Chronic obstructive pulmonary disease (COPD) is a progressive lung disease that makes it difficult to breathe. There are two main types of COPD: chronic bronchitis and emphysema. Over time, people with COPD experience worsening breathlessness due to airway obstruction and lung damage.
While COPD itself can significantly impact daily life, the condition also leads to other complications that can be very serious. Understanding the potential complications of COPD is important for managing the disease and preventing severe outcomes.
Respiratory Infections
One of the most common and serious complications of COPD is respiratory infections. People with COPD are prone to lung infections for several reasons:
- The lungs are already inflamed and damaged, making it easier for bacteria or viruses to take hold.
- Thick mucus builds up in the lungs, creating an environment where germs can grow.
- The cilia (tiny hair-like structures) that normally sweep mucus out of the airways work less efficiently.
- Cough reflexes are impaired, so it’s harder to clear the lungs.
- Some of the medications used to treat COPD, like steroids, can suppress the immune system.
The most significant respiratory infections that affect people with COPD include:
Pneumonia
Pneumonia is an infection of the lungs that causes the air sacs (alveoli) to fill up with fluid or pus. Symptoms include fever, cough, fatigue, chills, shortness of breath, and chest pain with breathing or coughing. Pneumonia can be life-threatening for anyone, but even more so for people with COPD who already have compromised lung function. According to research, pneumonia accounts for about 25% of COPD-related hospitalizations and is a leading cause of death.
Bronchitis
Acute bronchitis occurs when the bronchial tubes (airways) become infected and inflamed, leading to coughing and excess mucus production. Chronic bronchitis is defined as a recurrent cough with mucus most days for at least 3 months a year, for 2 consecutive years. Many people with COPD have chronic bronchitis along with emphysema (this is known as chronic bronchitis with emphysema). Bronchitis flares can significantly worsen COPD symptoms.
Influenza
The flu virus attacks the respiratory system leading to fever, body aches, fatigue, cough, and congestion. For people with COPD who already have compromised lung function, the flu can be extremely dangerous. According to the Centers for Disease Control and Prevention (CDC), the flu contributes to the majority of COPD hospitalizations during flu season. People with COPD are also at high risk for secondary bacterial infections like pneumonia after getting the flu.
Respiratory Failure
Respiratory failure means that the respiratory system is failing and oxygen levels in the body are too low. People with COPD are at increased risk for two types of respiratory failure:
Chronic Respiratory Failure
This means that the lungs have lost some of their ability to exchange gases like oxygen and carbon dioxide. Breathing becomes inefficient. The main cause is the breakdown of lung tissue associated with emphysema. Low blood oxygen levels usually develop gradually.
Acute Respiratory Failure
This is a sudden, life-threatening situation where oxygen levels drop rapidly and carbon dioxide builds up. It may be triggered by a lung infection, blockage of the airways, Heart failure, or another event that acutely worsens lung function. Immediate treatment with oxygen therapy, medications, and possibly mechanical ventilation is required to prevent severe organ damage and death.
Over time, chronic respiratory failure can lead to complications like pulmonary hypertension, respiratory acidosis, and heart problems. Oxygen therapy and lung therapies can help support respiratory function, but respiratory failure is one of the most common causes of death associated with COPD.
Exacerbations
A COPD exacerbation refers to a sudden worsening of COPD symptoms like cough, mucus production, and breathlessness. Exacerbations are mainly triggered by lung infections, although air pollution and other factors can play a role. Severe exacerbations may require hospitalization.
Frequent exacerbations have many harmful effects, including:
- Accelerated loss of lung function
- Decreased quality of life
- Increased risk of death
- Higher healthcare costs
Research shows that people with frequent exacerbations (for example, 2 or more per year) have significantly faster disease progression. Severe exacerbations that require hospitalization are associated with increased mortality risk.
Preventing Exacerbations
While exacerbations cannot always be avoided, important prevention strategies include:
- Avoiding respiratory infections through flu and pneumonia vaccinations.
- Avoiding air pollution and irritants like smoke.
- Early treatment of respiratory infections before they trigger an exacerbation.
- Using prescribed inhalers correctly to control symptoms and prevent exacerbations.
- Participating in pulmonary rehabilitation to learn self-management skills.
Heart Disease
People with COPD are at higher risk for several forms of heart disease, including:
Coronary Artery Disease
Coronary artery disease (CAD) is the buildup of plaque in the heart’s arteries, which can lead to heart attack. According to research, people with COPD are 2-5 times more likely to develop CAD. The risk increases with the severity of COPD. Shared risk factors like smoking likely contribute to the link between COPD and CAD.
