Respiratory Lung Disease Overlap

Respiratory lung disease overlap, also known as overlap syndrome, occurs when someone experiences symptoms and characteristics of two or more distinct lung conditions at the same time.

These overlaps typically occur due to a decline in lung function and occasionally incomplete lung growth in children, however, the occurrence of specific conditions overlapping depends on causes related to each condition experienced.

Group 346

Common Respiratory Lung Disease Overlaps

Respiratory lung disease overlap can manifest in various forms, with some of the most common overlaps occurring between chronic obstructive pulmonary disease (COPD) and asthma, COPD and bronchiectasis, asthma and bronchiectasis, and interstitial lung disease (ILD) and emphysema.

COPD and Asthma

COPD and asthma are both chronic inflammatory lung diseases characterised by airflow limitation, although their underlying mechanism and triggers differ. While COPD is often associated with smoking and environmental pollutants, asthma is typically triggered by allergens and respiratory irritants. However, in some cases, patients may exhibit features of both conditions, leading to a diagnosis of asthma-COPD overlap (ACO).

COPD and Bronchiectasis

Bronchiectasis is a chronic respiratory condition characterised by abnormal, irreversible dilation of the airways (bronchi), leading to recurrent infections and airway inflammation. It often coexists with COPD, particularly in people with a history of chronic bronchitis or recurrent respiratory infections. The presence of bronchiectasis in COPD patients can exacerbate symptoms and increase the risk of acute exacerbations, necessitating tailored management approaches.

Asthma and Bronchiectasis

Similarly, asthma and bronchiectasis can overlap, particularly in people with severe, poorly controlled asthma. The chronic airway inflammation seen in asthma can contribute to the development of bronchiectasis over time. Managing this overlap requires a comprehensive assessment of airway inflammation, bronchial hyperresponsiveness, and infectious triggers to optimise treatment outcomes.

Interstitial Lung Disease (ILD) and Emphysema

ILD encompasses a diverse group of lung disorders affecting the functional tissue of the lungs and are characterised by inflammation and fibrosis of the lung tissue. Emphysema, on the other hand, is a subtype of COPD characterised by destruction of the lung tissue and enlargement of airspaces. In some cases, patients may present with features of both ILD and emphysema, posing diagnostic therapeutic challenges. Treatment strategies aim to mitigate inflammation, preserve lung function, and improve quality of life through a multidisciplinary approach involving pulmonologists, radiologists, and rheumatologists.


Symptoms associated with respiratory lung disease overlap will depend on the types of lung conditions the patient has. However, the most common symptoms of lung diseases and lung disease overlaps include:

  • Wheezing
  • Persistent coughing
  • Breathlessness
  • Fatigue
  • Excess mucus
  • Difficulty breathing
  • Chest tightness
  • Recurrent respiratory infections

Implications for Diagnosis and Management

Respiratory lung disease overlap can complicate diagnosis, treatment, and management as these strategies can differ significantly depending on the types of conditions overlapping. Diagnosing respiratory lung disease overlap requires a thorough evaluation of clinical symptoms, pulmonary function tests, imaging studies, and in some cases, biomarker assessments. Healthcare providers must carefully assess the underlying mechanisms and characteristics of each condition to develop personalised treatment plans.

Treatment Options

Treatment options for respiratory lung disease overlaps often involve a combination of interventions aimed at addressing both obstructive and restrictive components of the disease.

  • Bronchodilators: These are medications that help relax the muscles around the airways, improving airflow and alleviating symptoms such as wheezing and breathlessness.
  • Inhaled Corticosteroids: Anti-inflammatory medications commonly used in asthma management to reduce airway inflammation and prevent exacerbations.
  • Mucolytics: Mucolytic agents such as hypertonic saline or dornase alfa can help liquefy thick mucus in bronchiectasis, facilitating clearance and reducing the risk of respiratory infections.
  • Antibiotics: These may be prescribed to treat acute exacerbations of bronchiectasis associated with bacterial infection.
  • Pulmonary Rehabilitation: Rehabilitation programs offer structured exercise training, education, and support to improve lung function and physical fitness.
  • Supplemental Oxygen Therapy: This therapy may be prescribed to improve oxygenation and alleviate symptoms of hypoxemia in people with ILD, emphysema, or overlap syndromes.

Respiratory lung disease overlap presents complex challenges for both patients and healthcare providers. Navigating these overlapping conditions requires a holistic approach that addresses the underlying mechanisms, characteristics, and individual patient needs.

Support your lung health today with specialised care from North Brisbane Sleep and Thoracic.

Contact us to book an appointment

Visit us at either our Clayfield or North Lakes location and experience compassionate care in a comfortable environment, tailored to meet your unique needs.