Variation in bronchial responsiveness in the European Community Respiratory Health Survey (ECRHS)

Abstract

Attempts to compare bronchial responsiveness between populations have been hampered by between-study differences in the pharmacological agent of provocation, the method of administration and the summary statistic employed. The European Community Respiratory Health Survey used methacholine challenge delivered by Mefar dosimeter according to a standardized protocol used in 35 centres in 16 countries.Data were obtained from 13,161 men and women, aged 20-44 yrs at the start of the study. The dose of methacholine producing a 20% fall in forced expiratory volume in one second (FEV1) (PD20) and the regression coefficient of percentage decline in FEV1 with log dose, were calculated ("slope", after transformation), with and without calibration of nebulizers by weight and adjustment for nonresponse bias. Standardization for baseline lung function and variation in smoking prevalence was applied to slope.Results were robust to whichever summary measure was used, and to the various adjustments. Responsiveness was low in Iceland and Switzerland, and in most centres in Sweden, Italy and Spain, and high in New Zealand, Australia, the USA, Britain, France, Denmark and Germany.Bronchial responsiveness varies considerably in Europe, and high levels are not confined to the English-speaking world. Eur Respir J 1997; 10: 2495-2501 Bronchial challenge has been used for over 20 yrs, and there have been several epidemiological studies of risk factors for bronchial responsiveness. However, there are relatively few prevalence studies in the general population, and most of these have been in Englishspeaking countries. NEUKIRCH and CARTIER [1] identified 12 studies, eight using histamine challenge, three methacholine and one cold air, with a variety of cut-off points to define reactivity, and differing age ranges. Two comparative studies in children have been published [2,3], one involving four countries and one involving two, but to date no comparative data on adults from different countries have been reported.The European Community Respiratory Health Survey (ECRHS) is a multicentre study of the variation in the prevalence, risk factors and management of asthma throughout the European Union and elsewhere [4], and includes measurement of bronchial response to methacholine challenge. Results are reported here from 35 centres in 16 countries which have provided usable data. Methods SamplingThe protocol for the ECRHS has been described in detail elsewhere [4,5]. Briefly, participating centres selected an area defined by pre-existing administrative boundaries, with a population of at least 150,000 people. Where possible an up-to-date sampling frame was used to select randomly at least 1,500 men and 1,500 women aged 20-44 yrs. In stage 1 subjects were sent a questionnaire enquiring about respiratory symptoms and attacks of asthma in the last 12 months, current use of asthma medication and nasal allergies including hayfever. A random sample of subjects were selected to take part in stage 2. Those who had already responded to stage 1 wer...

Health in early adulthood: the contribution of the 1978/79 Ribeirão Preto birth cohort

“…The data revealed a high prevalence of asthma and bronchial hyperresponsiveness, detected in few parts of the world (15). The fact that asthma and hyperresponsiveness rates were higher among women is not surprising since this is a finding frequently reported in other studies (39).…”

Apparent but not real increase in asthma prevalence during the 1990s

“…They are potentially important, as the presence of respiratory symptoms is a recognised determinant of participation in such studies [26]. To the present authors9 knowledge, the current study is the first repeat survey of a population following the ECRHS template and so the repeatability of the methodology is unknown.…”

Paracetamol sales and atopic disease in children and adults: an ecological analysis

“…It has been noted previously that centres in Englishspeaking Western countries in the International Study of Asthma and Allergies in Childhood and the European Community Respiratory Health Survey tend to have some of the highest prevalences of atopic symptoms, bronchial responsiveness and atopy, a phenomenon which has hitherto been unexplained [1,17,18,25]. Interestingly, these countries also appear to have some of the highest paracetamol sales (>20 g .…”

“…In phase 2, random samples of phase 1 respondents from some of the centres were assessed in greater detail. A smoking history was obtained, spirometry and bronchial challenge with methacholine (35 centres) were carried out [17], and total and specific immunoglobulin E (IgE) levels (37 centres) were measured [18]. Bronchial responsiveness was measured as a methacholine dose/response "slope", expressed in ECRHS units [17].…”

“…A smoking history was obtained, spirometry and bronchial challenge with methacholine (35 centres) were carried out [17], and total and specific immunoglobulin E (IgE) levels (37 centres) were measured [18]. Bronchial responsiveness was measured as a methacholine dose/response "slope", expressed in ECRHS units [17]. (On this scale, zero represents the highest possible responsiveness, 10 represents no responsiveness and scores of >10 are assigned to patients whose airways appear to relax (instead of constricting) in response to methacholine.)…”