Biomedical subjects

Ursula Ackermann-Liebrich

Publications and source records attributed to Ursula Ackermann-Liebrich.

21 records · Page 2Linked to original sources

PubMed2003

PM2.5 assessment in 21 European study centers of ECRHS II: Method and first winter results.

The follow-up of a cohort of adults from 29 European centers of the former European Community Respiratory Health Survey (ECRHS) I (1989-1992) will examine the long-term effects of exposure to ambient air pollution on the incidence, course, and prognosis of respiratory diseases, in particular asthma and decline in lung function. The purpose of this article is to describe the methodology and the European-wide quality control program for the collection of particles with 50% cut-off size of 2.5 microm aerodynamic diameter (PM2.5) in the ECRHS II and to present the PM2.5 results from the winter period 2000-2001. Because PM2.5 is not routinely monitored in Europe, we measured PM2.5 mass concentrations in 21 participating centers to estimate background exposure in these cities. A standardized protocol was developed using identical equipment in each center (U.S. Environmental Protection Agency Well Impactor Ninety-Six [WINS] and PQ167 from BGI, Inc.). Filters were weighed in a single central laboratory. Sampling was conducted for 7 days per month for a year. Winter mean PM2.5 mass concentrations (November 2000-February 2001) varied substantially, with Iceland reporting the lowest value (5 microg/m3) and northern Italy the highest (69 microg/m3). A standardized procedure appropriate for PM2.5 exposure assessment in a multicenter study was developed. We expect ECRHS II to have sufficient variation in exposure to assess long-term effects of air pollution in this cohort. Any bias caused by variation in the characteristics of the chosen monitoring location (e.g., proximity to traffic sources) will be addressed in later analyses. Given the homogenous spatial distribution of PM2.5, however, concentrations measured near traffic are not expected to differ substantially from those measured at urban background sites.

Air Pollutants↗

PubMed2002

Predictors of methacholine responsiveness in a general population.

OBJECTIVE: Methacholine responsiveness is an end point widely used in epidemiologic studies of asthma. This study aims to quantify the relative importance of different predictors of responsiveness such as age, sex, airway caliber, smoking and atopic status, and potential interactions deserving further investigation. METHODS: Methacholine challenge was performed in 7,126 participants (aged 18 to 60 years) of the Swiss Study on Air Pollution and Lung Diseases in Adults according to the European Respiratory Health Survey protocol. Responsiveness was quantified by the slope between percentage decrements in FEV(1) and cumulative methacholine dose. Variation of slopes according to sex, smoking, and atopy was then examined separately by multivariate regression models that controlled for baseline FEV(1). RESULTS: We found a nonlinear relationship between methacholine slope and baseline FEV(1) for both sexes, which could be well described by a quadratic function. The corresponding curves were almost identical in the region of overlap for male and female neversmokers. Methacholine responsiveness declined with age. The slope of this decline was less steep among nonatopic persons and nonsmokers compared with atopic neversmokers. Methacholine responsiveness increased with the number of cigarettes smoked per day and with the number of positive skin-prick test results (except among heavy smokers). CONCLUSIONS: Our multiple regression results show that bronchial responsiveness (BR) varies with age, FEV(1), and smoking and atopic status. They suggest that there is a physiologic basis for the univariate sex difference in BR. Secondly, they show that while smaller airways are more responsive than larger ones, the reduction of responsiveness diminishes with each increase of lung size. The quantification of the relative influence of the different factors examined should help in the interpretation of BR.

Adolescent↗

PubMedDate not supplied

Smoking cessation, lung function, and weight gain: a follow-up study.

BACKGROUND: Only one population-based study in one country has reported effects of smoking cessation and weight change on lung function, and none has reported the net effect. We estimated the net benefit of smoking cessation, and the independent effects of smoking and weight change on change in ventilatory lung function in the international European Community Respiratory Health Survey. METHODS: 6654 participants in 27 centres had lung function measured in 1991-93, when aged 20-44 years, and in 1998-2002. Smoking information was obtained from detailed questionnaires. Changes in lung function were analysed by change in smoking and weight, adjusted for age and height, in men and women separately and together with interaction terms. FINDINGS: Compared with those who had never smoked, decline in FEV1 was lower in male sustained quitters (mean difference 5.4 mL per year, 95% CI 1.7 to 9.1) and those who quit between surveys (2.5 mL, -1.9 to 7.0), and greater in smokers (-4.8 mL, -7.9 to -1.6). In women, estimates were 1.3 mL per year (-1.5 to 4.1), 2.8 mL (-0.8 to 6.3) and -5.1 mL (-7.5 to -2.8), respectively. These sex differences were not significant. FEV1 changed by -11.5 mL (-13.3 to -9.6) per kg weight gained in men, and by -3.7 mL per kg (-5.0 to -2.5) in women, which diminished the benefit of quitting by 38% in men, and by 17% in women. INTERPRETATION: Smoking cessation is beneficial for lung function, but maximum benefit needs control of weight gain, especially in men.

Adult↗