If you have been diagnosed with chronic obstructive pulmonary disease (COPD), your immediate concern (and your doctor’s) should be to determine how much your disease has progressed or at what stage of COPD your disease has currently advanced to.
The COPD disease has been classified into 4 stages, from mild to very severe, using the guidelines and criteria laid down by the Global Initiative for Chronic Obstructive Lung Disease (GOLD). These are primarily based on the fev1/fvc ratio obtained through the spirometry test.
This grading helps to determine how much your disease has advanced in terms of severity, the treatment plan, the prognosis and the final outcome relating to mortality, that is the life expectancy of the COPD patient.
COPD is a disease of the lungs in which the pathological changes of both chronic bronchitis and emphysema are present. You should read about the pathophysiological changes and the alarming statistics to know how COPD damages your lungs and kills.
Bronchitis is an infection of the bronchi (airways). It could be viral where the bacterial infection also may set in. You call bronchitis chronic when this condition occurs for a long time or keeps recurring. Cigarette smoking or constant exposure to pollution can make this condition chronic.
Its symptoms include a cough that brings up thickened, discolored mucus. As the condition worsens, the patient experiences wheezing, chest pain, and shortness of breath.
Emphysema is an irreversible condition in which the air sacs called alveoli are damaged permanently. The alveoli are present at the end of the bronchioles (end small airways) in which the exchange of gases takes place.
As the condition progresses, more and more alveoli get damaged diminishing the surfaces for gas exchange. The respiratory function reduces and breathlessness progresses.
The COPD stages or grades go on progressing and its symptoms, which are those of chronic bronchitis and emphysema combined, increase in severity.
Why is COPD staging important?
The identification of the COPD stage will tell you and your doctor how much your lung is damaged, what will be the prognosis, and help your doctor to choose the right plan of treatment.
For example, the staging will help the patient and the doctor in the following ways:
- Helps the patient with COPD understand his disease better
- Makes it easier for the doctor to plan the treatment and advice recommendations in a better fashion
- Helps to predict life expectancy
- Forewarns the patient to plan for his future
What are the GOLD criteria for grading COPD?
The Global Initiative for Chronic Obstructive Lung Disease (GOLD) grading system now classifies COPD into four grades according to the airflow limitation and severity of the symptoms.
Formerly, pulmonologists (lung specialists) used the four-grade classification based on the results of the patient obtained through a test called spirometry. This test is carried out in the doctor’s office and the results are obtained immediately.
Spirometry measures the amount of air you can blow out and how fast you blow it out. The results give an indication of your lung capacity, airflow limitation, and lung function. The lower your score on the spirometry machine, the more severe is your lung condition.
This test is also called the pulmonary function test or the lung function test. It is not just used for COPD but also to diagnose other lung conditions that affect breathing, such as asthma.
Nowadays, the criteria have been modified to fit the new guidelines recommended by the Global Initiative for Chronic Obstructive Lung Disease (GOLD).
The old GOLD criteria, first published in 2001 and later updated in 2007 classified COPD according to the results obtained from the spirometry test alone (FEV1).
GOLD, later after much research, published new standards for staging COPD in 2011. These new guidelines now take into consideration the symptoms and exacerbation (flare-ups of symptoms) history in addition to the degree of airflow obstruction for classifying patients with spirometry.
Spirometry, therefore, still forms the main assessment tool in the staging of COPD.
The new GOLD guidelines released in early 2011 recommend that in addition to the spirometry results, the severity and frequency of the symptoms and exacerbations be also considered to grade the stage of COPD. This now gives a better idea of the severity of the disease.
Spirometry result interpretation
Forced vital capacity (FVC), is the amount of air that you can forcibly exhale from the lungs after taking the deepest breath possible.
Forced expiratory volume (FEV1) is the amount of air you can blow out with full force in one second.
You measure both these parameters in liters.
Normal values
FEV1 – 80% to 120%
FVC – 80% to 120%
Absolute FEV1 /FVC ratio – 80%
Understanding the four COPD stages by spirometry (FEV1) and symptoms
The gold staging begins with the early stages where the patient is comfortable without any suspicion of having developed COPD.
It is the second stage where he may seek medical help due to noticeable symptoms. The advanced stages will need aggressive treatment and lifestyle discipline.
Stage 1 of Mild COPD
This is the beginning stage indicating the onset of the COPD disease with mild airflow limitation. Spirometry results in this stage will show normal results of FEV1 of 80% or more. Chronic cough with sputum may or may not be present. There is nothing in this stage to remotely suggest the onset of COPD. The patient rarely goes to the doctor at this stage.
If you are lucky and diagnosed, it is necessary at this stage to give up smoking if you are a smoker and avoid other causes and risk factors. This will improve life expectancy.
Treatment consists of short-acting bronchodilators.
Stages 2, 3, and 4 are the advanced stages of COPD, where the pathological changes progress with further deterioration of the symptoms.
