Prevalence of respiratory symptoms in Norway

Abstract

Information on respiratory symptoms using a standardized questionnaire was collected by mail from two groups in Norway—a general population sample of persons born 1893–1929 and sibs of migrants to the United States. The general population and sib samples yielded similar findings and were combined for detailed analysis. An excess symptom prevalence among smokers rising with amount smoked, similar to findings reported from other countries, was noted. Persons who started to smoke at young ages and inhalers also presented higher risks. Cigarette smokers exhibited higher prevalence than pipe smokers after adjustment for rate of use, but no differences between hand-rolled and commercial cigarettes were found. Some regional variation not accompanied by important urban-rural differences in symptom prevalence was observed. Urban residence and a high rate of tobacco use did not interact to produce prevalence rates greater than expected from the separate contributions of these two factors. The consistency of the symptom prevalence information with Norwegian mortality data for respiratory diseases is described and some possible implications of the absence of an urban-rural differential or interaction of urban residence with smoking history in the Norwegian data are discussed.