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U Keil

Publications and source records attributed to U Keil.

At least 55 records · Page 3Linked to original sources
PubMed2000

Exposure to high concentrations of nitrosamines and cancer mortality among a cohort of rubber workers.

OBJECTIVES: To examine if the occurrence of different cancers was increased among rubber workers, as the highest known exposures of humans to nitrosamines have occurred in the rubber industry. METHODS: A cohort of 8933 rubber workers (hired after 1 January 1950, still active or retired on 1 January 1981 and employed for at least 1 year in one of five study factories) was followed up for mortality from 1 January 1981 to 31 December 1991. Work histories were reconstructed with routinely documented cost centre codes, which allowed identification by employment in specific work areas. For each cost centre code time and factory specific, semi-quantitative exposures to nitrosamines (three levels: low, medium, high) and other compounds were estimated by industrial hygienists. Rate ratios for medium (RRm) and high (RRh) exposures and 95% confidence intervals (95% CIs) were calculated with Cox's proportional hazards models with the low exposure as reference. RESULTS: Exposure to nitrosamines was significantly associated with an increased mortality from cancers of the oesophagus (13 deaths: RRm 1.7, 95% CI 0.3 to 10.3; RRh 7.3, 95% CI 1.9 to 27.8) and of the oral cavity and pharynx (17 deaths: RRm 0.8, 95% CI 0.2 to 4.1; RRh 3.9, 95% CI 1.4 to 11.1). A non-significant trend of increasing mortality with exposure to higher concentrations of nitrosamines was found for mortality from cancer of the prostate (26 deaths: RRm 1.4, 95% CI 0.5 to 3.8; RRh 2.2, 95% CI 0.9 to 5.6), and the brain (six deaths: RRm 3.9, 95% CI 0.3 to 42.6; RRh 6.0, 95% CI 0.6 to 57.6). No association was found between exposure to nitrosamines and cancer of the stomach (RRm 0.8, 95% CI 0.4 to 1.8; RRh 1.2, 95% CI 0.5 to 2.5) or lung (RRm 1.0, 95% CI 0.6 to 1.5; RRh 1.0, 95% CI 0.7 to 1.6). CONCLUSIONS: Exposure to high concentrations of nitrosamines is associated with increased mortality from cancers of the oesophagus, oral cavity, and pharynx, but not with increased mortality from cancers of the stomach or lung.

Adult↗
PubMed2000

Comparison of asthma prevalence in the ISAAC and the ECRHS. ISAAC Steering Committee and the European Community Respiratory Health Survey. International Study of Asthma and Allergies in Childhood.

International and regional prevalence comparisons are required to test and generate hypotheses regarding the causes of increasing asthma prevalence in various age groups worldwide. The International Study of Asthma and Allergies in Childhood (ISAAC) is the first such study in children and the European Community Respiratory Health Survey (ECRHS) is the first such study in adults. Therefore, a comparison of the findings of these two surveys was conducted, for the 17 countries in which both surveys were undertaken. There was a strong correlation between the ISAAC and ECRHS prevalence data, with 64% of the variation at the country level, and 74% of the variation at the centre level, in the prevalence of "wheeze in the last 12 months" in the ECRHS phase I data being explained by the variation in the ISAAC phase I data. There was also generally good agreement in the international patterns observed in the two surveys for self-reported asthma (74% of country level and 36% of centre level variation explained), self-reported asthma before age 14 yrs (64 and 26%), hay fever (61 and 73%) and eczema (41 and 50%). Thus although there were differences in the absolute levels of prevalence observed in the two surveys, there is good overall agreement between the International Study of Asthma and Allergies in Childhood and European Community Respiratory Health Survey study findings with regard to international prevalence patterns. These findings, therefore, add support to the validity of the two studies, which provide a new picture of global patterns of asthma prevalence from child- to adulthood, and identify some of the key phenomena which future research must address.

Adolescent↗
PubMed1999

Elevated mortality from nonalcohol-related chronic liver disease among female rubber workers: is it associated with exposure to nitrosamines?

