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H E Wichmann

Publications and source records attributed to H E Wichmann.

At least 91 records · Page 5Linked to original sources
PubMed2000

Daily mortality and fine and ultrafine particles in Erfurt, Germany part I: role of particle number and particle mass.

Increases in morbidity and mortality have been observed consistently and coherently in association with ambient air pollution. A number of studies on short-term effects have identified ambient particles as a major pollutant in urban air. This study, conducted in Erfurt, Germany, investigated the association of mortality not only with ambient particles but also with gaseous pollutants and indicators of sources. Part I of this study concentrates on particles. Data were collected prospectively over a 3.5-year period from September 1995 to December 1998. Death certificates were obtained from the local authorities and aggregated to daily time series of total counts and counts for subgroups. In addition to standard data for particle mass with diameters < or = 2.5 microm (PM2.5)* or < or = 10 microm (PM10) from impactors, a mobile aerosol spectrometer (MAS) was used to obtain size-specific number and mass concentration data in six size classes between 0.01 microm and 2.5 microm. Particles smaller than 0.1 microm were labeled ultrafine particles (three size classes), and particles between 0.1 and 2.5 microm were termed fine particles (three size classes). Concentrations of the gases sulfur dioxide (SO2), nitrogen dioxide (NO2), and carbon monoxide (CO) were also measured. The daily average total number concentration was 18,000 particles/cm3 with 88% of particles below 0.1 pm and 58% below 0.03 microm in diameter. The average mass concentration (PM2.5) was 26 microg/m3; of this, 75% of particles were between 0.1 and 0.5 microm in diameter. Other average concentrations were 38 microg/m3 for PM10, 17 microg/m3 for SO2, 36 microg/m3 for NO2, and 600 microg/m3 for CO. Ambient air pollution demonstrated a strong seasonality with maximum concentrations in winter. Across the study period, fine particle mass decreased, whereas ultrafine particle number was unchanged. The proportion of ultrafine particles below 0.03 microm diameter increased compared with the proportion of other particles. During the study, concentrations of SO2 and CO also decreased, whereas the concentration of NO2 remained unchanged. The data were analyzed using Poisson regression techniques with generalized additive modeling (GAM) to allow nonparametric adjustment for the confounders. Both the best single-day lag and the overall association of multiple days fitted by a polynomial distributed lag model were used to assess the lag structure between air pollution and death. Mortality increased in association with level of ambient air pollution after adjustment for season, influenza epidemics, day of week, and weather. In the sensitivity analyses, the results proved stable against changes of the confounder model. We saw comparable associations for ultrafine and fine particles in a distributed lag model where the contribution of the previous 4 to 5 days was considered. Furthermore, the data suggest a somewhat more delayed association of ultrafine particles than of fine particles if single-day lags are considered. The associations tended to be stronger in winter than in summer and at ages below 70 years compared to ages above 70 years. Analysis of the prevalent diseases mentioned on death certificates revealed that the overall association for respiratory diseases was slightly stronger than for cardiovascular diseases. In two-pollutant models, associations of ultrafine and fine particles seemed to be largely independent of each other, and the risk was enhanced if both were considered at the same time. Furthermore, when the associations were summed for the six size classes between 0.01 and 2.5 microm, the overall association was clearly stronger than the associations of the individual size classes alone. Associations were observed for SO2, NO2, and CO with mortality despite low concentrations of these gases. These associations disappeared in two-pollutant models for NO2 and CO, but they remained stable for SO2. The persistence of the SO2 effect was interpreted as artifact, however, because the SO2 concentration was much below levels at which effects are usually expected. Furthermore, the results for SO2 were inconsistent with those from earlier studies conducted in Erfurt. We conclude that both fine particles (represented by particle mass) and ultrafine particles (represented by particle number) showed independent effects on mortality at ambient concentrations. Comparable associations for gaseous pollutants were interpreted as artifacts of collinearity with particles from the same sources.

Adolescent↗
PubMed1999

Increases in heart rate during an air pollution episode.

