COPD-Bronchiectasis Overlap Syndrome - A Review

Introduction

In the widespread field of respiratory medicine, the interplay of chronic obstructive pulmonary disease (COPD) and bronchiectasis gives rise to a unique clinical condition, COPD-bronchiectasis overlap syndrome. This is particularly challenging for clinicians, and a multi-disciplined approach is necessary. COPD and bronchiectasis are two different respiratory disease conditions often seen together. The article aims to describe this syndrome and its management approaches.

What Is COPD Bronchiectasis Overlap Syndrome?

It is most commonly characterized by the existence of COPD and bronchiectasis, leading to a complicated course of disease and exacerbated symptoms, and is very challenging to treat. COPD and bronchiectasis share similar symptoms and are major diagnostic challenges. Recurrent exacerbations triggered by infections and common symptoms like cough with sputum are seen. The death rate is also high in case of overlap cases. COPD is seen as an obstruction of airflow associated with lung inflammation. Usually, it has a basis for cigarette smoking as a cause for it. Bronchiectasis is the presence of dilatation of airways, and on imaging, thickened walls are seen. The diagnosis is mostly based on its structure.

What Is Etiology and Pathophysiology?

Both COPD and bronchiectasis share risk factors. These include:

• Smoking: The most common factor and is considered a primary trigger agent.

• Environmental Exposures: Hazards, air pollutants, occupational exposure to chemicals, and inhalation.

• Infections: Microbial colonization of harmful agents like Streptococcus pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa.

• Inflammatory Cascade: Both these diseases arise from inflammation. Long-term exposure to irritants leads to increased inflammatory response.

• Genetics: A strong association was made between genetics and both these diseases.

The pathogenesis is structural changes occurring due to chronic inflammation, fibrosis, and increased mucus secretion. This leads to thickening of walls and greater chances of infections, which exacerbates the clinical manifestations of the diseases. Immune dysfunction is another preponderant cause of infections.

What Are the Clinical Features?

A comprehensive assessment of symptoms, lung function, and what factors exacerbate them should be performed. Clinically, this syndrome manifests as a complex combination of both COPD and bronchiectasis. It is essential to recognize the signs early and start management strategies.

• Persistent Cough: This may also be accompanied by sputum production. Cough in these individuals reflects increased secretion of mucus in the airways and an increased inflammatory state.

• Sputum: Sputum production is variable; it can be mucus-filled, pus-filled, or mixed. This difference is mainly because of differences in the degree of bacterial colonization.

• Difficulty Breathing: These individuals find breathing difficult, often during exercise or physical activity. This can be attributed to limited air due to the narrowing of airways and abnormalities seen in oxygen and carbon dioxide exchange.

• Wheezing: This is indicative of some form of obstruction seen in the airways. Patients also complain of feeling tightness in their chest.

• Hemoptysis: This is coughing up blood and is mainly associated with airway damage and malfunction.

• Increased Tiredness: When the overall lung health is deteriorating, there is an increased load on the lungs, and a compromise in physical function is seen.

• Malnutrition: The increased demand for breathing puts extra strain on the body, and therefore, these individuals frequently suffer from nutritional deficiencies and weight loss, further impacting their quality of life.

How Is This Disease Managed?

Diagnosing and managing requires a multidisciplinary approach. Treatments aim to reduce symptoms and exacerbations and help the patient in their daily life. Before embarking on any treatment modality, the patient has to be educated on self-management, particularly during exacerbations, and optimize the usage of inhalers or nebulizers with advanced techniques to best benefit from all treatment modalities.

Management recommendations include:

• It is crucial first to determine what the primary diagnosis is. This helps in treatment and follow-up.

• In cases where bronchiectasis is the primary diagnosis, fixed airflow is deemed a prognostic marker. Patients having this are considered to have a poor prognosis.

• Airway obstruction is generally considered a COPD pattern type.

• Although a tentative diagnosis can be made, further studies are needed to ascertain the diagnosis and figure out the disease progress pattern.

The various treatment approaches are :

1. Pharmacological Approaches

• Bronchodilators: Long-acting agents are used orally and as inhalers to help relieve bronchoconstriction and improve airflow.

• Corticosteroids: These are prescribed inhalers to reduce airway inflammation. Usually, a combination of medicines is used.

• Antibiotics: These are used to suppress growth or kill bacteria in case of infections.

• Mucolytics: Prescribed to mobilize mucus, helping in airway clearance.

• Immunizations: To reduce the risk of further infections, the patients are advised to take regular flu shots and other seasonal vaccinations.

2. Non-pharmacological Approaches

• Airway Clearance Techniques: Patients benefit from techniques such as postural drainage and vibratory and percussion devices to help clear secretions in the airways.

• Smoking Cessation: It is the main risk factor in COPD cases. By stopping this habit, it not only slows the progression of disease but also improves overall health.

• Balanced Diet: Addressing the nutritional demand and maintaining a healthy weight is important for overall well-being.

• Oxygen Therapy: In individuals who frequently face low oxygen saturation levels, it is imperative to prescribe long-term oxygen therapy.

• Surgery: This is not considered as the first line of treatment. It depends on the severity of the disease and the individual patient’s condition. In such cases, where surgery is deemed necessary, a lung volume reduction surgery or transplant is considered.

3. Emergency Management of Exacerbations: Prompt use of antibiotics to manage bacterial load, oral corticosteroids to reduce symptoms and inflammation, and using bronchodilators as inhalers should be done.

4. Regular Follow-up: Periodic lung function testing and imaging such as X-ray and CT scans should be performed along with clinical assessment of symptoms to monitor the disease progress and extent. Patient symptoms and exacerbations should be discussed with the patient.

Conclusion

COPD- bronchiectasis overlap syndrome is a complex mixture of both diseases. This overlap burdens the respiratory system and demands a multidisciplinary, comprehensive treatment approach. Consultations with pulmonologists, physiotherapists, and other healthcare providers are deemed necessary. Combining pharmacological approaches with non-pharmacological methods forms the base for a good treatment approach. As research is ongoing and newer modes of therapy are evolving, an individualized treatment approach seems promising.