COPD, the medical abbreviation for chronic obstructed pulmonary disease, develops over time and symptoms start to appear after the age of 35 to 40 years.
There are a number of causes and risk factors, which contribute and predispose to developing the COPD disease and its symptoms. These are the same factors, which can also exacerbate or cause a flare-up of an existing COPD.
Smoking is the leading COPD cause and risk factor. However, there are other causes besides smoking that can cause this respiratory disease. These causes can be a potential threat and you can fall prey to them even if you don’t smoke.
COPD causes and factors that increase the risk
Chronic tobacco or cigarette smoking is the major risk factor for developing COPD. Approximately 20% of people who smoke develop this lung disease.
Pipe smoking, cigar smoking, marijuana smoking and people constantly exposed to second-hand smoke are also high-risk candidates. Smoking is the major risk factor in the rich or the developed countries.
What causes COPD in smokers?
Cigarette smoke contains hundred trillion oxidants and over 4,000 toxic chemical compounds. Each time you inhale the cigarette smoke, your lungs are burdened with these toxins, which slowly damage your delicate lung tissue. You could read about the pathophysiological changes that COPD causes in the lungs for a better overview.
Most of the epithelial cells lining the airways in the lungs are covered with cilia. Cilia are slender, microscopic, hair-like structures that are situated on the surface of nearly all mammalian cells.
The cilia serve the function of propelling the mucus and any inhaled pathogens (e.g. bacteria) up the airways and out of the lungs.
Smoke, whether from tobacco or from the polluted environment entering the lungs, destroys the cilia and this is called ciliopathy.
The cilia begin to lose their function and the mucus and inhaled pathogens start accumulating in the lungs.
Over time, the patient starts developing cough and shortness of breath or breathlessness indicating that the normal function of the lungs is slowly but surely getting disturbed.
As the smoking continues, the lungs go on being progressively damaged. This is what causes the COPD to progress and get worse and the reason for breathlessness.
The damage to the lungs is indicated by the following factors:
- The alveolar walls become thick, inflamed, and damaged.
- The bronchial walls, too, get inflamed.
- The cilia of the cells lining the bronchial walls lose their function due to ciliopathy.
- This leads to more mucus being secreted and getting accumulated in the lungs.
- In healthy people, the bronchioles and the alveoli are elastic, so that they inflate and deflate when you breathe in and out. In COPD, the bronchial and the alveolar walls lose their elasticity and become fibrotic and thick. This causes narrowing of the lumen of the small airways, leading to inadequate inhalation and improper gas exchange in the lungs. This means less oxygen and more carbon dioxide in the circulating blood.
All these pathophysiological changes cause chronic bronchitis and emphysema. Chronic bronchitis involves a long-term cough with excessive mucus production. Emphysema involves a slow destruction of the lungs over a period of time.
Long-term cigarette smokers are ten times more likely to suffer from COPD than people who never smoke.
According to the Centers for Disease Control and Prevention (CDC), 80% of the people who die of COPD are smokers. Nonetheless, 1 out 4 Americans who develop COPD never smoked. These are the victims who developed COPD due to other causes besides smoking.
Causes of COPD besides smoking
There are other causes of COPD, which can overcome you even if you do not smoke. They can include occupational causes, low-income compulsions such as using biomass fuel or wood for cooking, frequent respiratory tract infections in childhood, nutritional deficiency, and modern day air pollution.
Though tobacco smoking is the major cause, these causes can be a potential threat in nonsmokers.
Burning of fuel for cooking in kitchens
Burning fuel for cooking and exposure to its fumes in poorly ventilated kitchens is the primary cause of COPD in non-smoking females. This is especially true of women in the developing or low-income countries who use this type of method for cooking.
About three billion people mostly from developing countries use biomass fuel and coal for cooking and heating.
Inhalation of these fumes over long-term increases the CPOD risk. Poor ventilation increases the pollution in the kitchen and the homes, thereby adding to the risk.
This risk factor is responsible for about two million deaths of women and children in Africa, Asia, and the Middle East.
Air pollution and occupational causes
Long-term exposure to other lung damaging gases such as polluted air, chemical fumes and dust particles in the air also contributes to developing COPD.
Occupational causes of COPD are another concern for people who work in polluting industries. These causes include constant exposure to occupational dust, chemicals, soot, pesticides, cleaning solvents, formaldehyde, volatile organic compounds, etc. These are potential reasons for developing COPD in people working in such industries.
Previous lung infections
Previous infection of pulmonary tuberculosis and repeated other lower respiratory infections in early life (childhood) are other contributory factors.
A chronic cough with sputum indicates lung infection and people periodically suffering from this type of a cough should take complete treatment and preventive measures.
25% of COPD patients suffer from asthma.
People, who have bronchial asthma and who also smoke are at a very high risk of developing this respiratory disease. In such people, the disease progresses faster than in people with asthma who do not smoke.
Secondly, though we do not see COPD in children, those who suffer from bronchial asthma at that young age are very likely to suffer from it in later years.
COPD age factor risk in the elderly
Age is another risk factor. COPD develops gradually over the years. Its symptoms are, therefore, seen developing after the age of 35 to 40 years.
It can be hard for the elderly people above the age of 60 years.
In the elderly, the body and its immunity are not as strong as they used to be, which leads to an increased risk of COPD and other health infections and conditions.
The lungs lose their elasticity and the respiratory muscles weaken with age making breathing and the exchange of gases less efficient.
Another cause of COPD in the elderly is that certain changes take place in the nervous system, which makes coughing and clearing the mucus from the lungs less effective.
Mucus can accumulate in the lungs over time. It then becomes a target for infection to set in.
Genetic causes of COPD in young adults
As stated above, COPD symptoms usually appear after the age of 35 to 40 years. However, you do see the symptoms in young adults below 30 to 35 years though not so commonly. The cause of COPD in such young adults is usually a genetic predisposition.
This genetic reason can also contribute to a great extent in other age groups. There is an Alpha-1 Antitrypsin protein in our bloodstream, which is produced in the liver.
Some of us have a deficiency of this protein in the blood because of genetic factors. Due to this deficiency, white blood cells cause damage to the lungs. Such people are at a high risk of developing Alpha-1 Antitrypsin deficiency (AATD) related COPD and can suffer from it even if they have never smoked or exposed to other causes and risk factors.
Many people with this genetic disorder do not know that they have this genetic defect. It is diagnosed only after they develop COPD and are investigated.
It is estimated that about 100,000 Americans have AATD.
Under nutrition is an important risk factor in patients with COPD in causing flare-ups, poor prognosis and a deteriorated quality of life (QOL). Studies have indicated that deficiencies of certain vitamins such as vitamin D and C and other nutrients are commonly associated with COPD patients.
Improving on these deficiencies has had a beneficial effect vis-à-vis the symptoms, the flare-ups and the quality of life.
In people who have never smoked, the prevalence of COPD is found to be 25% to 45%. Other causes and risk factors besides smoking, mentioned above, contribute to this large incidence.