Does Cold Weather Aggravate Dry Cough?
The evidence suggests that cold air itself does not directly cause or worsen dry cough; rather, the association between cold weather and cough is primarily due to increased respiratory infections during winter months and the effects of dry air on airway sensitivity.
Key Evidence Against Cold Air as a Direct Cause
The most compelling evidence comes from high-altitude studies where researchers specifically tested whether cold, dry air causes cough. In controlled hypobaric chamber experiments where temperature and humidity were maintained constant, climbers still developed significant cough at simulated high altitudes, directly refuting the hypothesis that cold, dry air is responsible for altitude-related cough 1. This finding challenges the traditional assumption that cold air directly triggers cough.
What Actually Causes Cough in Cold Weather
Respiratory Infections
- Cold weather is associated with increased viral respiratory tract infections, which are the primary cause of acute cough lasting less than 3 weeks 2, 3
- In European surveys, approximately 20% of patients report non-productive or productive cough during winter months, likely reflecting the seasonal increase in viral infections 1
- The common cold and acute bronchitis account for the vast majority of acute cough cases 3
Pre-existing Respiratory Conditions
For patients with asthma or COPD, cold weather can act as an irritant trigger:
- Environmental irritants and pollutants are important aggravating factors for chronic cough, particularly in patients with underlying airway disease 1
- Exposure to outdoor air pollutants, which can be worse in cold weather due to temperature inversions, may trigger cough in susceptible individuals 1
- However, this represents airway hyperreactivity rather than a direct effect of cold temperature 1
Clinical Implications
For Patients Without Underlying Lung Disease
- If dry cough develops during cold weather without fever, sputum production, or systemic symptoms, consider post-viral cough or increased cough receptor sensitivity rather than attributing it solely to cold exposure 1
- First-generation antihistamines with decongestants may provide symptomatic relief for cough associated with upper respiratory symptoms 1, 4
For Patients With Asthma or COPD
- Cold air exposure can trigger bronchospasm in patients with reactive airway disease, leading to cough as part of an asthma exacerbation 5, 6
- These patients should optimize their controller medications and consider pre-treatment with bronchodilators before cold air exposure 5
- The mechanism is airway hyperresponsiveness, not a direct effect of temperature on cough receptors 6
Common Pitfalls to Avoid
- Do not assume that cough occurring in winter is simply due to "cold air" without evaluating for viral infections, which are far more common 2, 3
- Do not overlook other causes of chronic dry cough (upper airway cough syndrome, asthma, GERD) that may coincidentally worsen during winter months 5
- In patients with persistent dry cough, a systematic evaluation is required regardless of seasonal patterns 1
Bottom Line
Cold weather itself does not directly aggravate dry cough based on controlled experimental evidence 1. The association between cold weather and cough is primarily explained by increased respiratory viral infections during winter months 1, 2 and, in susceptible individuals with asthma or COPD, cold air acting as an airway irritant trigger 1, 5. Treatment should focus on the underlying cause rather than simply attributing symptoms to cold exposure.