Chronic Cough. Dr Peter George Consultant Respiratory Physician Royal Brompton and Harefield Hospitals

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1 Chronic Cough Dr Peter George Consultant Respiratory Physician Royal Brompton and Harefield Hospitals

2 Overview Common causes of chronic cough Important diagnoses not to miss How to investigate a cough in general practice How to effectively treat cough Less commonly considered diagnoses When to refer

3 Acute Cough Acute cough is one lasting less than 3 weeks Commonest new presentation in primary care Most commonly associated with a viral URTI In the absence of significant co-morbidity, usually benign and self-limiting Commonest symptom associated with acute exacerbations and hospitalisation with asthma and COPD BTS 2006

4 Chronic Cough Defined as lasting for more than 8 weeks Accounts for 10% of respiratory referrals to secondary care Significant impact on quality of life Most patients have dry / minimally productive cough Presence of significant sputum production indicates lung pathology Commoner in middle aged females Likely due to increased sensitivity of cough reflex BTS 2006

5 My approach to chronic cough 1. Make sure I m not missing a red flag diagnosis Cancer / Pulmonary Fibrosis / Inhaled foreign body 2. Make sure I m not missing a common diagnosis Asthma / COPD / Heart Failure / Bronchiectasis 3. Make sure I m not missing an easily treated condition GORD / Post-Nasal Drip / Ear-Cough reflex 4. Make sure there are no obvious culprit drugs ACE-i / Statin 5. Make sure I m not missing laryngeal hypersensitivity 6. Make sure I ve given trials of treatment Refer to specialist cough clinic!

6 Chronic Cough - History Smoking is one of the commonest causes of persistent cough Dose related Often report that cough changes in character after stopping smoking Diurnal variation Nocturnal cough commoner in asthma and heart failure Drugs ACE-I (can persist for some months after withdrawal) Statins GORD Cough on speaking on telephone / laughing / singing Post nasal drip Occupational / environmental exposures Work place sensitisers Dust or chemical exposure Triggers and dysphonia with upper airway symptoms Laryngeal hypersensitivity

7 Chronic Cough - Examination Key is to exclude a respiratory cause for the cough Asthma / COPD / Pulmonary fibrosis / Bronchiectasis Clubbing Wheeze or crackles on auscultation should prompt further Ix Cardiac failure can cause cough Elevated JVP / pedal oedema ENT examination helpful if skilled in this Polyps Inflamed turbinates Erythema of larynx and pharynx suggestive of chronic reflux

8 Blood tests Investigation of chronic cough in primary care Eosinophilia may suggest atopic disease or asthma Anaemia of chronic disease may suggest malignancy Hypercalcaemia -? sarcoidosis or lung cancer Chest radiograph mandatory FeNO helpful in diagnosing asthma or steroid responsive cough Spirometry crucial in identifying obstructive v restrictive disease FEV 1 FVC < 70% Obstructive COPD or asthma FEV 1 FVC > 70% Restrictive Pulmonary fibrosis

9 Management of chronic cough in primary care Who to refer urgently? Anyone with a red flag diagnosis Suspected foreign body inhalation Acute on chronic infection Complication of acute bacterial infection

10 Management of chronic cough Easy! When there is an obvious cause GORD 3 month trial of combination PPI / Ranitidine / Gaviscon Post nasal drip Fluticasone nasal spray / Saline douche Removal of potential causative medications Asthma Start with low dose inhaled steroid Bronchiectasis Physiotherapy and antibiotics Elevated FeNO (>45) Trial of inhaled corticosteroid

11 Management of chronic cough Not easy! When there isn t an obvious cause Idiopathic chronic cough and cough hypersensitivity syndrome Cough Hypersensitivity Syndrome Enhanced cough reflex of unknown aetiology Change in temperature / bleach / dust / strong perfume /pollution / cigarette smoke Commonest in middle aged women

12 Less common diagnoses Eosinophilic Bronchitis Not that uncommon responsible for 12% of cases of isolated chronic cough in tertiary referral clinics Characterised by airway eosinophilia with high levels of eosinophils in the sputum Significant overlap with asthma but often have normal spirometry and chest radiographs and do not improve with salbutamol Can be diagnosed on sputum cytology high eosinophil level Often diagnosed with therapeutic trial of steroids Prednisolone 30mg for 7 days should clear up cough within 3-4 days

13 Laryngeal Hypersensitivity Less common diagnoses Patients often report symptoms arising in the throat in response to non-specific stimuli Dust / air pollution / cigarette smoke / bleach / Boots perfume counter Cross over with other laryngeal dysfunction syndromes Dysphonia Change in quality of voice over course of the day Unexplained breathlessness and inappropriate adduction of vocal cords at times resulting in inspiratory wheeze / stridor Frequent throat clearing Treatment Specialist opinion Speech and Language therapy Voice retraining Physiotherapy Laryngeal hygiene

14 Ear-Cough Reflex Less common diagnoses Cough originates from stimulation of structures innervated by the vagus nerve Ear-Cough (Arnold s nerve) reflex is cough caused by stimulation of the external auditory canal (innervated by auricular branch of vagus) Dispingaitis et al. Chest. In Press 2018

15 Ear-Cough Reflex Less common diagnoses Study of 200 adults and 100 children with chronic cough Stimulation of the external auditory canal with a cotton bud Cough within 10 second of stimulation was positive Reflex present in 26% of adults with chronic cough (32% of women, 13% of men) v 2% of healthy adults Think about the potential benefits of removal of ear wax for patients with chronic cough! Dispingaitis et al. Chest. In Press 2018

16 Idiopathic chronic cough Cough should only be considered idiopathic following thorough assessment at a specialist cough clinic In up to 20% of referrals to a cough clinic, the cause remains unknown Idiopathic chronic cough and cough hypersensitivity Most commonly middle aged women Longstanding dry cough which starts at around the menopause Often appears to follow a viral respiratory tract infection Autoimmune disease (esp hypothyroidism is common)

17 Idiopathic chronic cough Pharmacological Approaches Treatment is challenging and is currently largely limited to non-specific antitussive therapy Low dose nocturnal amitryptiline Gabapentin Opiates such as codeine can temporarily help Beware use of cough suppression in conditions where the cough is helpful / protective Infection Bronchiectasis Dysphagia

18 Idiopathic chronic cough Non-Pharmacological Approaches Cough hypersensitivity Manuka honey has antibacterial and anti-inflammatory properties Cloves are a natural remedy used regularly in Indian subcontinent with analgesic and anti-tussive properties Or both! Some patients find benefit from sucking cloves dipped in Manuka honey If symptoms localise to throat or larynx Hydration Avoidance of caffeinated or carbonated drinks Speech and language therapy

19 New Therapies are coming Idiopathic chronic cough Existing approaches non-selective and largely unrewarding Arrival of P2X3 inhibitors MK-7264 moving into Phase III trials Reduction in cough frequency by 37% v placebo in patients with refractory chronic cough Effect maintained over 12 week treatment duration Main side effect was effect on taste in almost 75% of patients Consider referring your patients to recruiting centres! Royal Brompton Hospital has 3 Phase III Clinical trials for patients with chronic cough that start recruiting in Jan 2018

20 Summary Chronic cough is a common symptom Can be an important symptom of serious underlying respiratory pathology - don t miss the red flags Keep in mind the easily remediable diagnoses Trials of treatment reasonable Consider cough hypersensitivity syndrome drugs are coming! Refer patients to a specialist cough clinic as chronic cough is a debilitating and socially embarrassing symptom

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