Cough Upon Falling Asleep That Stops Once Asleep
This patient most likely has gastroesophageal reflux disease (GERD) causing cough during the transition to sleep, which then resolves once the lower esophageal sphincter closes during established sleep. 1
Understanding the Timing Pattern
The specific pattern of coughing only when falling asleep but stopping once asleep is highly characteristic of GERD-related cough. 1 Here's why:
- Sleep suppresses the cough reflex, particularly during deep sleep stages 3 and 4, which explains why the cough stops once the patient is fully asleep. 1, 2
- A cough that abates overnight is specifically associated with reflux due to closure of the lower esophageal sphincter during established sleep. 1
- The transition period when falling asleep represents a vulnerable window when reflux can occur before protective sleep mechanisms fully engage. 1
- Ambulatory recordings have demonstrated a marked reduction in cough overnight in patients with various causes of chronic cough. 1
Recommended Treatment Approach
First-Line Management
Initiate comprehensive GERD therapy immediately, as this is the most likely diagnosis based on the timing pattern:
- Start a proton pump inhibitor (PPI) at standard dose once daily for 4-8 weeks. 3
- Implement antireflux lifestyle modifications: avoid eating within 2-3 hours of bedtime, elevate the head of the bed, avoid trigger foods, pursue weight management if overweight, and smoking cessation if applicable. 3
Treatment Escalation
If inadequate response after 4-8 weeks:
- Increase to twice-daily PPI dosing. 3
- Consider adding a prokinetic agent such as metoclopramide if there is little or no response to PPI alone. 3
- Consider 24-hour esophageal pH monitoring to confirm the diagnosis if symptoms persist despite optimized therapy. 3
Alternative Diagnoses to Consider
Obstructive Sleep Apnea (OSA)
OSA should be strongly considered if GERD treatment fails, as it has recently been recognized as a cause of chronic cough, particularly nocturnal cough. 4, 2
Key features suggesting OSA:
- Nocturnal cough with snoring and gastroesophageal reflux. 4
- Daytime somnolence is often absent in OSA patients presenting with cough. 4
- Female patients are more likely to present with cough as the primary OSA symptom. 2
- Continuous positive airway pressure (CPAP) therapy is effective in alleviating cough in OSA patients. 4, 5
Upper Airway Cough Syndrome (UACS)
While less likely given the specific timing:
- UACS typically causes morning cough due to mucus accumulation during sleep. 6
- The cough is often associated with frequent throat clearing or sensation of postnasal drip. 1, 6
- Trial of a decongestant and first-generation antihistamine is warranted if UACS is suspected. 7
Asthma
Less consistent with this timing pattern:
- Asthma typically causes coughing that wakes patients during the night or early morning, not cough that stops once asleep. 1, 6
- If asthma is suspected, confirm diagnosis with clinical response to empiric therapy with inhaled bronchodilators or corticosteroids. 7
Critical Clinical Pearls
- Up to 75% of patients with GERD-related cough lack typical gastrointestinal symptoms (silent GERD), so absence of heartburn does not rule out this diagnosis. 6, 3
- Response to GERD therapy may take several months in some patients, so adequate treatment duration is essential. 3
- Women, particularly middle-aged women, have higher prevalence of chronic cough and more sensitive cough reflex. 1, 6
- ACE inhibitors can cause chronic cough and should be discontinued if the patient is taking one. 1, 6, 7
Diagnostic Algorithm
- Review medications - discontinue ACE inhibitors if present. 7
- Initiate empiric GERD therapy with PPI and lifestyle modifications for 4-8 weeks. 3
- If no response, increase to twice-daily PPI or add prokinetic agent. 3
- If still no response, consider polysomnography to evaluate for OSA. 4, 2
- If OSA confirmed, initiate CPAP therapy which effectively alleviates cough. 4, 5