What are the guidelines for managing chronic cough?

Guidelines for Managing Chronic Cough

For adults with chronic cough, a systematic approach using a validated guideline is recommended, with treatment directed at the most common causes: upper airway cough syndrome (UACS), asthma, non-asthmatic eosinophilic bronchitis (NAEB), and gastroesophageal reflux disease (GERD). 1

Definition and Initial Evaluation

• Adults: Chronic cough is defined as cough lasting >8 weeks 2
• Children: Chronic cough is defined as cough lasting >4 weeks 2

Initial Assessment for All Patients:

• Chest radiograph and spirometry (when age appropriate) 1
• Evaluate for red flags:
  • Adults: fever, weight loss, hemoptysis, recurrent pneumonia 3
  • Children: digital clubbing, chest pain, failure to thrive, feeding difficulties, abnormal lung examination, hemoptysis, recurrent pneumonia, family history of chronic lung disease, immunodeficiency 4

Management Algorithm for Adults

Step 1: Rule Out or Address Common Contributors

• Smoking: Cessation should be encouraged as it significantly improves cough symptoms 1
• ACE inhibitors: Discontinue and replace with alternative medication 1
• Environmental triggers: Identify and avoid irritants 1

Step 2: Sequential Empiric Treatment Approach

Treatment should be given in sequential and additive steps as multiple causes may coexist 1:

1. First: UACS (Post-nasal drip)

   • Begin with oral first-generation antihistamine/decongestant 1
   • In presence of prominent upper airway symptoms, trial of topical corticosteroid 1

2. Second: Asthma/Airway Hyperresponsiveness

   • If spirometry doesn't show reversible airflow obstruction, perform bronchial provocation challenge (BPC) if available 1
   • If BPC unavailable, trial of inhaled corticosteroids, inhaled β-agonists, or oral leukotriene inhibitors 1
   • Note: A negative BPC excludes asthma but not steroid-responsive cough 1

3. Third: NAEB

   • Consider induced sputum test for eosinophils if available 1
   • If unavailable, empiric trial of corticosteroids 1

4. Fourth: GERD

   • Intensive acid suppression with proton pump inhibitors and alginates for minimum 3 months 1
   • Note: Reflux-associated cough may occur without gastrointestinal symptoms 1

Step 3: Refractory Chronic Cough

For patients who fail to respond to the above treatments:

• Consider referral to specialist cough clinic 1
• Trial of neuromodulators (gabapentin, pregabalin) 2, 5
• Speech therapy 5

Management Algorithm for Children

Assessment and Classification

• Categorize cough as specific (with pointers to underlying disease) or non-specific 1
• Evaluate for tobacco smoke exposure and other pollutants 1
• Assess child's activity, parental expectations, and concerns 1

Management Based on Cough Type:

1. Specific Cough (with pointers)

   • Investigate based on clinical findings for:
     • Bronchiectasis
     • Retained foreign body
     • Aspiration lung disease
     • Atypical respiratory infections
     • Cardiac anomalies
     • Interstitial lung disease 1

2. Non-specific Cough (dry cough, no pointers)

   • Watch, wait, and review approach
   • Usually post-viral cough or acute bronchitis
   • Consider foreign body inhalation, asthma, upper airway disorders, medication side effects 1

3. Protracted Bacterial Bronchitis (PBB)

   • Appropriate antibiotics for 2 weeks
   • Extend treatment additional 2 weeks if cough persists
   • Further investigations if cough persists after 4 weeks of antibiotics 4

Important Considerations for Children

• Do not use: Over-the-counter cough and cold medicines, codeine-containing medications, or dextromethorphan due to lack of efficacy and potential harm 4
• Consider honey for symptom relief: 10ml mixed with milk or warm water before bedtime (up to three times daily) 4

Follow-up and Monitoring

• Re-evaluate until diagnosis is found with resolution of cough 1
• For children with persistent cough and hypoxia, follow-up within 1 week after hospital discharge 4
• Serial monitoring for patients with partial response to treatment 1

Common Pitfalls to Avoid

• Failing to consider GERD as a cause for cough (common reason for treatment failure) 1
• Inadequate duration of empiric treatments (minimum 3 months for GERD) 1
• Not recognizing that cough may be the only manifestation of asthma or NAEB 1
• Continuing ACE inhibitors in patients with chronic cough 1
• Using cough suppressants in children or when cough clearance is important 1, 4

By following these systematic, evidence-based guidelines, most cases of chronic cough can be effectively diagnosed and managed, improving patient quality of life and reducing morbidity.