BACKGROUND: Despite several case reports describing liver toxicity of nitrosamines and the fact that some N-nitroso compounds are used to induce cirrhosis of the liver in animal models, this association has not been investigated in epidemiological studies. METHODS: A cohort of 2,875 female rubber workers who were active on January 1, 1976, or hired thereafter, and who had been employed for at least 1 year in one of five plants producing tires or technical rubber goods was followed for mortality from January, 1976, through December, 1991. Work histories were reconstructed using routinely documented "cost center codes" and classified into six work areas. Age and calendar year standardized mortality ratios (SMR) and 95% confidence intervals (95% CI) were calculated and stratified by plant, work area, year of hire, and years of employment in the respective work area. RESULTS: The excess mortality from cirrhosis of the liver was most pronounced for nonalcohol-related cirrhosis of the liver (ICD-9 571.4-571.9: 10 deaths, SMR 202; 95% CI 97-372). Mortality from alcohol-related cirrhosis of the liver (ICD-9 571.0-571.3: 3 deaths, SMR 153; 95% CI 31-446) and from other alcohol-related diseases (organic psychoses, injury, and poisoning) was not statistically significantly elevated. All 10 cases of nonalcohol-related cirrhosis had worked in production of technical rubber goods (SMR 279; 95% CI 134-514) and risks increased with earlier years of hire and with longer duration of employment in this work area. DISCUSSION: Although our results must be interpreted with caution, they suggest that the observed excess deaths from cirrhosis of the liver are associated with occupational risk factors. In light of additional evidence from case reports and animal data, exposure to nitrosamines may be a plausible risk factor for the observed excess mortality.

Adult↗
PubMed1999

Meal patterns in middle-aged men in Southern Germany: results from the MONICA Augsburg dietary survey 1984/85.

Seven-day food records of the MONICA project Augsburg dietary survey, which were collected in 1984/85 from 899 men aged 45-64 years (random sample), were used to analyse meal patterns. The combination of the three traditional meals (breakfast, lunch, dinner) with one eating event between was most frequent, followed by two meals with two eating events between and three main meals without any other eating event (31.4 vs. 31.0 vs. 15.6% of all reported days). Breakfast delivered 17, lunch 29 and dinner 33% of the total daily energy intake; all other eating events delivered 21%. The mean contribution of the three meals, breakfast, lunch and dinner to daily protein intake was 14, 36 and 36%, to fat intake 17, 33 and 35% and to carbohydrate intake 23, 25 and 29%, respectively. Data on meal patterns are important in a comprehensive description of dietary habits of a population for a variety of reasons.

Diet↗
PubMed1999

Worldwide variations in the prevalence of symptoms of atopic eczema in the International Study of Asthma and Allergies in Childhood.

BACKGROUND: Little is known about the prevalence of atopic eczema outside Northern Europe. OBJECTIVES: We sought to describe the magnitude and variation in the prevalence of atopic eczema symptoms throughout the world. METHODS: A cross-sectional questionnaire survey was conducted on random samples of schoolchildren aged 6 to 7 years and 13 to 14 years from centers in 56 countries throughout the world. Those children with a positive response to being questioned about the presence of an itchy relapsing skin rash in the last 12 months that had affected their skin creases were considered to have atopic eczema. Children whose atopic eczema symptoms resulted in sleep disturbance for 1 or more nights per week were considered to have severe atopic eczema. RESULTS: Complete data was available for 256,410 children aged 6 to 7 years in 90 centers and 458,623 children aged 13 to 14 years in 153 centers. The prevalence range for symptoms of atopic eczema was from less than 2% in Iran to over 16% in Japan and Sweden in the 6 to 7 year age range and less than 1% in Albania to over 17% in Nigeria for the 13 to 14 year age range. Higher prevalences of atopic eczema symptoms were reported in Australasia and Northern Europe, and lower prevalences were reported in Eastern and Central Europe and Asia. Similar patterns were seen for symptoms of severe atopic eczema. CONCLUSIONS: Atopic eczema is a common health problem for children and adolescents throughout the world. Symptoms of atopic eczema exhibit wide variations in prevalence both within and between countries inhabited by similar ethnic groups, suggesting that environmental factors may be critical in determining disease expression. Studies that include objective skin examinations are required to confirm these findings.

Adolescent↗
PubMed1999

Population trends in antihypertensive drug use: results from the MONICA Augsburg Project 1984 to 1995.

