Chronic respiratory diseases
Chronic respiratory diseases (CRDs) are diseases of the airways and other structures of the lung. Some of the most common are chronic obstructive pulmonary disease (COPD), asthma, occupational lung diseases and pulmonary hypertension. In addition to tobacco smoke, other risk factors include air pollution, occupational chemicals and dusts, and frequent lower respiratory infections during childhood. CRDs are not curable, however, various forms of treatment that help dilate major air passages and improve shortness of breath can help control symptoms and increase the quality of life for people with the disease.
The WHO Global Alliance against CRDs (GARD) has a vision of a world in which all people breathe freely, and focuses in particular on the needs of people with CRDs in low-income and middle-income countries.
Chronic respiratory diseases
Chronic respiratory diseases are chronic diseases of the airways and other structures of the lung. Some of the most common are:
asthma
chronic obstructive pulmonary disease (COPD)
respiratory allergies
occupational lung diseases and
pulmonary hypertension.
Main risk factors
tobacco smoking
indoor air pollution
outdoor pollution
allergens
occupational risks and vulnerability
Main facts
Hundreds of millions of people suffer every day from chronic respiratory diseases. According to the latest WHO estimates (2004), currently 235 million people have asthma, 64 million people have chronic obstructive pulmonary disease (COPD) while millions have allergic rhinitis and other often-underdiagnosed chronic respiratory diseases.
Other chronic respiratory diseases
Besides asthma and chronic obstructive pulmonary disease, there are many other chronic respiratory diseases. Below is a overview of the most common chronic respiratory diseases.
Allergic rhinitis and sinusitis
Allergic rhinitis, or hay fever, happens when you breathe in something to which you are allergic, and the inside of your nose becomes inflamed and swollen.
Sinusitis is an inflammation of the lining inside the sinuses which can be acute or chronic. When the sinuses become blocked and fill with fluid, germs can grow and cause symptoms such as headache and nasal yellowish secretions. Blocked sinuses can be caused by the common cold, hay fever or nasal polyps (small lumps inside the nose).
Allergic rhinitis and sinusitis are linked to each other, because allergic rhinitis causes your nose to become blocked, and in turn blocks the sinuses.
Causes
Allergic rhinitis is triggered by allergens. Allergens can be found both outdoors and indoors. When allergic rhinitis is caused by outdoor allergens, e.g., mould or trees, grass and weed pollens it is often referred to as seasonal allergies, or hay fever. Allergic rhinitis may also be triggered by allergens found in the home, such as animal
dander, indoor mould, or house dust mites. The most current classification of allergic rhinitis, tough, takes into consideration the intensity of symptoms and the impact on quality of life. According to these characteristics it may be mild or moderate/severe.
Treatment
Acute sinusitis usually subsides without any need for specific treatment. Chronic sinusitis may require antibiotics, decongestants or steroid nasal sprays.
Bronchiectasis
Bronchiectasis is an abnormal widening of one or more airways. Normally, tiny glands in the lining of the airways make a small amount of mucus. Mucus keeps the airways moist and traps any dust and dirt in the inhaled air.
Because bronchiectasis creates an abnormal widening of the airways, extra mucus tends to form and pool in parts of the widened airways. Widened airways with extra mucus are prone to infection.
Causes
The cause of bronchiectasis is often not clear. Some conditions that affect or damage airways can cause the disease, for example:
Some inherited conditions. For example, a condition called primary ciliary dyskinesia affects the cilia so they do not move correctly to clear the mucus. Cystic
fibrosis is another condition that affects the lungs and causes bronchiectasis.
Inhaled objects can become stuck and block an airway. This may lead to local damage to that airway. Acid from the stomach that is regurgitated and inhaled can damage airways as well as inhaling poisonous gases.
Severe lung infections such as tuberculosis (TB), whooping cough, pneumonia or measles can damage the airways at the time of infection. Bronchiectasis may then develop.
Symptom
The main symptom of bronchiectasis is a cough which produces a lot of sputum, tiredness and poor concentration as well as wheeziness. A lung scan and other lung and sputum tests help to confirm the diagnosis.
Treatment includes regular physiotherapy, which helps coughing up and clearing the mucus, and courses of antibiotics. Surgery is occasionally needed.
Obstructive sleep apnoea syndrome
Obstructive sleep apnoea syndrome is a clinical disorder marked by frequent pauses in breathing during sleep usually accompanied by loud snoring. These pauses cut off the oxygen supply to your body for a few seconds and halt the removal of carbon dioxide.
As a result of this, your brain briefly wakes you up, re-opens the airways and re-starts breathing. This can occur many times during the night and makes proper sleep impossible. During the day you may experience excessive daytime sleepiness, difficulty in concentrating or headaches. At night, snoring is the most common feature.
Diagnosis and management
Obstructive sleep apnoea syndrome is diagnosed through polysomnography, a method of recording body activity during sleep; and pulse oximetry, which
measures the amount of oxygen in the blood at any time. Obstructive sleep apnoea syndrome is not a life-threatening condition in itself, but it can result in serious problems such as cardiovascular and cerebrovascular diseases.
The disease can impact on the quality of life, but can be easily managed. One of the treatments is continuous positive airway pressure, which forces air through a mask into the airways so that they do not close.
Pulmonary hypertension
Pulmonary hypertension is a condition in which there is high blood pressure in the lung arteries. How the disease starts is not always clear, but the arteries become narrow and there is less room for the blood to flow.
Over time, some of the arteries may stiffen and become completely blocked. The narrowing of the pulmonary arteries causes the right side of heart to work harder to pump blood through the lungs. Over time, the heart muscle weakens and loses its ability to pump enough blood for the bodys needs.
The extra stress causes the heart to enlarge and become less flexible. Heart failure is one of the most common causes of death in people who have pulmonary hypertension.
Causes
In some cases, pulmonary hypertension is caused by schistosomiasis, a worm infection which is common in Africa and Latin America; and sickle cell disease, a genetic abnormality of blood which is common in persons of African origin.
Symptoms
Difficulty in breathing or shortness of breath is the main symptom of pulmonary hypertension. Other symptoms are fatigue, dizziness, swelling in the ankles or legs (edema), bluish lips and skin (cyanosis), chest pain, racing pulse and palpitations.
Source: WHO
