We studied total and specific serum IgE levels cross-sectionally, potential predictors of obstructive lung disease, in a stratified random sample of 18-73-year-old adults (n = 1512). The attendance rate was 84%. The total IgE level and prevalences of specific IgE antibodies against house dust mite and cat were higher for men than for women. Specific IgE levels decreased by increasing age, while total IgE decreased in women only. Smokers had a higher IgE level than non-smokers, while non-smokers had more often specific IgE antibodies against timothy and birch than smokers. Subjects with occupational dust or gas exposure had a higher total IgE level than unexposed. The general population prevalences were for specific IgE antibodies against timothy 4.5%, house dust mite 3.2%, birch 2.6%, cat dander 1.6% mould 0.2% and against any of these 7.6%. In a multivariate analysis age, occupational dust or gas exposure as well as the interaction terms between sex and age and between smoking and pack-years were independent predictors for total IgE levels. Male sex, young age, never having smoked and the season of the year were independent predictors for having one or more of the five specific IgE antibodies. Subjects with total serum IgE in the highest quintile (> or = 66 kU/l) had an adjusted odds ratio of 37 (95% confidence interval: 11-120) for having one or more of the specific IgE antibodies examined, compared with those in the lowest quintile (< 5 kU/l). Demographic and environmental factors were thus predictors of total and specific IgE levels in this adult community.(ABSTRACT TRUNCATED AT 250 WORDS)

Background The importance of occupational exposure to airborne agents in the development of obstructive disease is uncertain. Studying the relation in a community population has the benefit of reducing the healthy worker effect seen in studies of working populations. Methods The prevalence of obstructive lung disease was examined in a Norwegian general population aged 18-73 in a two phased cross sectional survey. In the second phase a stratified sample (n = 1512) of those responding in the first phase was invited for clinical and spirometric examination (attendance rate 84%). Attenders were asked to state all jobs lasting >6 months since leaving school and to say whether they had been exposed to any of seven specific agents and work processes potentially harmful to the lungs. Results The prevalence of asthma and chronic obstructive lung disease was 2-4% and 5 4%, respectively; spirometric airflow limitation (FEVJ/FVC < 0 7 and

Study objective-The aim was to examine causes for non-response in a community survey, and how non-response influences prevalence estimates of some exposure and disease variables, and associations between the variables.Design-This was a cross sectional questionnaire study with two reminder letters. In a postal survey on airborne occupational exposures and lung disorders in Hordaland county, Norway, we examined the causes for non-response, and the characteristics of respondents and nonrespondents. We also wished to investigate how non-response rates may change (1) the estimated prevalences of exposures (smoking and airborne occupational exposure) and lung disorders, and (2) the associations between these exposures and disorders.

The relation of educational level to obstructive lung disease, spirometric airflow limitation, and respiratory symptoms was examined in a two-phase cross-sectional study of a Norwegian general population aged 18-73 years in 1985-1988. The first phase was a questionnaire survey. In the second phase, a stratified sample of those who responded in the first phase was invited to a clinical and respiratory physiologic examination. Altogether, 714 subjects attended, representing 84% of those invited. The prevalences of obstructive lung disease and spirometric airflow limitation were 7.8% and 4.5%, respectively. A total of 18% of the population had completed college, a further 60% had completed secondary school, and 21% had obtained a primary school education alone. The prevalence of both smoking and occupational airborne exposure decreased with increasing educational level. The sex-, age-, smoking-, and occupational exposure-adjusted odds ratio of obstructive lung disease in primary-versus university-educated subjects was 2.9 (95% confidence interval (CI) 1.3-6.5); in secondary- versus university-educated subjects it was 1.4 (95% CI 0.7-2.8). The corresponding values for spirometric airflow limitations were 5.2 (95% CI 2.0-13.4) and 1.8 (95% CI 1.2-2.7). All of the respiratory symptoms except breathlessness grade 2 were significantly associated with educational level after allowing for sex, age, smoking, and occupational airborne exposure. The survey indicates that educational level is a risk factor for airway disorders independent of smoking and occupational airborne exposure.

The objective of this study was to examine how the consistency of self-reported exposure to dust or gas, asbestos, and quartz varied between subjects with and those without respiratory symptoms and asthma in a Norwegian community sample () in 1987-1988. Exposure characterization obtained in a structured work history interview was used as the "gold standard." The authors also wanted to assess how the exposure-disease relation differed when the exposure was based on self-reported versus interview-obtained data. The prevalence of self-reported exposure to dust or gas, asbestos, and quartz was 28%, 5%, and 4%, respectively. The sensitivity of the self-reported exposure data varied from 21% to 64% and was higher in those with than in those without the respiratory disorders. The specificity varied from 78% to 100% and was lower in those with than in those without the respiratory disorders. The sex-, age-, and smoking-adjusted odds ratios of the respiratory disorders in those with exposure to dust or gas and to asbestos were only slightly reduced when misclassification was taken into account. The corresponding numbers for exposure to quartz were halved and lost their statistical significance when the misclassification was allowed for. In this general population sample, the self-reported occupational, airborne exposure data were differentially misclassified by disease status.