Cough: occupational and environmental considerations: ACCP evidence-based clinical practice guidelines.

OBJECTIVES: This section of the guideline aims to review the role of occupational and environmental factors in causing and contributing to cough. It also aims to indicate when such causes should be considered in a clinical setting, and a general approach to assessment and management.

METHODS: A review was performed of published data between 1985 and 2004 using PubMed. The search terms used included "air pollution," "sick building syndrome," "occupational asthma," "occupational lung disease," "hypersensitivity pneumonitis" (HP), "cigarette smoke," and "asthma." Selected articles were chosen when meeting the objectives, but the extent of articles available and the limited space for this section does not permit a fully comprehensive review of all of these areas, for which the reader is referred to other sections of this clinical practice guideline, the published literature, textbooks of occupational lung disease, or more specific review articles.

RESULTS/CONCLUSIONS: Almost any patient presenting with cough may have an occupational or environmental cause of or contribution to their cough. The importance of this is that recognition and intervention may result in full or partial improvement of the cough, may limit the need for medication/symptomatic treatment, and may improve the long-term prognosis. Nonoccupational environmental contributing factors for upper and lower airway causes of cough include indoor irritant and allergenic agents such as cigarette smoke, cooking fumes, animals, dust mites, fungi, and cockroaches. Causes of HP indoors include birds and fungal antigens. Outdoor pollutants and allergens also contribute to upper and lower airway causes of cough. Occupational exposures can cause hypersensitivity responses leading to rhinitis and upper airway cough syndrome, previously referred to as postnasal drip syndrome, as well as asthma, HP, chronic beryllium disease, and hard metal disease, as well as irritant or toxic responses. The diagnosis is only reached by initially considering possible occupational and environmental factors, and by obtaining an appropriate medical history to determine relevant exposures, followed by objective investigations. This may require referral to a center of expertise.