Chronic Obstructive Pulmonary Disease (COPD) in Dogs: Signs and Symptoms

Chronic Obstructive Pulmonary Disease (COPD) is a term used to describe a progressive inflammatory respiratory condition that restricts airflow from the lungs. 

The disease occurs after dog chronic bronchitis due to numerous bacterial, viral, fungal, and immune-mediated diseases. 

Bronchitis in dogs is caused by diseases such as kennel cough, heart disease, bacterial pneumonia, canine distemper, canine herpesvirus, and chronic allergies. 

The signs and symptoms of COPD in dogs are coughing, wheezing, exercise intolerance, and fainting. Chronic bronchitis dogs life expectancy depends on the severity. 

COPD for dogs that have had early diagnosis and treatment are able to have normal life expectancy. Dogs with prolonged, untreated COPD have severe lung tissue damage that has a poor prognosis. 

What is COPD in Dogs?

COPD in dogs is Chronic Obstructive Pulmonary Disease, a progressive and chronic respiratory condition. COPD is linked to chronic bronchitis and inflammation of the bronchial lining. 

The bronchi are the two main branches that serve as pathways from the trachea to the lungs. The disease is multifactorial in cause but is exacerbated by persistent exposure to environmental triggers such as dust, pollen, cigarettes, and strong chemicals. 

How do Dogs Get COPD?

Dogs get COPD when they contract chronic bronchitis, which is inflammation of the tissue that lines the bronchi. The lower airway, specifically the alveoli inside the lungs, is unable to receive oxygen, leading to respiratory distress. 

There is no single cause for chronic bronchitis and subsequent COPD, but environmental irritants and chronic infection are linked to the disease. There is “growing evidence for genetic risk factors for COPD: early familial aggregation and linkage analysis studies strongly suggested genetic contributions to COPD” in humans, according to Hardin et al. in the study entitled “Chronic Obstructive Pulmonary Disease Genetics: A Review of the Past and a Look Into the Future,” 2014. Dogs share respiratory similarities with humans, so genetic predisposition to COPD is a distinct possibility.

How is COPD Compared to Other Respiratory Problems?

COPD is a more progressive and chronic term used for dogs with long-term respiratory issues compared to other respiratory problems. Dogs with COPD develop coughs that last for several months and do not respond to conventional medications. 

Other respiratory diseases initially present with comparable respiratory signs and are acute or peracute in duration. The common diseases are self-limiting, respond to medication, and are preventable with vaccination. 

COPD as a respiratory problem develops as a consequence of prolonged bronchial inflammation, blocking the airways and resulting in bronchiectasis or pulmonary fibrosis, which is irreversible and progressive. 

What are the Common Causes of Canine COPD?

The common causes of canine COPD are listed below.

• Environmental Irritants: Inhalation of airborne pollutants is dogs' most probable cause of COPD. Cigarette smoke, exhaust smoke, strong chemicals, and dust are common airborne triggers that cause bronchitis. COPD in humans is generally linked to cigarette smoking.
• Chronic Tracheobronchitis: Diseases like kennel cough cause tracheobronchitis. The pathogens induce respiratory changes by causing tracheobronchial inflammation. Tracheobronchitis leaves the bronchi susceptible to chronic inflammation and COPD when left untreated.
• Poor Immunity: Dogs with poor immune defenses are more prone to catching diseases. Secondary complications occur if the dog’s immune system is compromised. The weakened respiratory system leads to COPD.
• Age-related Changes: Older dogs have been reported to be most affected by COPD. Weakened immune systems and age-related weaknesses of the different organs are factors to consider that predispose older dogs to develop COPD.
• History of Respiratory Disease: Dogs with repetitive respiratory infections are more prone to developing COPD. Each disease process affects the integrity and defenses of the respiratory system, making the dog more likely to develop COPD. 

Does COPD cause canine pneumonia?

No, COPD does not cause canine pneumonia. Dogs with COPD have a higher chance of developing pneumonia as a secondary complication. Pneumonia is the inflammation and infection of the alveoli inside the lungs. 

Severe lung tissue damage from COPD leads to bronchiectasis or the widening of the lungs' airways. The condition leads to a build-up of excess mucus that makes the lungs vulnerable to infection and canine pneumonia. 

Does exposure to smoke or pollutants increase the risk of COPD in dogs?

Yes, exposure to smoke or pollutants does increase the risk of COPD in dogs. Exposure to airborne irritants is one of the most widely believed causes of COPD in dogs. Persistent inhalation of smoke, dust, chemicals, cigarettes, and toxic fumes causes airway irritation. A dog that inhales these pollutants every day is more susceptible to COPD. 

