What is the differential diagnosis for a 60-year-old patient presenting with a new onset nighttime cough?

Differential Diagnosis for Nighttime Cough in a 60-Year-Old Patient

The most common causes of new-onset nighttime cough in a 60-year-old are asthma (including cough-variant asthma), upper airway cough syndrome (postnasal drip), gastroesophageal reflux disease (GERD), and heart failure—each requiring systematic evaluation rather than assuming nighttime timing is diagnostically specific. 1, 2

Critical Initial Considerations

Life-Threatening Conditions to Exclude First

• Cardiac failure must be ruled out immediately in patients over 65 years, especially if there is orthopnea, history of myocardial infarction, or displaced apex beat, as heart failure commonly presents with cough mimicking respiratory conditions 2
• Pneumonia should be suspected if the cough is accompanied by fever lasting >4 days, new focal chest signs, dyspnea, or tachypnea—obtain chest radiograph for confirmation 2
• Pulmonary embolism warrants consideration if there is history of deep vein thrombosis, recent immobilization (past 4 weeks), or active malignancy 2

Medication-Induced Cough

• ACE inhibitor use is a common and immediately reversible cause—inquire about this medication first and switch to another drug class if identified 3, 2
• Beta-adrenergic blocking medications may exacerbate underlying asthma and should be evaluated 3

Most Common Causes in This Age Group

Asthma and Cough-Variant Asthma

• Asthma is strongly associated with nocturnal cough, though the presence or absence of nighttime cough alone should not be used to diagnose or exclude any specific condition 4
• Look for wheezing, prolonged expiration, symptoms of allergy, or smoking history (≥2 of these features increases likelihood) 2
• Cough-variant asthma presents as isolated cough without objective evidence of variable airflow obstruction but with bronchial hyperresponsiveness present 4
• Spirometry with bronchodilator testing should be performed; if normal, tests of airway responsiveness are more sensitive and specific than bronchodilator reversibility studies 4, 3
• Eosinophilic bronchitis (non-asthmatic) presents with eosinophilic airway inflammation but without airway hyperresponsiveness—this is a common cause accounting for approximately 30% of cough referrals 4, 2

Upper Airway Cough Syndrome (Postnasal Drip)

• Upper airway cough syndrome represents 61-67% of chronic cough cases in referral settings and is the most common cause 2
• Evaluate for signs of postnasal drainage, throat clearing, nasal congestion, or sinus disease 5

Gastroesophageal Reflux Disease (GERD)

• GERD is one of the four most common causes requiring systematic empiric treatment 2
• Nocturnal cough is commonly associated with GERD due to supine positioning facilitating reflux 1
• Consider GERD even without classic heartburn symptoms, as silent reflux can present with isolated cough 5

Chronic Bronchitis and Smoking-Related Disease

• In this age group (60 years), chronic bronchitis and early chronic obstructive pulmonary disease should be considered, especially with any smoking history 5, 6
• Obtain detailed smoking history and consider pulmonary function testing 3

Less Common but Important Diagnoses

Bronchiectasis

• Bronchiectasis accounts for 8-12% of chronic cough cases in referral settings 2
• Chest CT is the reference standard for diagnosis if suspected 2

Interstitial Lung Disease

• Interstitial lung disease is found in 8% of chronic cough referral cases 2
• May require chest CT for diagnosis if chest radiograph is unrevealing 2

Sarcoidosis

• Sarcoidosis affects 40-80% of symptomatic patients with cough and is related to granulomatous inflammation in airways, with airway obstruction identified in more than half of patients regardless of smoking status 1
• Consider in patients with systemic symptoms or hilar lymphadenopathy 1

Broncholithiasis and Foreign Body

• Broncholithiasis from calcified peribronchial lymph nodes can cause abrupt-onset harsh cough, sometimes with hemoptysis or lithoptysis 4
• Foreign body aspiration (unwitnessed) can lead to persistent harsh cough, though bronchoscopy yield is low (0.3%) without specific history 4

Diagnostic Approach Algorithm

Initial Evaluation

• Obtain chest radiograph to rule out pneumonia, malignancy, structural abnormalities, heart failure, or infiltrates 3, 2
• Measure vital signs: respiratory rate >24 breaths/min, heart rate >100 beats/min, or temperature >38°C increases likelihood of pneumonia 4
• Perform spirometry with bronchodilator testing to assess for asthma or obstructive lung disease 3

When Initial Tests Are Normal

• Consider empiric treatment trials for the most likely diagnoses (upper airway cough syndrome, asthma, GERD) in sequential and additive steps rather than stopping after identifying one etiology 2
• If corticosteroid-responsive cough is suspected, expert opinion suggests a trial of prednisolone 30 mg/day for 2 weeks; if no response, consider alternative diagnosis 4
• Multiple causes frequently coexist—therapy should be given sequentially and additively 2

Critical Pitfalls to Avoid

• Do not use nighttime cough presence or absence as a diagnostic criterion for psychogenic cough, asthma, or any specific condition—it is not sufficiently specific 4, 1
• Do not overlook cardiac causes in elderly patients presenting with respiratory symptoms, as heart failure mimics respiratory infections 2
• Do not assume a single etiology—up to 90% of chronic cough cases have common nonmalignant causes that often overlap 7, 6
• In elderly patients (>65 years), maintain high suspicion for atypical presentations of serious conditions like pneumonia, even with normal vital signs 2