Trends in antihypertensive drug use were assessed among 25- to 64-year-old participants of three independent surveys of the MONICA Augsburg region in 1984/85, 1989/90, and in 1994/95. Despite constant prevalences of hypertension, the percentage of hypertensives taking medication increased over the study period. The latter was mainly due to significant rises in antihypertensive monotherapy. By contrast, the use of combination treatments with two or more agents remained constant; however, although combinations composed of only two drugs were taken more often in 1995, those with three or more agents and fixed-dose preparations decreased substantially. Beta-blockers were most frequently, and with a rising tendency, taken as antihypertensive monotherapy. Newer drug classes like calcium channel blockers and ACE-inhibitors were introduced as monotherapy more hesitantly. Diuretics persisted as the basis of antihypertensive combination therapy. The use of combination therapies containing obsolete drugs, like reserpine, declined significantly with corresponding increases in drug combinations of, in particular, calcium channel blockers or ACE-inhibitors. We conclude that monotherapies account for most of the rising antihypertensive treatment rates and probably reflect intensified therapy of borderline hypertensives. The trends in antihypertensive drug classes and treatment regimens reflect a less rapid adoption of novel therapeutic concepts but a fairly close adherence to national and international guidelines.

Adult↗
PubMed1999

Frequency of infections and risk of asthma, atopy and airway hyperresponsiveness in children.

The role of repeated infections early in life in the development of childhood asthma and allergies has not been clarified. The aim of this study was to investigate the effect of repeated episodes of fever and antibiotic treatments during the first years of life on the prevalence of asthma, bronchial hyperresponsiveness (BHR), and atopy at school age in a representative population. Random samples of schoolchildren aged 5-7 yrs (n=7,545) and 9-11 yrs (n=7,498) were studied using the International Study of Asthma and Allergies in Childhood (ISAAC) phase II protocol. To assess the prevalence of disease and early childhood exposures, parental questionnaires were administered (response rates 82.2% and 85.3%, respectively). In addition, children underwent skin prick tests, hypertonic saline challenge and blood sampling for the measurement of serum immunoglobulin (Ig)E. Repeated episodes of fever and antibiotic treatment in early life were strongly associated with the prevalence of asthma (odds ratio (OR)=7.95; 95% confidence interval (CI) 6.02-10.50) and current wheeze at school age. Within asthmatic children the number of fever episodes and antibiotic courses were strongly inversely related to the prevalence of atopy (OR=0.25; 95% CI 0.11-0.54 for skin test reactivity) and BHR (OR=0.31; 95% CI 0.10-0.92). Furthermore, asthmatic children with recurrent early childhood infections were at a lower risk of being symptomatic at school age. When considering atopic and nonatopic asthmatic children separately, the highest risk of asthma with repeated early childhood infections was found for nonatopic asthma (OR=24.29; 95% Cl 11.86-49.76). These findings suggest that a subgroup of children with a triggering or inducing of asthmatic symptoms through repeated early childhood infections exists within the "asthma syndrome" which has a better prognosis and is less related to the atopic phenotype.

Adolescent↗
PubMed1999

Inner city air pollution and respiratory health and atopy in children.

The impact of inner city air pollution on the development of respiratory and atopic diseases in childhood is still unclear. In a cross sectional study in Dresden, Germany, 5,421 children in two age groups (5-7 yrs and 9-11 yrs) were studied according to the International Study of Asthma and Allergies in Childhood (ISAAC) phase II protocol. The prevalences of wheezing and cough as well as doctor diagnosed asthma and bronchitis were assessed by parental questionnaires. Children also underwent skin-prick testing, venipuncture for the measurement of serum immunoglobulin (Ig)E, lung function testing and a bronchial challenge test (4.5% saline) to assess airway hyperresponsiveness. Exposure was assessed on an individual basis by relating mean annual air pollution levels (SO2, NO2, CO, benzene, and O3) which had been measured on a 1 km2 grid, to the home and school address of each study subject. After adjusting for potential confounding factors an increase in the exposure to benzene of 1 microg x m3 air was associated with an increased prevalence of morning cough (adjusted odds ratio (aOR)): 1.15; 1.04-1.27) and bronchitis (aOR: 1.11; 1.03-1.19). Similar associations were observed for NO2 and CO. In turn, the prevalences of atopic sensitization, symptoms of atopic diseases and bronchial hyperresponsiveness were not positively associated with exposure to any of these pollutants. It is concluded that in this study a moderate increase in exposure to traffic-related air pollution was associated with an increased prevalence of cough and bronchitis, but not with atopic conditions in children.

Air Pollution↗
PubMed1999

Prevalence of respiratory and atopic disorders among children in the East and West of Germany five years after unification.