Stage 2 of Moderate COPD
As the disease progresses to the second stage, the airflow limitation worsens and the patient along with cough and mucus starts experiencing breathlessness upon exertion, which he did not earlier.
He may have to stop to catch his breath. He is not able to catch up with people with whom he walked earlier. Spirometry results show an FEV1 of 50% to 79%. This is the stage when the patient feels the need for medical help.
Emphysema, which is also present, progresses and bronchial obstruction and airflow limitation go on deteriorating.
The patient may develop a bluish tint to the lips or skin from low oxygen levels in the blood.
It is at this stage that the patient starts to experience exacerbations or flare-ups. These are nothing but a sudden worsening of the symptoms.
Depression may set in because the patient is unable to put in physical activity as before and prefers to stay indoors.
Treatment advised is
- Short-acting bronchodilators
- Long-acting bronchodilators
- Pulmonary rehabilitation
Stage 3 of Severe COPD
In stage 3 of COPD, FEV1 shows results between 30% and 49%, indicating a further worsened airflow limitation. COPD has advanced significantly as seen by the symptoms, which include an increase in cough, a change in color of the sputum, and the onset of repeated exacerbations.
Exercise tolerance reduces and the patient tends to fatigue sooner than usual. Emphysema has become severe.
Treatment is
- to carry forward treatment as in stage 2
- in addition, inhaled steroids are advised for flare-ups
- If infection has set in, antibiotics will be necessary
- Long-term oxygen therapy will be advised
- Doctors may consider surgical intervention.
End Stage 4 of very severe COPD
Stage 4 is often referred to as the final or the end stage of COPD. The disease has progressed to an ultimate level beyond which there is no further room for worsening.
The airflow limitation has worsened to the point that chronic respiratory failure sets in. FEV1 falls below 30%. You become breathless even doing your daily household chores like wearing your pants. You will need supplemental oxygen to breathe. Quality of life significantly deteriorates.
Coughing frequency and severity increase, sleep is compromised and edema can set in with swelling of the ankles and feet due to poor circulation of the blood.
Respiratory failure can cause complications that affect the heart such as cor pulmonale. This can be fatal.
The severity and the frequency of exacerbations (flare-up of symptoms) increase to the point of being life-threatening.
Symptoms of exacerbations include a rapid heart rate, cough accompanied by excessive mucus production that can be yellow or green or bloody, a feeling of tightening in the chest, wheezing, and shortness of breath at rest, which worsens on exertion. Medicines may not give relief.
More than half of the patients who have advanced to stage 4 with FEV1 below 30% will not live beyond four years.
While people in stage 4 can be very sick, you will find quite a few who still enjoy an active and quality life. They are the ones who eat right, exercise regularly, take their medications religiously, and generally take very good care of themselves.
Prognosis: How does COPD worsen?
The fact remains that people with COPD have a decreased lifespan as compared to people without COPD. The risk of mortality is also higher and this risk increases as the stage and the severity of the disease progresses.
How this happens:
- As the disease advances causing more lung tissue damage, respiratory function starts failing.
- Airway obstruction increases causing more air limitation.
- The exchange of gases (oxygen against carbon dioxide) suffers leading to the retention of more carbon dioxide in the blood.
- Organs like the heart do not get sufficient oxygen through the blood.
- Their function starts deteriorating and serious complications like cor pulmonale set in. This is a condition that causes the right side of the heart to fail and is typical of the primary disorder of the respiratory system.
Continued smoking in a patient with COPD makes the disease progress faster. Smoking cessation is, therefore, a must to improve life expectancy.
The life expectancy of COPD patients
COPD is associated with only a modest reduction in life expectancy for non-smoking people. But, the life expectancy is significantly reduced in past and current smokers.
According to the NHANES III Follow-up Study published in the International Journal of Chronic Obstructive Pulmonary Disease, COPD life expectancy stage-wise has been described.
In conclusion, the study states that
“COPD is associated with increased mortality and, thus, with reduced life expectancy. Those with stage 1 or 2 COPD lose at most a few years of life expectancy at age 65 compared with persons with no lung disease, in addition to any years lost due to smoking. But current smokers with stage 3 or 4 COPD lose about six years of life expectancy, in addition to the almost four years lost due to smoking”.
What can COPD patients die from? Causes
The major causes of death in a COPD patient can be due to either of the following conditions:
- Acute-on-chronic respiratory failure
- Cor pulmonale
- Respiratory tract infection not responding to treatment
- Pulmonary embolism
- Fatal arrhythmias (rapid and irregular beating of the heart)
- Lung cancer. Though COPD does not cause lung cancer directly, the conditions that develop over time make it conducive for cancer to develop in COPD patients who are or were long-time and heavy smokers.
COPD is the third largest cause of death worldwide after heart disease and cancer. The morbidity misery is high and can significantly lower the quality of life, which can make you go into depression. Take those proper steps to prevent COPD.