Treatable traits in chronic cough
| Trait | Trait identification marker | Treatment | Expected benefits of treatment |
| Smoking | Patient history (cigarette smoking, chronic productive cough, worse in mornings). Urinary cotinine. Exhaled CO. | Smoking cessation. Nicotine replacement therapy (NRT). | Resolving chronic bronchitis→ improvement in cough. May get worse initially as nicotine suppresses cough reflex. Use NRT. |
| Irritant exposure: cigarette smoking/vaping, occupational exposures chemical/particulates | History occupational history Pets and hobbies | Reduce exposure | May improve cough |
| ACEI treatment | History (dry cough, throat symptoms). Medication records. | Stop ACEI in all patients with chronic cough. Can use A2RB if needed instead. | Improvement in cough, may take 4 weeks or more. |
| Airway eosinophilia | History (cough, possibly asthma type symptoms wheeze/breathless/nocturnal symptoms) FeNO>25ppb BEC (≥0.3×109/L) History | ICS Systemic corticosteroids | Improve cough and QoL Reduced exacerbations |
| Productive cough | History (significant sputum production, may be purulent). ? Underlying cause. Sputum C&S HRCT? bronchiectasis Bronchoscopy | Airway clearance/physiotherapy Mucolytics Antimicrobials Macrolides | Limited evidence. May improve cough |
| Chronic rhinosinusitis | History of two or more symptoms for ≥12 weeks, one of which should be either nasal blockage or nasal discharge (anterior or posterior), with or without facial pain/pressure or reduction or loss of smell | Nasal steroids Saline douching Consider ENT referral if symptoms do not improve with medical management and lifestyle changes. | Improvement in rhinosinusitis. Possible improvement in cough. Limited evidence. |
| Inducible laryngeal obstruction | History (wheeze, breathless, cough, inspiratory difficulties, dysphonia, symptoms variable) Laryngoscopy | Speech therapy intervention | May improve cough, limited evidence. |
| Obstructive sleep apnoea | History (snoring, daytime sleepiness, obesity) Sleep study. Epworth Sleep Score. High BMI | CPAP therapy Lifestyle advice Weight loss Mandibular advancement device | May improve cough, limited evidence for CPAP. No evidence for other measures. |
| Gastro-oesophageal reflux disease | History presence of heartburn best indicator of possible response to treatment. Reflux symptoms Oesophageal manometry and pH/MII Endoscopy Barium swallow High BMI | PPIs Lifestyle measures Also consider; H2 antagonists, weight loss? Fundoplication? | Limited evidence. May improve cough for a subgroup of patients. Most don’t improve. |
| Obesity | BMI Body habitus | Weight loss | May improve cough, no evidence. |
| Cough hypersensitivity | History (dry cough, triggered by trivial exposures for example, cold air/perfumes/talking, frequent laryngeal symptoms) Cough completely/partially refractory to addressing treatable traits or no treatable traits obvious. | Cough control therapy SLT Low dose SR morphine Gabapentin/pregabalin Clinical trials of new therapies | Improvements in cough frequency and QoL. |
| Anxiety/low mood | History Screening tool, for example, HAD score | Reassurance and explanation Psychological intervention Antidepressants | May improve cough, no evidence. |
A2RB, angiotensin 2 receptor blocker; BEC, blood eosinophil count; BMI, body mass index; CPAP, continuous positive airway pressure; ENT, ear, nose and throat; HAD, hospital anxiety and depression; ICS, inhaled corticosteroid; PPI, proton pump inhibitor; QOL, quality of life; SLT, speech and language therapy.