Living conditions in eastern Germany have changed rapidly since unification in 1990 and little is known about how these changes affect the prevalence of atopic diseases. This study describes methods and prevalences of a large epidemiological project investigating determinants of childhood asthma and allergies in eastern (Dresden and Leipzig) and western (Munich) Germany in 1995/1996. Community based random samples of 9-11 yr old children in Dresden (n=3,017) and Munich (n=2,612), and of 5-7 yr old children in Dresden (n=3,300), Leipzig (n=3,167) and Munich (n=2,165) were studied by parental questionnaires, bronchial challenges with hypertonic saline, skin examination, skin-prick tests, and measurements of specific and total serum immunoglobulin (Ig)E using Phase II modules of the International Study of Asthma and Allergies in Childhood (ISAAC). In 9-11 yr old children, the prevalence of physician diagnosed asthma (7.9% versus 10.3%; p<0.01) and bronchial hyperresponsiveness (15.7% versus 19.9%; p<0.05) was lower in Dresden than in Munich. No difference between Munich and Dresden was observed in the prevalence of diagnosed hay fever, skin test reactivity to > or = 1 allergen, and increased levels (>0.35 kU x L(-1)) of specific IgE against inhalant and food allergens. Symptoms and visible signs of atopic eczema tended to be more prevalent in Dresden. Similar East-West differences between the three study areas were seen in the younger age group. These findings are in line with recently observed increases in the prevalence of hay fever and atopic sensitization, but not of asthma and bronchial hyperresponsiveness, among 9-11 yr old children in Leipzig.

Air Pollution↗
PubMed1999

Occupational risk factors for mortality from stomach and lung cancer among rubber workers: an analysis using internal controls and refined exposure assessment.

OBJECTIVES: To determine occupational risk factors for stomach and lung cancer among workers in the German rubber industry. METHODS: A cohort of all male German rubber workers (n = 11,633) who had been employed for at least one year in one of five study plants and who were alive and actively employed or retired on 1 January 1981 was followed for mortality from 1 January 1981 through December 1991. A subcohort of n = 8,933 workers who were hired after 1 January 1950 was defined to focus on working conditions in the more recent rubber industry. Work histories were reconstructed using routinely documented 'cost centre codes' and classified into six work areas as well as subgroups of some work areas. The work areas are: 1. preparation of materials, 2. production of technical rubber goods, 3. production of tyres, 4. storage and dispatch, 5. maintenance, 6. others. Standardized mortality ratios (SMR) and Cox proportional hazards models were calculated for each of the work areas (>1 year of employment in the respective work area). Hazard rate ratios were adjusted for age (time marker) and stratified for year of hire (1950-1959, > or =1960) and years of employment in the respective work area (1-9 years, > or =10 years); years of employment were lagged 10 years to account for latency. RESULTS: Compared to the national reference population mortality from cancer of stomach (observed 44, SMR = 117; 95% CI: 85-157) and lung (observed 154, SMR = 123; 95% CI: 104-144) was slightly increased. Using internal controls we observed excess deaths from stomach cancer in work area 1 (relative risk [RR] = 2.3; 95% CI: 1.2-4.2) and from lung cancer in work areas 1 (RR = 1.7; 95% CI: 1.2-2.3), 2 (RR = 1.5; 95% CI: 1.1-2.1), and 3 (RR = 1.3; 95% CI: 0.9-1.8). On the basis of cumulative years of employment an exposure response relationship was observed for mortality from both cancer sites among a subcategory of work area 1: weighing and mixing. Increased risks were also seen for lung cancer among workers employed in production of technical rubber goods. CONCLUSION: Our results support an association between an excess mortality from stomach and lung cancer and employment in early production stages of rubber manufacturing, especially weighing and mixing. This may point to an aetiologic role of asbestos or carbon black. For stomach cancer additional risk factors, e.g. exposure to dust and talc, deserve further investigation. The results of the present study do not support a causal role of nitrosamines for stomach or lung cancer.

Case-Control Studies↗
PubMed1999

Association of serum uric acid with all-cause and cardiovascular disease mortality and incident myocardial infarction in the MONICA Augsburg cohort. World Health Organization Monitoring Trends and Determinants in Cardiovascular Diseases.