Heart Failure
Heart failure means the heart cannot pump enough blood and oxygen to meet the body’s needs. About 20-30% of people with COPD also have heart failure. COPD medications like beta-agonists may worsen heart failure in some people. On the other hand, COPD can make heart failure worse by restricting oxygen supply.
Atrial Fibrillation
Atrial fibrillation (AFib) is an irregular, rapid heartbeat. Low blood oxygen levels associated with COPD may increase the risk for AFib. People with COPD are also more likely to develop AFib after certain surgeries.
Pulmonary Hypertension
Pulmonary hypertension is high blood pressure in the arteries that supply the lungs. It develops when the arteries become narrowed or blocked. About 40% of people with severe COPD have pulmonary hypertension, which puts extra strain on the heart.
Managing heart disease is very important for people with COPD, since heart problems can aggravate lung symptoms. Treatment usually includes medications and lifestyle changes like quitting smoking and increasing exercise.
Lung Cancer
COPD is an independent risk factor for lung cancer. According to research, people with COPD are 2-4 times more likely to develop lung cancer compared to the general population. The risk is strongly associated with the severity of COPD – people with very severe COPD have the highest risk.
Shared risk factors like smoking are one reason for the link between COPD and lung cancer. But COPD-related inflammation in the lungs may also promote tumor growth. Early screening for lung cancer is recommended for people with COPD who are at high risk due to smoking history.
Weight Loss & Muscle Wasting
Unexplained weight loss and muscle wasting are common concerns in late-stage COPD. Multiple factors contribute to the problem:
- Increased work of breathing leads to excess calorie expenditure.
- Some medications like corticosteroids increase metabolism.
- Appetite may be reduced.
- COPD exacerbations can worsen nutritional status.
- Oxygen deprivation worsens muscle wasting.
Weight loss and muscle depletion, especially in the legs, negatively impact function and quality of life. Nutritional supplementation and exercise programs like pulmonary rehabilitation help counteract wasting.
Depression & Anxiety
Depression affects over 40% of people with severe COPD. Anxiety frequently co-occurs with depression. Some contributing factors include:
- Difficulty breathing and decreased activity lead to social isolation.
- Supplemental oxygen dependency affects self-image.
- Fear and panic accompany severe exacerbations or breathlessness.
- Steroid medications may worsen mood symptoms.
Evidence shows that COPD patients who have depression or anxiety have:
- More frequent exacerbations
- Higher healthcare utilization
- Impaired quality of life
- Increased mortality risk
Treatment through counseling, medications, and coping techniques can help manage mood symptoms that often accompany COPD.
Sleep Disorders
Up to 70% of people with COPD experience some form of disordered breathing during sleep, including:
Hypoxia
Low oxygen levels during sleep, especially during REM sleep when breathing irregularities occur.
Hypercapnia
Increased carbon dioxide levels during sleep, caused by hypoventilation.
Sleep Apnea
Interruptions in breathing during sleep, which reduce restfulness. Up to 1 in 4 people with COPD may have overlapping obstructive sleep apnea.
The combination of low oxygen, high carbon dioxide, and poor sleep quality caused by these disorders creates a number of problems:
- Daytime fatigue and sleepiness
- Cognitive dysfunction
- Worsening of heart failure
- Increased risk of exacerbations
Sleep studies and treatment with supplemental oxygen or CPAP during sleep help manage these risks.
Osteoporosis and Bone Fractures
People with COPD are at increased risk for the bone disease osteoporosis. Multiple factors are involved:
- Medications used to manage COPD, especially oral corticosteroids, have adverse effects on bone.
- Older age and low body weight predispose to bone loss.
- Reduced physical activity leads to increased bone loss.
- Systemic inflammation and reduced oxygenation may promote bone resorption.
Osteoporosis leads to an increased risk of bone fractures, especially in the hip and spine. Fractures cause significant disability and reduce quality of life. They may also increase mortality risk. Bone density screening and treatment with bone-strengthening medications help reduce fracture risk.
Conclusion
COPD is a complex disease that affects not only the lungs, but increases susceptibility to many other health conditions. Respiratory infections, lung cancer, heart disease, depression, sleep disorders, and osteoporosis all occur at higher rates among COPD patients.
Exacerbations or disease progression leading to acute or chronic respiratory failure are among the most immediate life-threatening complications. However, comorbidities like heart disease and lung cancer also significantly impact prognosis and survival.
Fortunately, many of these complications can be prevented or managed with COPD therapies, vaccinations, lifestyle modifications, and careful monitoring. This requires a comprehensive approach between various specialists and the patient to optimize well-being and minimize risks.