How does age affect the likelihood of a dog developing COPD?

Age affects the likelihood of a dog developing COPD due to immune system maturity. Young puppies and older dogs have weaker immune defenses as an age-related consequence. 

Puppies are highly susceptible to common respiratory diseases after the maternal antibody titer has waned after several weeks. Dogs without proper vaccination are likely to contract respiratory diseases that damage the respiratory system, depending on the severity. 

Older dogs have poorer immune systems due to senescence, are prone to infections that cause bronchitis, and are slower to recover. 

What are the early signs that a dog might be developing COPD?

The early signs that a dog might be developing COPD are listed below.

• Persistent Dry Cough: The most common sign of COPD is coughing. COPD is progressive and severely damaging to the bronchi and lung tissue. Persistent bronchitis produces increased mucosal discharge, which is evidenced by productive coughing. COPD coughing lasts several weeks to months and does not respond to conventional medication using antibiotics. 
• Lethargy: Dogs with COPD have lower energy levels because they tire quickly. Daily activities become shortened, causing more strain on the dog. The dog becomes less active and has a decreased appetite due to the discomfort of COPD. 
• Exercise Intolerance: COPD affects the proper oxygenation of tissues needed during exercise. Walking and running are no longer tolerated well by dogs with COPD. Sudden and short-term fainting (syncope) is an outcome when a dog with COPD exerts too much effort. 
• Shortness of Breath: Dogs with COPD have an increased respiratory rate and are dyspneic. Shortness of breath is one of the most noticeable dog lung disease symptoms. The increased rate is due to the increased respiratory effort needed to provide oxygen circulation. The dog pants aggressively to breathe better.
• Runny Eyes and Nose: Runny eyes and nose are visible in early COPD as the dog has bronchitis. The discharge is from increased mucus production and inflammation. Some dogs get epiphora, evidenced by a wet patch underneath the eye. 

What are Dog COPD Symptoms?

The main dog COPD symptoms are listed below.

• Long-Term Cough: Coughing from COPD lasts several weeks or months. The coughing is unresponsive to traditional medication with antibiotics or antitussives. COPD is progressive and severely damaging to the bronchi and lung tissue, which makes the cough worse if left untreated. 
• Sudden Fainting: A sudden short-term lack of consciousness preceding a stressful event or exercise is a classic sign of syncope. Syncope occurs when the brain does not receive sufficient oxygen. COPD severely impairs blood oxygenation, so the brain is unable to get enough air to function correctly. 
• Cyanosis: The pink coloration of the conjunctiva and mucous membranes is due to the circulation of oxygenated blood. The gums and tongue become greyish-blue when tissues are poorly oxygenated. COPD affects the ability of the alveoli to incorporate oxygen into the blood and circulate it to the body. 
• Depression: COPD is slowly progressive and chronic. Pulmonary fibrosis is an especially uncomfortable and irreversible change in lung tissue. The lungs start to form scar tissue and fibrosis, reducing viable tissue for oxygen exchange. Dogs with COPD become less active, have low energy, and have difficulty doing daily activities. 
• Wheezing: Inflamed airways during COPD cause increased respiratory effort. A wheezing sound is evidence of respiratory distress due to poor oxygen circulation. COPD blocks the airway and affects airflow, which causes the wheezing sound. 

How is COPD in Dogs Diagnosed?

COPD is diagnosed using laboratory examination and evaluation of history and clinical signs. Auscultation is an important step of physical activity that checks lung and heart sounds. 

Lung crackles and wheezes are observable in dogs with COPD. Heart rate and blood pressure sometimes decrease, and cardiac arrhythmia is noticeable. Diagnostic tests are performed to confirm COPD by ruling out other diseases. 

A complete hematological screening rules out anemia-causing diseases and parasites. Thoracic radiography helps screen the extent of heart and lung disease. 

Additional magnetic resonance imaging or computed tomography imaging is utilized for better visualization. A bronchoscopy and bronchoalveolar lavage is done to visualize the bronchial lining and acquire a sample of fluid aspirated from the lungs. 

The sample is sent to the laboratory for culturing and identification.

Can COPD in Dogs be Prevented with Vaccines?

No, COPD in dogs cannot be prevented with vaccines. Common infections such as canine adenovirus type 2, canine distemper, and Bordetella bronchiseptica are preventable through vaccination. COPD is a consequence of persistent bronchitis linked to inhalation of environmental pollutants. Proper prevention and environmental control prevent COPD. 

What are the Stages of COPD in Dogs?

