What is the management approach for a patient with a persistent nocturnal cough?

Management of Persistent Nocturnal Cough

The management of persistent nocturnal cough should focus on identifying and treating the three most common causes: upper airway cough syndrome (UACS), asthma, and gastroesophageal reflux disease (GERD), using a systematic approach with empiric treatment trials based on the most probable aggravants. 1, 2

Initial Evaluation

• Mandatory assessments:

  • Chest radiograph (to rule out concerning conditions)
  • Spirometry (when age-appropriate)
  • Detailed history focusing on:
    • Timing of cough (nocturnal pattern)
    • Associated symptoms
    • Medication review (especially ACE inhibitors)
    • Smoking status
    • Occupational exposures

• Key diagnostic clues for nocturnal cough:

  • Asthma, infection, or heart failure can cause coughing that wakes patients 1
  • Cough that abates overnight may suggest reflux (due to closure of lower esophageal sphincter) 1
  • Sleep is known to suppress the cough reflex, with spontaneous cough almost abolished during deep sleep stages 1

Treatment Algorithm

Step 1: Address Modifiable Factors

• Discontinue ACE inhibitors regardless of temporal relationship to cough onset (resolution typically occurs within days to 2 weeks, median 26 days) 1
• Smoking cessation for smokers (majority experience cough resolution within 4 weeks) 1

Step 2: Empiric Treatment Based on Suspected Cause

1. For suspected Upper Airway Cough Syndrome:

   • First-generation antihistamine/decongestant combination for 2-4 weeks 2
   • In presence of prominent upper airway symptoms, trial of topical corticosteroid 1

2. For suspected Asthma:

   • Trial of inhaled corticosteroids and bronchodilators for 4 weeks 2
   • Consider short course of oral corticosteroids for severe symptoms 2
   • Cough is unlikely to be due to eosinophilic airway inflammation if no response to a two-week oral steroid trial 1

3. For suspected GERD:

   • Intensive acid suppression with proton pump inhibitors and alginates for minimum 3 months 1, 2
   • Important note: Reflux-associated cough may occur without gastrointestinal symptoms 1

Step 3: Symptomatic Relief for Nocturnal Cough

• First-generation antihistamines are effective for nocturnal cough 2
• Dextromethorphan for non-productive cough 2
• Inhaled ipratropium bromide may be considered as first-line therapy for post-infectious cough 2

Management of Refractory Nocturnal Cough

If cough persists despite targeted therapies for common causes:

1. Neuromodulators:

   • Gabapentin or pregabalin 2, 3
   • Low-dose morphine (preferred in refractory cases) 3

2. Non-pharmacologic approaches:

   • Speech pathology therapy for cough suppression techniques 2
   • Behavioral cough control therapy 3

3. Consider specialist referral:

   • Pulmonologist or otolaryngologist for persistent unexplained cough 4
   • Further investigations (bronchoscopy, HRCT) if cough persists after standard evaluation 2

Special Considerations

• Barking/honking quality of cough lacks specificity and should not be used to diagnose or exclude specific causes 1
• Tic cough should be considered if chronic cough remains medically unexplained and patient shows core clinical features (suppressibility, distractibility, suggestibility, variability) 1
• Somatic cough disorder requires meeting DSM-5 criteria and may benefit from non-pharmacologic approaches like hypnosis or suggestion therapy 1

Monitoring and Follow-up

• Assess cough severity before and after treatment using validated tools (visual analog scale) 2
• Schedule follow-up in 4-6 weeks to ensure symptom resolution 2
• Re-evaluate if cough persists beyond expected timeframe for treatment response

Common Pitfalls to Avoid

• Failing to consider GERD as a cause for cough (even without GI symptoms) 1
• Continuing ACE inhibitors in patients with persistent cough 1
• Inadequate duration of treatment (especially for GERD, which requires minimum 3 months) 1
• Overlooking non-asthmatic eosinophilic bronchitis as a potential cause 2, 4
• Using cough characteristics alone for diagnosis without appropriate investigations 1