What are the most common respiratory issues and clinical signs in smokers with chronic obstructive pulmonary disease (COPD)?

From the Guidelines

Smokers commonly experience respiratory issues such as chronic obstructive pulmonary disease (COPD), chronic bronchitis, emphysema, and increased risk of respiratory infections and lung cancer, with the most prominent clinical signs including a persistent cough, increased sputum production, wheezing, shortness of breath (dyspnea), decreased exercise tolerance, and chest tightness, as reported in the 2018 GOLD report 1. The most frequent symptoms of COPD include dyspnea, cough, and/or sputum production, which are commonly underreported by patients, according to the 2017 GOLD executive summary 1. Some key points to consider in the diagnosis and management of COPD include:

• A postbronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio of less than 0.70, which confirms the presence of persistent airflow limitation 1
• Appropriate symptoms, including dyspnea, chronic cough, sputum production, or wheezing 1
• Significant exposures to noxious stimuli, such as a history of smoking cigarettes, or other environmental exposures 1
• Comorbidities, such as ischemic heart disease, lung cancer, osteoporosis, depression, and others, which can contribute to the clinical severity of patients with COPD and affect important patient-centered outcomes 1 Physical examination may reveal prolonged expiration, diminished breath sounds, barrel chest appearance in advanced cases, and occasionally cyanosis, as well as reduced oxygen saturation, increased respiratory rate, and use of accessory muscles for breathing during exacerbations. These respiratory issues develop because cigarette smoke contains thousands of harmful chemicals that cause inflammation, oxidative stress, and structural damage to the airways and lung tissue, as discussed in the 2017 GOLD executive summary 1. The irritants in smoke damage the cilia that help clear mucus, leading to mucus accumulation and creating an environment conducive to infections, and over time, this chronic inflammation and repeated damage leads to permanent structural changes in the lungs, including airway remodeling and destruction of alveolar walls, resulting in the progressive respiratory symptoms observed in long-term smokers. It is essential to note that high-quality spirometry is crucial for the diagnosis of COPD, but it is often underused by clinicians in clinical practice, as highlighted in the 2018 GOLD report 1. In addition, the 2015 American Thoracic Society/European Respiratory Society statement emphasizes the importance of considering comorbidities and systemic effects in the management of COPD, as they can significantly impact patient-centered outcomes 1.

From the Research

Common Respiratory Issues in Smokers

• Chronic Obstructive Pulmonary Disease (COPD) is a common lung condition caused by chronic lung inflammation, often resulting from smoking 2
• Smokers without overt airflow obstruction on spirometry can still experience respiratory symptoms, poor quality of life, and low functional capacity 3
• Smoking is also linked to an increased risk of lung cancer, with people suffering from COPD being more susceptible to poor outcomes after diagnosis and treatment 4

Clinical Signs of Respiratory Issues in Smokers

• Respiratory symptoms such as dyspnea, coughing, and wheezing are common in smokers with COPD 2
• Smokers with normal spirometry can still exhibit evidence of structural lung disease on imaging and suffer from respiratory exacerbations 3
• Chronic bronchitis is a marker identifying high-risk individuals for COPD and mortality 5
• Severe COPD is associated with the most rapid decline in lung function, which is linked to COPD-related hospitalization and mortality 5

Underlying Pathophysiology

• Smoking can lead to an underlying genetic predisposition, epithelial and endothelial cell plasticity, and dysfunctional inflammatory mechanisms, increasing the risk of lung cancer 4
• COPD could be the driving factor for lung cancer, providing a conducive environment that propagates its evolution 4
• The relationship between tobacco smoking and various respiratory conditions, including obstructive lung diseases, lung cancer, and bacterial and viral respiratory infections, is complex and multifaceted 6