This paper assesses whether air pollution increases resting heart rates in 2,681 men and women aged 25-64 years who participated in the MONICA (monitoring of trends and determinants in cardiovascular disease) Augsburg cohort. Increases in heart rate were observed during the air pollution episode in January 1985 compared with non-episode days adjusted for cardiovascular risk factors and meteorologic parameters. Consistently, heart rates were also elevated at high concentrations of sulfur dioxide, total suspended particulates, or carbon monoxide. Acceleration in heart rates indicates an altered autonomic control of the heart in association with air pollution, which may contribute to the observed health effects in association with air pollution.

Adult↗
PubMed1999

A genome-wide search for linkage to asthma. German Asthma Genetics Group.

Asthma is among the most frequent chronic diseases in childhood. Although numerous environmental risk factors have already been identified, the basis for familial occurrence of asthma remains unclear. Previous genome screens for atopy in British/Australian families and for asthma in different American populations showed inconsistent results. We report a sib pair study of a sample of 97 families, including 415 persons and 156 sib pairs. Following an extensive clinical evaluation, all participants were genotyped for 351 polymorphic dinucleotide markers. Linkage analysis for asthma identified four chromosomal regions that could to be linked to asthma: chromosome 2 (at marker D2S2298, P = 0.007), chromosome 6 (around D6S291, lowest P = 0.008), chromosome 9 (proximal to D9S1784, P = 0.007), and chromosome 12 (D12S351, P = 0.010). These linkage regions could be reproduced for all loci by analysis of total or specific immunoglobulin E (minimum P values at these regions were 0. 003, 0.001, 0.010, and 0.015, respectively).

Asthma↗
PubMed1999

Trends in allergies among children in a region of former East Germany between 1992-1993 and 1995-1996.

A lower prevalence of asthma and allergies has been reported among children and adults living in the area of former East Germany compared with those living in West Germany. After German reunification in 1990, the East German population rapidly adopted a western lifestyle. Therefore, this study examined if the prevalence rates of allergic diseases, symptoms, and sensitisation and asthma have increased among East German children since German reunification. - Children aged 5 to 7 years living in the region of Sachsen-Anhalt, East Germany were examined in two cross-sectional studies during 1992-93 (n = 769, response rate 84.0%) and 1995-96 (n = 725, response rate 74.6%). Sensitisation was assessed by specific immunoglobulin E measurements against five common aeroallergens using the CAP-FEIA technique. After adjustment for sex, parental education, season of examination, day care attendance, breast feeding, environmental tobacco smoke exposure, cat dander exposure, and several indoor factors, an increase in the prevalence of self-reported, physician-diagnosed allergies (OR 1.44, 95% CI 1.01-2. 06), but not in allergic sensitisation (OR 0.85, 95% CI 0.62-1.16) was found. The only evidence of an increase in allergies of the self-reported increase in the prevalence of physician-diagnosed allergies is likely due to changes in physician diagnostic patterns and the heightened public awareness of allergic diseases. - In conclusion, there were no significant changes in the prevalence of asthma, allergic rhinitis, or self-reported symptoms of allergic diseases.

Adult↗
PubMed1999

Age of entry to day nursery and allergy in later childhood.

BACKGROUND: Infections in early childhood may prevent allergies in later life. If this hypothesis is true, early exposure to childcare outside the home would protect against atopy by promotion of cross infections. We investigated whether children who attend a nursery at a young age have a lower rate of atopy and fewer allergies than children who attend from an older age. METHODS: In a cross-sectional study carried out in 1992-93, we examined 2471 children in three age-groups (5-7, 8-10, and 11-14 years) from the towns of Bitterfeld, Hettstedt, and Zerbst in eastern Germany. The children's parents answered a questionnaire about allergies and symptoms, attendance at day care, and related factors. Sensitisation was assessed by skin-prick tests and measurement of allergen-specific IgE antibodies in serum. FINDINGS: In 669 children from small families (up to three people), the prevalence of atopy was higher among children who started to attend day nursery at an older age than in those who started to attend at a younger age (p<0.05). Compared with children who first attended at age 6-11 months, the adjusted odds ratios for a positive skin-prick test were 1.99 (95% CI 1.08-3.66) for children who attended at age 12-23 months and 2.72 (1.37-5.40) for those who attended at age 24 months and older. In 1761 children from large families (more than three people), age of entry to day nursery had no effect on atopy. INTERPRETATION: Our findings accord with the hypothesis that early infection may protect against allergies in later life.