The stages of COPD in dogs are categorized into early and late stages. The early stages show the upper airway and bronchi becoming markedly inflamed. Persistent inflammation causes a blockage, leading to compensatory lung changes as weeks pass. 

Bronchiectasis results from compensatory dilation to help the dog circulate air better. Pulmonary fibrosis occurs in later stages. Pneumonia results from chronic bronchial inflammation, which predisposes the dog to alveolar infection.

How Does COPD Affect Dogs?

COPD affects dogs by reducing the oxygenation of tissues. The body is unable to receive adequate circulating oxygenated blood since the lungs are dysfunctional. Alveolar oxygen diffusion to the blood and airway inflammation contributes to the hypoxia of dogs with COPD. The disease causes chronic coughing and difficulty breathing. Daily activities become difficult, which causes episodes of lack of consciousness. 

What are the Risks of Long-term COPD if not Treated?

The risks of long-term untreated COPD are listed below.

• Pneumonia: Pneumonia is the inflammation or infection of the alveolar tissue inside the lungs. Severe lung tissue damage from COPD leads to bronchiectasis, or the widening of the lungs' airways. The condition causes excess mucus build-up, making the lungs more vulnerable to infection and pneumonia. 
• Pulmonary fibrosis: Pulmonary fibrosis is a consequence of chronic bronchitis, wherein the lung tissue starts to form scar tissue. COPD triggers scar tissue formation, which thickens, damages, and stiffens the alveoli. The result is poor oxygen diffusion and subsequent poor oxygen perfusion of the body. 
• Bronchiectasis: Chronic bronchitis causes the bronchial tissue to inflame and produce more mucus. The bronchi start to compensate by widening the airways of the lungs. The condition leads to excess mucus build-up, making the lungs more vulnerable to infection and canine pneumonia. 
• Syncope: Syncope is the sudden loss of consciousness due to inadequate oxygen perfusion to the brain. The brain becomes hypoxic due to the lack of proper oxygen perfusion, causing the dog to lose consciousness. The fainting is short and occurs suddenly, usually after stressful conditions or physical activity when the body demands more oxygen. 
• Heart Disease: Severe COPD causes heart failure in the right ventricular chamber. COPD is able to cause congestive heart failure as a consequence of hemodynamic insufficiency. The heart has its compensatory mechanisms when oxygen perfusion is low. The heart starts to work overtime, which causes congestive heart failure that manifests as ascites.

What complications can arise from COPD in dogs?

The complications that can arise from COPD in dogs are listed below.

• Permanent Lung Scarring: The lungs become permanently scarred and fibrotic. The result is alveolar stiffness, which prevents the lungs from properly diffusing oxygen. Dogs with lung scarring have poor prognoses and require lifetime oxygen therapy. 
• Emphysema: The inner walls of the alveoli rupture, reducing the surface area of the lungs. Reduced surface area means that oxygen's ability to properly become incorporated into the bloodstream is significantly poorer. Dogs with emphysema have a poor prognosis.
• Chronic pneumonia: COPD predisposes the dog to bacterial infections. The infections reach as far as the alveolar tissue, which becomes filled with pus. The result is a productive and painful cough with chest tightness.
• Hypoxia: Inadequate tissue perfusion leads to the dog becoming pale and bluish-grey and having poor tolerance for even the slightest activity. Sudden temperature changes make walking, playing, and running no longer an option and become life-threatening for some dogs with COPD. 
• Congestive Heart Failure (CHF): COPD overexerts the heart when trying to restore proper oxygen perfusion. The right side of the heart, which is the chamber directly before the blood reaches the lungs, enlarges and causes edematous changes due to regurgitation. A dog with CHF due to COPD develops ascites, which complicates the condition further. 

Is COPD in dogs a reversible condition?

No, COPD in dogs is not a reversible condition. There is no cure to return the lungs to normal once the structures of the airway and lungs are damaged. Proactive management is performed to slow down the progression of the disease. Consult a veterinarian to learn how to reduce the symptoms associated with COPD. 

Is COPD Fatal in Dogs?

Yes, COPD is fatal in dogs. The disease becomes a cascade of events that eventually lead to death when left unnoticed and untreated once it is contracted. The dog dies of hypoxic changes that lead to heart and lung failure, which are vital organs of the body. Managing COPD involves early detection so that progress is slowed down with medication and proper management. 

Can CBD Oil Help Dogs with COPD from Getting Worse?

No, COPD cannot help dogs with COPD from getting worse. COPD is progressive and incurable. Dog CBD oil helps manage signs of pain, anxiety, and discomfort but cannot stop COPD from progressing. CBD is used to help relax and relieve the dog from painful symptoms by activating the endocannabinoid receptors.