COPD & Exercise

According to the National Heart, Lung, and Blood Institute, COPD makes it hard for individuals to breathe normally. Chronic obstructive pulmonary disease often gets worse with time (COPD).

An estimated 328 million people worldwide struggle with COPD (Quaderi, 2018). The main cause of COPD is cigarette smoking. However, some individuals are born with a genetic condition called alpha-1 antitrypsin deficiency. Having low amounts of the AAT protein in the blood can predispose individuals who are exposed to smoke and other irritants to COPD.

Many individuals in the early stages of COPD may not realize they have the disease. Gylys and Wedding (2013) explain that COPD is often a combination of three major pulmonary disorders: asthma, chronic bronchitis, and emphysema. 

Emphysema is the destruction of alveolar walls. The lungs then lose their normal elasticity and may struggle to properly exhale oxygen. Chronic bronchitis causes the airways to become clogged with excessive mucus. Those diagnosed with COPD often have combinations of these diseases to varying degrees.

SIGNS & SYMPTOMS

Principal signs and symptoms include shortness of breath (SOB), difficulty breathing during physical activity (dyspnea), coughing, and mucus discharged from the respiratory tract (Venes, 2017). Because COPD is a combination of several diseases, individuals may experience some or all of these symptoms daily or sporadically. 

The chronic cough with excessive mucus indicates chronic bronchitis. The airways often become more clogged over time. Initially, patients may exhibit little to no symptoms due to the slow progression of the disease.

CAUSES

Most people diagnosed with COPD are or have been smokers. Tobacco smoke is toxic and damages the lungs. Tønnesen (2013) teaches that individuals who quit smoking have higher survival rates and lung function compared to individuals who keep smoking. Alternative causes include second-hand smoke exposure, environmental pollution, dust, or chemicals.

PATHOPHYSIOLOGY

COPD is a pulmonary disease that causes obstruction of the airways to and from the lungs.

Thousands of small tubes called bronchioles lead to little air sacs called alveoli. Blood vessels called capillaries surround the alveoli. When air travels through the tubes to the alveoli, oxygen is delivered to the blood via the capillaries. Simultaneously, carbon dioxide from the blood is passed to the alveoli. The lungs help distribute oxygen to all vital organs and eliminate waste (COPD).

Kim (2017) described the two pathologic process that occur as a result of COPD:

1. Narrowing of the airways or bronchioles
2. Destruction of the alveoli and alveolar ducts themselves

These two processes are a result of chronic inflammation of the lungs due to exposure from noxious gases and particles in the air.

DIAGNOSIS

Lange et al. (2016) explain that COPD should be tested for any individual with chronic coughs, shortness of breath, or a history of cigarette smoking. Spirometry is used to calculate the degree of persistent airflow limitation to the lungs. Chest x rays, CT scans, and sputum analysis are used in addition to spirometry.

The clinical definition of persistent airflow limitation is FEV1/FVC <0.7. In layman's terms, FEV1/FVC is how much a person can exhale measured in the first second of expiration. COPD causes over-inflation of the lungs and lowers the amount of airflow exhaled.

However, this definition has been shown to overestimate the presence of the disease in the old and underestimate in the young (Lang et al., 2016). Because of this, the GOLD standards have recently been changed to include the following steps for diagnosing COPD:

• Symptoms
• Degree of airflow limitation
• Risk of exacerbation
• Comorbidities

These four symptoms are combined and patients are put into one of four categories based on scores: mild, moderate, severe, and very severe.

MANAGEMENT

At least four methods are commonly prescribed to treat COPD: medication, exercise, smoking cessation, and respiratory therapy.

Medications used during exacerbations include albuterol to raise oxygen levels, antibiotics to combat excessive mucus production, and corticosteroids to reduce inflammation. Medications used for chronic disease management include tiotropium (bronchodilator) to widen airways and increase airflow and formoterol.

The ACSM states that exercise is an effectual intervention that “lessens the development of functional impairment in all patients with COPD regardless of disease severity” (ACSM, 2013, p. 334-335). Exercise helps build the muscular and cardiovascular systems, which in turn relieves pressure on the pulmonary system (ATS, 1999).

ACSM recommendations for exercise prescription:

• Frequency: Minimum 3-5 days per week
• Intensity: Vigorous (60-80% peak) for greater physiological improvement, light (30-40% peak) for improvements in quality of life and symptoms
• Time: Adjusted to match individual response and tolerance
• Type: Primarily walking/cycling along with resistance training (especially the upper body)

EPIDEMIOLOGY

COPD is a noncommunicable disease, meaning that it cannot be passed from one person to another. It affects 12 million Americans and an estimated additional 12 million who are not diagnosed. The prognosis for COPD can be depressing. 

There is no known cure for the disease, and the lung function cannot be fully restored after it is damaged. Patients move through 3 phases of the disease as COPD progresses over time: lung function ≥ 50%, lung function 35-49% with substantial impact on health, lung function <35% with a major impact on health (Tamparo & Lewis, 2011). 

Prevention includes quitting smoking, early treatment, and regular exams from a pulmonary specialist.

ETYMOLOGY/HISTORY

The history of COPD and modern treatment of the disease began approximately 200 years ago. Petty (2006) observes that COPD is the fourth most common cause of death currently in the United States. Additionally, it is the only disease among the top five diseases that is currently increasing in mortality. The NHLBI (2003) estimates that COPD results in a $32.1 billion loss to the economy.

But how did we get to this point? Bonet (1679) and Morgani (1769) were some of the earliest scholars to describe aspects of the disease. They observed “voluminous lungs” and 19 cases of swollen lungs respectively.

Badham (1814) began the clinical conversation for chronic bronchitis when he observed patients with excessive mucus and persistent coughing. Laënnec (1821), inventor of the stethoscope, described hyperinflated lungs which is a sign of emphysema in both the living and dead during a time when smoking was uncommon.

Hutchinson (1846) created the spirometer to initially detect COPD. This tool measures lung function and the amount of air inhaled and exhaled at rest. Finally, Tiffeneau and Pinelli (1947) improved the instrument by adding a way to measure timed air capacity and speed of inhalation/exhalation. Barach and Bickerman (1956) helped create the first clinical textbook on COPD, emphysema, and asthma. Their work contributed to how we define and treat COPD to this day.

SOURCES

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