James F. Potts ^1*, Roberto J. Rona ², Manuel J. Oyarzun ³, Hugo Amigo ⁴, Patricia Bustos ⁴

¹ Imperial College London, National Heart and Lung Institute
² King's College London, Division of Asthma, Allergy and Lung Biology
³ University of Chile, Institute of Bio-medical Science
⁴ University of Chile, Department of Nutrition

^* To whom correspondence should be addressed. E-mail: j.potts{at}imperial.ac.uk.

	Abstract

Objectives. We assessed the effects of indoor risk factors, including smoking, on different types of cough and on cough and wheeze in combination.

Methods. Our sample was composed of 1232 men and women residing in a semirural area of Chile. We used a standardized questionnaire, sensitization to 8 allergens, and bronchial hyperresponsiveness to methacholine to assess cough and wheeze characteristics. Information was gathered on dampness, mold, ventilation, heating, housing quality, smoking, and environmental tobacco smoke exposure.

Results. Most exposures were associated with cough alone or cough in combination with wheeze. Smoking, past smoking, and environmental tobacco smoke exposure were strongly associated with dry cough and wheeze. The use of coal for heating was associated with dry cough. Leaks, mold, and lack of kitchen ventilation were associated with cough and wheeze. Nocturnal cough and productive cough were associated with specific types of sensitization, but dry cough was not. Productive cough was associated with hyperresponsiveness to methacholine.

Conclusions. Several different types of indoor exposures, including environmental tobacco smoke exposure, are important contributors to morbidity associated with cough and wheeze. A vigorous preventive strategy designed to lower exposures to indoor risk factors would lower rates of respiratory morbidity.

Key Words: Epidemiology, Asthma, Respiratory Health, Environmental Tobacco Smoke, Tobacco