Essential Elements of a Respiratory History
A comprehensive respiratory history must systematically address duration of symptoms, red flag features, smoking/occupational exposures, and associated symptoms to guide appropriate investigation and avoid missing serious pathology.
Duration and Timing of Symptoms
Establish the exact duration of cough in weeks to categorize as acute (<3 weeks), subacute (3-8 weeks), or chronic (>8 weeks), as this fundamentally determines the diagnostic approach and most likely etiologies 1.
Document whether onset was sudden or gradual, and whether symptoms are worsening, stable, or improving 1.
Ask about diurnal variation: nocturnal cough may suggest asthma, heart failure, or infection, while cough that abates overnight may indicate gastroesophageal reflux 2.
Determine if cough is paroxysmal in nature to help differentiate between potential causes 1.
Red Flag Symptoms Requiring Urgent Investigation
The following features mandate immediate evaluation for serious pathology:
Hemoptysis - investigate immediately for malignancy or tuberculosis 2, 1.
Unintentional weight loss - may indicate malignancy or tuberculosis 1.
Fever or prominent systemic illness - assess for serious acute lung infection 2, 1.
Sudden onset with suspicion of inhaled foreign body - specialist referral for bronchoscopy is mandatory 2.
Voice change - may indicate vocal cord palsy 2.
Smoking History
Quantify tobacco use in pack-years, as smoking is responsible for 85-90% of chronic bronchitis cases and is dose-related 1.
Document current smoking status and years since quitting if former smoker 1.
Note that smoking is one of the commonest causes of persistent cough 2.
Occupational and Environmental Exposure History
This is essential when respiratory disease is suspected 2.
Obtain comprehensive occupational history including current and past jobs, specific tasks performed, and duration of exposure 2, 1.
Emphasize exposures occurring 15 years or more before presentation, as asbestos-related disease requires appropriate latency period 2.
Ask specifically about exposure to dust, chemicals, fumes, hot acidic conditions, or respiratory irritants 1.
Representative high-risk occupations include: asbestos product manufacturing, mining and milling, construction trades (insulators, sheet metal workers, electricians, plumbers, pipefitters, carpenters), power plant workers, boilermakers, and shipyard workers 2.
Note that occupational titles alone are insufficient - "millwright," "fireman," or "mixer" may be uninformative without detailed task description 2.
Remember that "bystander" exposure can occur in workers whose own jobs don't require handling hazardous materials but who work in proximity to other users 2.
Sputum Production
Quantify daily sputum production, as significant sputum (>30 mL/day) usually indicates primary lung pathology 1, 3.
Ask if productive cough occurs most days for ≥3 months over ≥2 consecutive years to define chronic bronchitis 1.
Document color, consistency, and any changes in sputum character 3.
Medication History
Ask specifically about ACE inhibitor use, as it's a common and easily reversible cause of cough 1.
ACE inhibitor-associated cough can occur within hours to over a year after starting treatment and typically resolves within 26 days after discontinuation 1.
Associated Respiratory Symptoms
Upper Airway Symptoms
- Ask about postnasal drip sensation or frequent throat clearing to identify upper airway cough syndrome 1.
Lower Airway Symptoms
Document dyspnea characteristics: insidious onset of dyspnea on exertion is the most common symptom associated with asbestosis 2.
Ask about wheezing or chest tightness to identify asthma or eosinophilic bronchitis 1.
Acute cough with increasing breathlessness should be assessed for asthma or anaphylaxis 2.
Gastrointestinal Symptoms
Ask about heartburn or acid regurgitation to identify gastroesophageal reflux disease 1.
Note that absence of dyspepsia does not rule out reflux as cause of cough 2.
Chest Pain
In patients with diffuse pleural thickening or fibrothorax, dyspnea on exertion occurs in 95% and chest pain in more than half 2.
Rapidly progressive or severe chest pain should raise suspicion of malignancy or nonmalignant pleuritis 2.
Past Medical History
Ask about history of asthma, COPD, or bronchiectasis, as these commonly present with or are exacerbated by cough 1.
Document previous pneumonia, tuberculosis, or pertussis infection 1.
COPD-Specific History Elements
For suspected COPD, the diagnosis requires three features 2:
Appropriate symptoms including dyspnea, chronic cough, sputum production, or wheezing 2.
Significant exposures to noxious stimuli (typically ≥10 pack-years of smoking, though GOLD does not specify exact quantification) 2.
Confirmation with post-bronchodilator spirometry showing FEV1/FVC <0.70 2.
Impact Assessment
Use validated cough severity assessment tools such as cough-specific quality of life questionnaires (Leicester Cough Questionnaire or Cough Specific Quality of Life Questionnaire) or visual analogue scales 1.
Assess impact on sleep quality and frequency of nocturnal awakening 1.
Determine effect on work productivity and social activities 1.
Quality of life is significantly impaired in both acute and chronic cough, with psychological aspects particularly affected in chronic cough 2.
Common Pitfalls to Avoid
Do not rely on occupational title alone - detailed task description is essential for exposure assessment 2.
Do not assume absence of dyspepsia rules out GERD as a cause of cough 2.
Patients may forget short periods of employment during which intense exposure occurred, or employment early in their lives 2.
Subjective symptoms require objective findings for interpretation but provide important ancillary information about future risk 2.
The character and timing of cough have limited diagnostic specificity, though some patterns may suggest specific etiologies 2.