Chronic Cough Etiologies and Management

Primary Etiologies

The American Thoracic Society suggests that upper airway cough syndrome (UACS) from rhinosinus conditions, asthma, gastroesophageal reflux disease (GERD), and nonasthmatic eosinophilic bronchitis are the most common causes of chronic cough, either alone or in combination, accounting for more than 90% of cases 1, 2
Upper Airway Cough Syndrome (UACS) is one of the top three causes of chronic cough, previously called postnasal drip syndrome, encompassing various rhinosinus conditions 1, 3
Asthma, including cough-variant asthma, is a leading cause of chronic cough, particularly when cough worsens at night, with cold air exposure, or with exercise 4
Gastroesophageal Reflux Disease (GERD) is a major contributor to chronic cough, though acid suppression alone is no longer recommended as sole therapy 1, 3
Nonasthmatic Eosinophilic Bronchitis (NAEB) is an important but less common cause of chronic cough that requires specific identification 1, 2

Atopic cough is more commonly reported in Asian countries as a distinct entity 1, 2
Smoking-related chronic bronchitis can resolve within 4 weeks of cessation in most patients 4
Environmental and occupational exposures should be systematically evaluated in all patients with chronic cough 1, 3

Hemoptysis mandates urgent investigation for life-threatening conditions 1
Smoker >45 years with new cough, change in cough, or coexisting voice disturbance requires immediate evaluation 4
Adults aged 55-80 years with 30 pack-year smoking history who currently smoke or quit within past 15 years should be evaluated for lung cancer 4
Prominent dyspnea, especially at rest or at night, is a red flag for underlying severe disease 4
Systemic symptoms such as fever, weight loss, and night sweats require immediate evaluation 4

Cough hypersensitivity syndrome should be considered as an underlying mechanism in refractory chronic cough 4
Gabapentin trial starting at 300mg once daily, escalating to maximum 1,800mg daily in divided doses, may be effective in refractory chronic cough 4
Multimodality speech pathology therapy is an alternative approach for refractory chronic cough 4

Assuming single etiology of chronic cough, as up to 40% of patients have multiple simultaneous causes requiring combination therapy 1
Using acid suppression alone for GERD-related cough is no longer recommended; comprehensive GERD management is required 1, 3
Ignoring medication review, as ACE inhibitors and sitagliptin must be discontinued before pursuing extensive workup 1, 3, 4
Failing to use validated cough severity tools to objectively assess treatment response 1, 2

Chest radiography is mandatory for every individual presenting with chronic cough to identify potential thoracic pathology, as supported by evidence from Thorax (2006) 5.
Spirometry must be performed in all patients with chronic cough to evaluate for obstructive airway disease, according to data published in Thorax (2006) 6.