Effects of chronic bronchopulmonary disease and aging on human nasal secretion IgA concentrations.

Normal subjects and hospitalized chronically ill patients who did or did not have bronchopulmonary disease were compared according to nasal wash protein and immunoglobulin concentrations. Persons with chronic bronchopulmonary disease were not different from other chronically ill patients in these respects. However, both groups of patients differed statistically from normal subjects in nasal wash IgA concentrations. This difference was accounted for on the basis of decreasing nasal secretion IgA concentration with advancing age. This decrease was considered to represent one of several alterations in immunologic competence associated with aging.