Jemma Haines and Dr Paul Marsden advise on another aspect of long Covid
Cough is one of the most common symptoms presenting to primary care.1
In ‘acute cough’ (less than three weeks), the majority of cases are due to viral upper respiratory tract infections. In the absence of significant comorbidity, they usually resolve without investigation and intervention. Coughing that lasts more than eight weeks is defined as chronic. It affects about 10% of the adult population2 and causes significant morbidity.
Globally, cough is the most commonly reported symptom in acute Covid-19 infection. Between 50-80% of those infected report a dry persistent cough.3
But despite the high prevalence of cough in the acute infective period, early data indicate that post-viral cough is neither a frequent nor a debilitating residual effect.4 In a recent prospective UK cohort study of hospitalised patients with Covid-19, the most common ongoing symptoms were breathlessness (39%), fatigue (39%) and insomnia (24%), with only 11.6% reporting residual cough.5 Similarly, only 7% of patients (n=119) who had Covid-19 and associated severe pneumonia reported a troublesome chronic cough two months post infection.6 The prevalence of post-infective cough in non-hospitalised Covid-19 cases is unreported.
Types of cough in long Covid
At the end of 2020, it was estimated that 186,000 individuals in private households in England were experiencing long Covid symptoms, following confirmed or suspected infection.7 Therefore, even though there is a low incidence of post-Covid cough, there will be a significant minority seeking healthcare support for ongoing cough.
However, there is little to support the idea that ‘Covid cough’ is a distinct entity in itself, but instead is part of long Covid with the other post-infective symptoms including chronic fatigue and dyspnoea and may relate to a central sensitisation process.8 Future research is needed on cough with long Covid.
There is no evidence to support specific treatment or investigation recommendations other than ensuring the acute illness and radiological changes have resolved. If you suspect bacterial infection is complicating Covid (there is fever, purulent sputum and blood neutrophilia), this should be treated.
A proportion of patients will develop complications such as interstitial lung disease or fibrosis following Covid.
If there are ongoing radiological changes after six weeks, consider referral to a chest clinic for CT imaging and further investigation.
If all residual radiological changes have resolved, persistent cough following Covid should be investigated as per recognised guidelines for the management of chronic cough.
Persistent cough following Covid-19
We do not differentiate between those with persistent cough following Covid and those who present with chronic cough. The first-line management for people with residual cough after Covid-19 infection are the same as British Thoracic Society guidelines on the management of cough in adults:1
• Take a chest X-ray. If abnormal in keeping with Covid, repeat after four to six weeks to ensure resolution.
• Perform spirometry.
• Stop ACE inhibitors as they increase the sensitivity of the cough reflex and can affect treatment response.
• Manage any potential aggravants, such as asthma, eosinophilic bronchitis, gastro-oesophageal reflux or upper airway pathology.
• Refer if you have concerns or the cough remains uncontrolled.
If patients present with a new cough with purulent sputum following Covid, bacterial infection should be considered and treated according to standard chronic cough guidelines.
Advice for patients with ongoing dry cough
- Gently breathe in and out through your nose, until the urge to cough goes away
- Practise a ‘normal’ breathing pattern – gentle, quiet, diaphragmatic (tummy breathing – feeling the tummy rise and fall as you breathe in and out), through the nose at rest to start with. Aim to practise this little and often so that it becomes habit. Progress this by practising during gentle activity as you are able
- Close your mouth and swallow
- Sip drinks regularly (hot or cold)
- Suck boiled sweets or lozenges
Source: NHS, Your Covid Recovery site
Consider rapid referral if patients present with any of the following:
• Unintentional weight or appetite loss.
• Associated breathlessness or palpitations.
• Persistent dysphonia or noisy breathing.
• Significant odynophagia.
Also refer urgently if they are smokers or use alcohol to excess.
What advice can I give patients?
It is important to differentiate whether the ongoing cough is productive or non-productive. If it is productive with mucous secretions, direct cough suppression strategies should be avoided to reduce the risk of mucus retention and recurrent chest infection.
Discuss techniques to reduce coughing or aid chest clearance.
The yourCovidrecovery.nhs.uk site has a section on this. If applicable, encourage smoking cessation as stopping or cutting down will ease a persistent cough.
When and where should I refer?
Refer if the patient is not benefiting from management strategies, and their Covid infection was more than 12 weeks ago. Referral information should quantify cough severity and previous treatment effects, together with chest radiography and spirometry findings.
For those with ongoing cough as part of a multi-symptom presentation post Covid, refer to a long Covid clinic.
If cough is an isolated post-infective symptom, refer to a secondary care respiratory or specialist cough clinic.
Jemma Haines is airways service lead and consultant speech and language therapist at Manchester University NHS Foundation Trust
Dr Paul Marsden is consultant chest physician and clinical lead of Manchester Cough Service
1 Morice A, McGarvey L, Pavord I. British Thoracic Society Cough Guideline Group Recommendations for the management of cough in adults. Thorax 2006;61 Suppl 1:i1-24. doi: 10.1136/thx.2006.065144
2 Song W, Chang Y, Faruqi S et al. The global epidemiology of chronic cough in adults: a systematic review and meta-analysis. Eur Respir J 2015;45:1479-81. doi: 10.1183/09031936.00218714
3 Israfil S, Sarker M, Rashid P. Clinical Characteristics and Diagnostic Challenges of Covid-19: An Update From the Global Perspective. Front Public Health 2021;8:567395. doi: 10.3389/fpubh.2020.567395
4 Dicpinigaitis P, Canning B. Is There (Will There Be) a Post-Covid-19 Chronic Cough? Lung 2020;198:863-5. doi: 10.1007/s00408-020-00406-6
5 Arnold D, Hamilton F, Milne A et al. Patient outcomes after hospitalisation with Covid-19 and implications for follow-up: results from a prospective UK cohort. Thorax 2020 Dec 3:thoraxjnl-2020-216086. doi: 10.1136/thoraxjnl-2020-216086
6 D’Cruz R, Waller M, Perrin F et al. Chest radiography is a poor predictor of respiratory symptoms and functional impairment in survivors of severe Covid-19 pneumonia. ERJ Open Res 2021;7:00655-2020. doi: 10.1183/23120541.00655-2020
7 Ayoubkhani, D. Prevalence of long Covid symptoms and Covid-19 complications. Office for National Statistics. https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/healthandlifeexpectancies/datasets/prevalenceoflongcovidsymptomsandcovid19complications
8 Song W, Hui C, Hull J et al. Confronting Covid-19 associated cough and the post-Covid syndrome: role of viral neurotropism, neuroinflammation, and neuroimmunce responses. The Lancet respiratory medicine, Epub ahead of print https://doi.org/10.1016/S2213-2600(21)00125-9