The study used the population and data base of the Veterans Administration Normative Aging Study (NAS) which began in 1963. The NAS population consists of over 1,900 men originally selected for good health and their wives. The NAS currently administers a cigarette smoking history questionnaire, the NHLBI-ATS respiratory symptom and illness questionnaire, and spirometry at regularly scheduled examinations three years apart. The current study assessed airways responsiveness as measured by response to methacholine inhalation and atopy as measured by skin test, blood eosinophilia, and serum IgE in NAS participants when they returned for their next two examinations. The data were used to examine the relationship of airways responsiveness, atopy, and cigarette smoking to respiratory symptoms both cross-sectionally and longitudinally.