Practical approaches to chronic cough: Implementing the latest BTS recommendations

How should clinicians define and diagnose chronic cough, and what baseline assessments are recommended?

The BTS guidelines, in line with other guidance, define chronic cough as a cough lasting longer than 8 weeks. A cough that persists despite optimization of any identifiable, treatable traits, or where no cause can be found, is termed refractory chronic cough (RCC).

When a patient presents with chronic cough, several baseline assessments are required. The first step is to get the basics right: take a clear and thorough history. This should include identifying potential aggravating factors such as smoking or use of ACE inhibitors, as well as asking about sputum production, infective symptoms, and any red flags.

The aim is to identify treatable traits associated with the cough. It is also important to ask about cough-related syncope (passing out), particularly due to its implications for driving. If a patient reports syncope and is driving, they should be advised to stop driving and inform the DVLA while this is being investigated. Here, it is important to consult the DVLA website.

Following the history, a focused clinical examination is essential. Assess the upper airways and nose, and examine the chest for signs such as crackles (which might suggest pulmonary fibrosis or bronchiectasis) or wheeze (which might suggest obstructive airway disease). A cardiovascular examination is also important, as cardiac conditions can contribute to cough.

Baseline investigations, which can usually be performed in primary care, include assessment for type 2 (T2) inflammation by measuring peripheral eosinophils (via full blood count) and, where available, fractional exhaled nitric oxide (FeNO). A chest X-ray should be arranged to identify structural lung disease. Spirometry should be performed to assess for airflow obstruction or restriction, with bronchodilator reversibility testing if obstruction is present. If the patient is producing sputum, a sputum culture should also be sent.

How can clinicians use a treatable traits approach to structure assessment and initial management of chronic cough?

Assessment should aim to clarify the diagnosis, identify any underlying cough hypersensitivity, reassure the patient where no serious disease is present, improve understanding of the condition, and guide targeted treatment. The treatable traits approach supports all of these aims.

A treatable trait is a therapeutic target that can be identified with a biomarker and is amenable to treatment. This approach enables clinicians to target specific traits identified during assessment and, importantly, to exclude those that are not present. It reflects a precision medicine model, focusing on treating the individual’s specific drivers of disease rather than applying generic therapies.

As multiple traits may contribute to chronic cough, it is important to systematically consider each one during assessment, as outlined in the BTS guidance.

When should a patient with chronic cough be referred from primary to secondary care and when is urgent referral warranted?

Firstly, it’s important to recognize if red flags are present. If there is a concern about serious disease, such as cancer, and if red flags are present, an urgent or 2-week referral to the appropriate specialty should be made. Symptoms include if the patient is age ≥40 with a history of smoking or asbestos exposure; chest pain; systemic symptoms like weight loss or recurrent persistent infection; or persistent hoarseness of the voice; dysphagia; or haemoptysis.²

Referral from primary care is also appropriate when the diagnosis is unclear or when further investigation of suspected underlying disease is required. For example, a productive cough may raise suspicion of bronchiectasis, while inspiratory crackles may suggest interstitial lung disease (ILD); both should prompt specialist referral.²

At what point should non-pharmacological cough control therapies be integrated into the care pathway?

Non-pharmacological cough control therapy should be considered once a diagnosis of refractory chronic cough has been made and all treatable traits have been optimized, yet symptoms persist.

Unfortunately, these therapies are not widely available at present. They are typically delivered by speech and language therapists, and in some centres by physiotherapists. Although access remains limited, there is increasing emphasis on expanding availability, as these interventions are effective in managing refractory chronic cough.

Which common comorbidities should be routinely assessed and treated in chronic cough, and what should clinicians do when managing them does not improve symptoms?

The range of comorbidities and treatable traits associated with chronic cough is broader than previously recognized. While asthma, nasal disease and reflux were once considered the only treatable traits, other factors are now recognized to contribute. These include aggravants, such as ACE inhibitors and smoking, as well as associations with obesity and obstructive sleep apnoea.

Underlying lung or airway diseases, inducible laryngeal obstruction, gastro-oesophageal reflux, chronic rhinosinusitis, and recurrent infections should all be considered. Psychological comorbidities, including anxiety and low mood, are also common and should be addressed appropriately.

Cough hypersensitivity is another key trait. Patients often describe a dry, tickling cough with an urge to cough centred in the throat. Common triggers include mechanical stimuli (e.g. talking, laughing), chemical irritants (e.g. smoke, perfume), and temperature changes. Recognition of this pattern should raise suspicion of cough hypersensitivity.

If symptoms do not improve despite treatment of identified comorbidities and traits, clinicians should consider a diagnosis of refractory chronic cough and shift focus towards managing cough hypersensitivity, including the use of antitussive therapies.

When should pharmacological therapies for cough hypersensitivity or refractory chronic cough be considered?

Pharmacological treatment should be considered in patients with refractory chronic cough whose symptoms remain troublesome despite optimisation of underlying conditions and treatable traits.

Antitussive therapy may be used alone or in combination with non-pharmacological approaches, where available. However, it is essential to ensure that comorbid conditions—such as asthma or other airway diseases—are adequately controlled before initiating these treatments.