Chronic respiratory disease (CRD) is an umbrella term for diseases that prevent the lungs from working correctly, often affecting the airways, lung tissue, or lung circulation.¹ Environmental and/or genetic factors can increase the risk of developing a CRD.² Since most CRDs are incurable, the goal of treatment is to alleviate symptoms, prevent further lung damage, and improve quality of life. This article reviews several types of CRDs. 

Asthma (click here to access full article on asthma)

Bronchiectasis

Bronchiectasis is a condition in which the walls of the airways widen, often due to scarring or inflammation, and thus cannot clear out mucus. This mucus build-up can lead to bacterial growth and infection. Symptoms include persistent cough, coughing up large amounts of mucus, wheezing, fatigue, and thickening of the skin under the nails (clubbing).^3,4 Bronchiectasis can be caused by lung infections, disorders of the cilia, constantly inhaling food or liquids into the lungs, airway blockage, and other CRDs.^3,4 About half of all cases of bronchiectasis in the US are due to cystic fibrosis. Treatment methods include medications (e.g., antibiotics, inhaled steroids, bronchodilators, mucus thinners), chest physical therapy, and drinking enough water, which can prevent mucus from thickening.³

Chronic Obstructive Pulmonary Disease (COPD)

COPD is a group of progressive diseases characterized by inhibited airflow and breathing-related problems. COPD affects about 6.4 percent of individuals in the US and was the fourth leading cause of death in 2018.⁵ Most cases of COPD involve emphysema, in which air sacs and the walls between them are damaged and become less elastic, and chronic bronchitis, in which constant irritation and inflammation of the airways leads to swelling and overproduction of mucus.⁶ Symptoms include shortness of breath, persistent cough, coughing up large amounts of mucus, difficulty taking deep breaths, and making a whistling sound when breathing.^5,6 Comorbidities, such as cardiovascular disease and arthritis, are prevalent in those with COPD.^5,7 Smoking is one of the leading causes of COPD,⁶ and other risk factors include pollution, occupational exposures, respiratory infections, history of asthma, and alpha-1 antitrypsin deficiency. Quitting smoking and avoiding secondhand smoke are important for COPD prevention, as well as treatment. Other treatments include medication (e.g., bronchodilators, anti-inflammatory agents), pulmonary rehabilitation, pneumococcal pneumonia and influenza vaccination, oxygen therapy, and, in severe cases, surgery.^5–7 

Cystic Fibrosis

Cystic fibrosis is an inherited disorder that alters mucus production. Normal mucus is slippery and thin, but in cystic fibrosis, mucus is thick and sticky. Therefore, instead of acting as a lubricant, mucus blocks ducts and passageways in the body, particularly the lungs and pancreas.⁸ Respiratory symptoms include coughing up mucus, persistent cough, wheezing, recurring lung infections or chest colds, excess salt in sweat, and frequent sinus infections. Treatment aims to slow disease progression and improve quality of life.^9,10 Medications targeting gene mutations, other medications (e.g., antibiotics, anti-inflammatory agents, bronchodilators, mucus thinners), chest physical therapy, pulmonary rehabilitation, oxygen therapy, and nasal and sinus surgery can be used to treat cystic fibrosis.¹⁰

Interstitial Lung Disease (ILD)

Over 200 types of lung disorders fall under ILD.⁹ ILD causes scarring, or fibrosis, in the interstitium, the tissue surrounding air sacs. Fibrosis stiffens the interstitium, making it difficult to breathe and reducing the amount of oxygen that can get into the body. Causes of ILD include autoimmune diseases (e.g., sarcoidosis, rheumatoid arthritis, lupus), hypersensitivity pneumonitis (i.e., lung inflammation due to exposure to harmful foreign substances, including mold, dust, and fungus), breathing in other hazardous materials (e.g., asbestos [asbestosis], silica dust, coal dust, or cotton dust), certain medications, chest radiation therapy, and infection or partial recovery from certain diseases, including COVID-19. However, in many cases, such as with idiopathic pulmonary fibrosis, the cause of ILD is unknown. Shortness of breath that worsens over time is the most common symptom, and others include dry cough, fatigue, chest discomfort, and weight loss; advanced cases can result in clubbing, low blood oxygen, and high blood pressure.^11,15 Treatment options depend on the underlying cause and disease severity; for example, those with an autoimmune disorder can take certain medications to suppress the immune system and alleviate swelling in the lungs.¹⁵ Other treatment options include corticosteroid use, pulmonary rehabilitation, and oxygen therapy.^11,15

Obstructive sleep apnea (OSA)

OSA involves episodes of complete or partial collapse of the upper airway, accompanied by decrease in oxygen saturation or arousal from sleep. The prevalence of OSA in the US has increased over the years, and risk factors include male sex, older age, obesity, and craniofacial and upper airway abnormalities (e.g., undeveloped jaw, swollen tonsils).^13,14 OSA has been associated with other medical conditions, such as congestive heart failure, atrial fibrillation, obesity hypoventilation syndrome, asthma, COPD, ILD, and pulmonary hypertension.^13–15 Sleep fragmentation results in fatigue and, in individuals with another CRD, can exacerbate existing symptoms and further decrease quality of life.¹⁵ Additional symptoms include snoring, excessive daytime sleepiness, choking or gasping during sleep, interrupted breathing while sleeping, and morning headaches.^13,14 Treatment options include avoiding alcohol and drugs that might worsen OSA (e.g., opiates, sedatives, some antidepressants), treatment of comorbid disorders, positional therapy, continuous positive airway pressure (CPAP) therapy, use of custom-fitted oral appliances, and surgery.¹³

Pulmonary Hypertension

Distinct from systemic hypertension, which affects the whole body, pulmonary hypertension occurs when there is high blood pressure in the arteries of the lungs. The arteries narrow, and the right side of the heart must work harder to pump blood.^9,16,17 CRDs, autoimmune diseases that damage the lungs (e.g., scleroderma, rheumatoid arthritis), heart disease, heart failure, chronic low blood oxygen levels, birth defects of the heart, pulmonary embolism, and some medications (e.g., appetite suppressants) can cause pulmonary hypertension.^9,16 Shortness of breath is the most prevalent symptom, and others include fatigue, lightheadedness, chest pain, swelling of the ankles and legs, and heart palpitations.^16,17 Underlying medical conditions should be addressed when treating pulmonary hypertension. Various types of oral, intravenous, and inhaled medications, as well as oxygen therapy, blood thinners, diuretics, and digoxin, can be utilized to treat pulmonary hypertension.^16,18 Individuals taking blood thinners should consult with a physician before taking nonsteroidal anti-inflammatory drugs (NSAIDs). People with pulmonary hypertension should avoid over-the-counter decongestants and medications that contain stimulants and consult with a physician before taking any herbal therapies, as they can lead to complications when taken with certain medications.¹⁸

Editor’s note

Consult with a healthcare professional if you experience symptoms related to a CRD.

SOURCES

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