Incidence rate of adult-onset asthma in relation to age, sex, atopy and smoking: a Swedish population-based study of 15813 adults.

SETTING: Our knowledge about asthma incidence in an adult population is limited. The aim of the present investigation was to estimate the incidence rate of adult-onset asthma in relation to age, sex, atopy and smoking in a random population sample. METHODS: A random sample of 20000 subjects 20 to 50 years of age was investigated using a short respiratory questionnaire. It was answered by 15813 persons. Adult-onset asthma was defined as a positive response to 'physician-diagnosed' asthma from 16 years of age. Subjects were also asked to report the year of asthma diagnosis, and also, when relevant, the year of smoke-start and smoke-stop. Incidence rates of adult-onset asthma and incidence rate ratios (IRR) were calculated. RESULTS: The incidence rate of adult-onset asthma among females was 1.3 cases/1000 person-years compared with 1.0/1000 person-years for males (IRR 1.3, 95% confidence interval [CI] 1.0-1.6). The incidence rate was high (3.0/1000 person-years) among females aged 16-20 years. There was a strong association between the incidence rate of adult-onset asthma and hay fever, atopic dermatitis and family history of atopy. Compared with never-smokers, the IRR for female smokers was 1.6 (95% CI 1.1-2.2), while for male smokers it was unity. Both male and female ex-smokers had moderately increased rate ratios, of 1.5 and 1.1, respectively. CONCLUSIONS: In this retrospective study, reported atopic symptoms and family history of atopy were strongly associated with incidence of adult-onset asthma. Tobacco smoking may be associated with an increased incidence rate of adult-onset asthma, especially among women.

Rhinitis increase the risk for adult-onset asthma--a Swedish population-based case-control study (MAP-study).

The aim of the study was to examine certain predictors, especially non-infectious rhinitis, and the risk for adult-onset asthma. A nested case-control study of adult-onset asthma was performed in a random sample from the general population (n = 15,813), aged 21 to 51 years. Cases for the study included subjects reporting physician-diagnosed asthma (n = 235) and controls (n = 2044) were randomly selected from the whole population sample. The case-control sample was investigated with a comprehensive respiratory questionnaire. Odds ratios were calculated stratified for sex, year of diagnosis and birth-year. Adult-onset physician-diagnosed asthma was associated with occurrence of non-infectious rhinitis before asthma onset (OR = 5.4, 95% CI 4.0-7.2), especially among smoking non-atopics (OR = 9.1, 95% CI 5.3-15.4). Smoking before asthma onset increased the risk for asthma (OR = 1.5, 95% CI 1.1-2.1). In conclusion, this population-based case-control study indicate that non-infectious rhinitis and current smoking, especially among non-atopics, are associated with increased risk for adult-onset asthma.

Adult-onset asthma and occupational exposures.

OBJECTIVES: This study examined certain occupational exposures and the risk for adult-onset asthma. METHODS: A nested case-referent study of adult-onset asthma was performed on a random population sample (N=15813), aged 21 to 51 years. Cases for the study included 2 groups: subjects reporting "physician-diagnosed" asthma (N=251) and a broader "asthma" group (N=362). The "asthma" group consisted of subjects with "physician-diagnosed" asthma (N=251) and subjects reporting asthma-like symptoms without having "physician-diagnosed" asthma (N=111). The referents (N=2044) were randomly selected from the whole population sample. The case-referent sample was investigated with a comprehensive questionnaire about occupational exposures, asthma, respiratory symptoms, smoking, and atopy. Odds ratios were calculated with stratification for gender, year of diagnosis, and birth year. RESULTS: The highest odds ratio for "physician-diagnosed" asthma was associated with exposure to flour dust [odds ratio (OR) 2.8, 95% confidence interval (95% CI) 1.5-5.2] and the occupational handling of resin-based paints (isocyanates) (OR 3.0, 95% CI 1.6-5.9). Exposure to welding fumes, textile dust, and work with glues containing acrylates was also associated with an increased odds ratio for "physician-diagnosed" asthma. Including persons with asthma-like symptoms (ie, the asthma group) showed similar results. CONCLUSION: This population-based case-referent study from Sweden indicates that occupational exposure to acrylate-based compounds and welding fumes is associated with increased risk for adult-onset asthma.

A 4-week comparison of salmeterol and terbutaline in adult asthma.

This was a 4-week, open-label, parallel-group study designed to compare the efficacy and safety of the long-acting inhaled bronchodilator, salmeterol, with the established inhaled bronchodilator, terbutaline, in the treatment of patients with mild to moderate asthma. A total of 243 adult patients was randomized to receive treatment with either salmeterol 50 micrograms bd via a Diskhaler (Glaxo) inhaler (n = 121) or terbutaline 500 micrograms qds via a reservoir powder inhaler device (n = 122). Apart from all bronchodilator treatment which was withdrawn at the start of the run-in period and replaced by inhaled salbutamol to be used as required for symptom relief, all concurrent medications were kept constant throughout the study. Salmeterol produced a significantly greater increase in mean morning peak expiratory flow (PEF) than terbutaline (difference in adjusted means after treatment = 28 l/min; 95% CI = 19-37 l/min; P < 0.001). Likewise, the increase in mean evening PEF was significantly greater following treatment with salmeterol than with terbutaline (difference in adjusted means = 9 l/min; 95% CI = 0-17 l/min; P = 0.045). Salmeterol was associated with a significant reduction in diurnal variation in PEF by comparison with terbutaline (difference in adjusted means = -18 l/min; 95% CI = -24, -12 l/min; P < 0.001). Significant improvements with salmeterol by comparison with terbutaline were also observed in daytime and night-time asthma scores, percentage of symptom-free days and nights, use of additional inhaled bronchodilator, and percentage of days and nights when no additional inhaled bronchodilator was needed.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of dose-response effects of inhaled beclomethasone dipropionate and budesonide in the management of asthma.

The dose-response effects of inhaled beclomethasone dipropionate (BDP) and budesonide (BUD) administered b.i.d. with the aid of metered dose aerosols were studied in 128 patients (67 men and 61 women, mean age 53 years) suffering from asthma bronchiale. The study was designed as a multi-centre, double-blind, four-period cross-over study, followed by a single-blind double placebo period. BDP was administered in doses of 400 and 1000 micrograms, and BUD in doses of 400 and 800 micrograms. The results in terms of peak expiratory flow (PEF) in the morning and evening, daily symptoms score and use of inhaled beta 2-agonists did not reveal any clinically significant differences between the drugs or between high (800 micrograms BUD, 1000 micrograms BDP) and low (400 micrograms BUD/BDP) doses. However, statistically significant differences were recorded for the corresponding parameters when comparing the placebo with preceding steroid periods. Adverse effects consisting mainly of oropharyngeal candidiasis, hoarseness and cough occurred in 54 of 468 treatment months (12%). The carry-over effects of inhaled steroids are longer lasting than was previously assumed.