Because previous findings have been inconsistent, we explored the association of serum concentrations of uric acid with all-cause and cardiovascular disease mortality and myocardial infarction prospectively. We used data from 1,044 men who are members of the World Health Organization Monitoring Trends and Determinants in Cardiovascular Diseases (MONICA) Augsburg cohort. The men, 45-64 years of age in 1984-1985, were followed through 1992. There were 90 deaths, 44 of which were related to cardiovascular disease; 60 men developed incident nonfatal or fatal myocardial infarction. We estimated hazard rate ratios from Cox proportional hazard models. Uric acid levels > or =373 micromol/liter (fourth quartile) vs < or =319 micromol/liter (first and second quartile) independently predicted all-cause mortality [hazard rate ratio = 2.8; 95% confidence interval (CI) = 1.6-5.0] after adjustment for alcohol, total cholesterol/high-density lipoprotein cholesterol ratio, hypertension, use of diuretic drugs, smoking, body mass index, and education. The adjusted risk of cardiovascular disease mortality was 2.2 (95% CI = 1.0-4.8), and that of myocardial infarction was 1.7 (95% CI = 0.8-3.3). Although residual confounding cannot be excluded, our results are among the few, in men, demonstrating a strong positive association of elevated serum uric acid with all-cause mortality. Future investigations may be able to evaluate whether uric acid contributes independently to the development of cardiovascular disease or is simply a component of the atherogenic metabolic condition known as the insulin resistance syndrome.

Cardiovascular Diseases↗
PubMed1999

An occupational cohort mortality study of women in the German rubber industry: 1976 to 1991.

Few previous studies of workers in the rubber industry have focused on women. We examined patterns of mortality among 2871 women employed in one of five German rubber plants for at least 1 year on or after January 1, 1976, and observed through December 31, 1991. All-causes mortality was near that expected (standardized mortality ratio [lsqbSMR], 101; 95% confidence interval [CI], 87 to 118), but cancer mortality was decreased (SMR, 90; 95% CI, 70 to 115). Nevertheless, excesses were observed for mortality from stomach cancer (SMR, 156; 95% CI, 63 to 322), lung cancer (SMR, 140; 95% CI, 56 to 289), and lymphatic system cancers (SMR, 175; 95% CI, 48 to 448). Stronger associations were observed among sub-cohorts defined by time period hired. Despite limited numbers of deaths, modest excesses of mortality due to specific cancers were observed and are consistent with previous studies.

Adult↗
PubMed1998

Epidemiological analyses of the relationship between environmental pollution and asthma.

Epidemiological studies performed on children and young adults indicate that the prevalence of asthma has increased over the past decades in a number of countries. Since genetic determinants alone are unlikely to explain these findings, environmental factors are expected to have an important impact on the prevalence of this disease. Environmental pollution, among many other factors, may play a role in the initiation and manifestation of asthma. However, there is little epidemiological evidence for a causal association between the classical major outdoor air pollutants, such as SO2 or particulate matter, and asthma. Evidence for an association between air pollution from motor vehicles and asthma is still controversial. Thus the indoor environment and other environmental determinants--including lifestyle factors--are likely to be more important as causes of asthma. Epidemiological studies are able to evaluate the effects of environmental factors on the health of human populations in their usual environments. In addition, they can measure associations between long-term environmental exposures and health outcomes. By using refined techniques for exposure and disease assessment, as well as time and cost-effective study designs, environmental epidemiology will increase the knowledge about the role of pollution as a possible cause of asthma.

Air Pollution↗
PubMed1998

Increasing prevalence of hay fever and atopy among children in Leipzig, East Germany.

BACKGROUND: Several surveys in children and adults have shown significantly lower prevalences of asthma and allergic diseases in eastern Europe than in western countries. In the former East Germany tremendous changes towards western lifestyle have occurred since unification. The aim of this survey was to investigate time trends in the prevalence of asthma and allergic diseases among children living in the eastern part of Germany. METHODS: In 1995-96, 2334 (87.5%) schoolchildren in Leipzig participated in a cross-sectional study that used the same methods as a previous survey done shortly after the fall of communism in 1991-92. A self-administered questionnaire was distributed to the parents. Children underwent cold-air challenge and allergy skinprick tests to six common aeroallergens. FINDINGS: The prevalence of hay fever (2.3% [34/1454] vs 5.1% [115/2252], p<0.0001) and atopic sensitisation (19.3% [252/1303] vs 26.7% [434/1624], p<0.0001) increased significantly between 1991-92 and 1995-96. However, there was no significant change in the prevalence of asthma, asthma-related symptoms, or bronchial hyper-responsiveness. INTERPRETATION: These findings suggest important differences in the development of atopic disorders. The children were born about 3 years before unification and were therefore exposed to western living conditions only after the third birthday. Thus, factors operating very early in life may be particularly important for the acquisition of childhood asthma, whereas the development of atopic sensitisation and hay fever may also be affected by environmental factors occurring beyond infancy.

Asthma↗