold, and pollens from trees, grasses, and flowers etc.
- Irritants such as cigarette smoke, air pollution, chemicals or dust in the workplace and sprays (such as hair spray).
- Medicines such as aspirin or other non steroidal anti-inflammatory drugs and nonselective beta-blockers.
- Sulfites in foods and drinks
- Viral upper respiratory infections, such as colds
- Physical activity, including exercise
- Contact with some airborne allergens or exposure to some viral infections in infancy or in early childhood when the immune system is developing.
Diagnosis of Asthma
Medical History: Doctor may also ask:
-About one’s medical history, including information about allergies, asthma, or other medical conditions.
-If one had heartburn or a sour taste in the mouth. These may be signs of gastro esophageal reflux disease (GERD).
-If one had cold or an episode of flu-like symptoms.
-If one smokes or spends time around others who smoke.
Physical Examination & Investigations:
To check for signs of problems related to cough; your doctor will use a stethoscope to listen to your lungs. He or she will listen for wheezing (a whistling or squeaky sound when you breathe) or other abnormal sounds. Other tests may include:
-Chest x ray takes a picture of heart and lungs. This test can help diagnose conditions such as pneumonia and lung cancer.
-Lung function tests: These are detailed tests that can measure how much air you can breathe in and out, how fast you can breathe air out, and how well your lungs deliver oxygen to your blood. Lung function tests can help diagnose asthma and other conditions.
-Peak-flow-meter is a simple hand-held instrument that can be used by you to measure one aspect of lung function and monitor your asthma control. It helps in deciding if someone has asthma, determine how bad an asthma attack as well as assess the degree of asthma control. Your doctor can guide you in its use at home, so that you can be cautious about how to increase asthma medication and when seek urgent medical help.
-An X- ray of the sinuses: This test can help diagnose a sinus infection.
Management of Asthma
Medications: Medicines in asthma is generally given through the inhaled route. “Metered dose” and “dry powder” inhalers are equally effective for long term use, the “nebulized” form being generally used during acute attacks. Inhaling a drug is an effective way of taking an asthma medicine as it goes straight to the lungs, with very little ending up elsewhere in the body. There are two types of inhaled medications. Since asthma is an inflammatory disease, preventer medication should not be discontinued without medical advice.
“Airway-opening medication or Quick-Relief” (Reliever) inhaler: The inhaler usually contains a short-acting beta 2-agonist. It works by relaxing the muscles surrounding the narrowed airways. Examples of reliever medicines include salbutamol, levo-salbutamol and terbutaline. They are utilized in stopping asthma attacks.
“Controller medication” (Preventer) inhaler: It works to reduce the amount of inflammation and ‘twitchiness’ in the airways and prevent asthma attacks occurring. Examples of preventer inhalers are beclomethasone, budesonide, fluticasone and mometasone; often combination of these drugs with long-acting bronchodilators like salmeterol and formoterol are used as preventers to stop asthma attacks from starting and thus protect lung function.
Short courses of corticosteroid and other drugs (oral or injectable) may be required during acute attacks and are to be used after medical advice only.
An asthma patient should learn from the care-provider the correct method of using the inhalation devices (metered-dose inhalers, dry-powder inhalers, spacers, etc) used for the medication and always carry the quick-reliever medication with him/her.
Complications of Asthma
– Symptoms that interfere with sleep, work or recreational activities
– Permanent narrowing of the bronchial tubes (airway remodelling) that affects how well you can breathe
– Sick days from work or school during asthma flare-ups
– Side effects from long-term use of some medications used to stabilize severe asthma
Acheiving Control Over Asthma
Although not curable, good control of asthma can be easily achieved. When under control, the asthma patient can lead a perfectly normal life, work, attend classes, take part in sports, avoid most asthma attacks and sleep well. In order to achieve asthma control the asthma medication has to be taken as advised by the physician and one should also avoid things that trigger asthma attacks which may include animals with fur, cigarette smoke, smoke, dust from sweeping, dust in beds and pillows, strong smells, pollen, inclement weather, and colds. One should also well acquaint with symptoms and signs of worsening of asthma control and know how to respond to it.
Preventer medicines (inhaled form) can, if so advised, be taken regularly on long term basis and are not habit forming. It may be necessary to take the preventive medicine every day if one coughs and wheezes or has a tight chest more than twice a week, wakes up at night due to asthma attacks, or has to use the reliever medication more often than twice a week to stop an asthma attack. A carefully decided self-monitoring of symptoms as well as an asthma treatment plan should be designed for every patient by the care provider and discussed in detail.
Special populations like pregnancy, obesity and elderly subjects need special attention for control of asthma.