Adolescent↗
PubMed1999

Occupational risk factors for lung cancer in women: results of a case-control study in Germany.

BACKGROUND: To investigate the association between lung cancer and occupational factors in women. METHODS: Six hundred eighty-six women with lung cancer and 712 controls matched for age and region were interviewed to gather occupational histories and information about other risk factors and confounders. Odds ratios (OR) and 95%-confidence intervals (CI) were calculated. RESULTS: There were 11 cases and 2 controls who reported occupational asbestos exposure. Significantly elevated risks (P < 0.05, smoking-adjusted), were observed in the following industries: chemical, oil (OR 3.7), pottery, glass (OR 2.5), engine, vehicle building (OR 2.2), paper, wood, print (OR 1.9), cleaning service, hairdressing, housekeeping, waste disposal (OR 1.5); and occupations: assemblers, unskilled metal workers (OR 2.5), stock clerks, etc. (OR 1.6), restaurant owners and hoteliers (OR 2.7), as well as waitresses and travel attendants (OR 2.6). CONCLUSIONS: The study provides evidence that both occupations previously observed as hazardous in males, and occupations of particular significance for women only, play a role in the risk of lung cancer in women.

Adult↗
PubMed1999

Lung cancer risk in male workers occupationally exposed to diesel motor emissions in Germany.

BACKGROUND: Although in several epidemiological studies exposure to diesel motor emissions (DME) shows an elevated lung cancer risk, it is still controversial whether DME is a human carcinogen. METHODS: In a pooled analysis of two case-control studies on lung cancer in Germany a total of 3498 male cases with histologically or cytologically ascertained lung cancer and 3541 male population controls were included. Information about lifelong occupational and smoking history was obtained by questionnaire. Drivers of lorries, buses, taxies, diesel locomotives and forklift trucks, bulldozers, graders, excavators, and tractors, were considered as exposed to DME and their cumulative exposure was estimated. All odds ratios were adjusted for smoking and asbestos exposure. RESULTS: The evaluation of lung cancer risk for all jobs with DME-exposure combined showed an odds ratio of OR=1.43 (95%-CI: 1.23-1.67). Most pronounced was the increase in lung cancer risk in heavy equipment operators (OR=2. 31 95%-CI: 1.44-3.70). The risk of tractor drivers increased with length of employment and reached statistical significance for exposures longer than 30 years (OR=6.81, 95%-CI: 1.17-39.51). The group of professional drivers (e.g., trucks, buses, and taxies), showed an increased risk only in West Germany (OR=1.44, 95%-CI: 1. 18-1.76), but not in East Germany (OR=0.83, 95%-CI: 0.60-1.14). DME-exposure in other traffic related jobs (e.g., diesel engine locomotive drivers, switchmen, forklift operators) was associated with an odds ratio of OR=1.53 (95%-CI: 1.04-2.24). CONCLUSIONS: The study provides further evidence that occupational exposure to diesel motor emissions is associated with an increased lung cancer risk.

Aged↗
PubMed1999

Indoor risk factors for atopic eczema in school children from East Germany.

This study aimed to investigate the relation between environmental influences such as arsenic, cadmium, lead, and mercury, as well as environmental tobacco smoke, pet keeping, and heating systems on the prevalence of atopic eczema. Therefore, a multicenter cross-sectional study of school children aged 5-14 years, including a standardized questionnaire, blood and urine analyses, and a dermatological examination, was undertaken. A cases-control approach was chosen in order to identify relevant risk factors. A total of 2200 school children (response 79.1%) of two areas (Bitterfeld, Hettstedt) polluted by industrial activities and an agricultural control region (Zerbst) of the former German Democratic Republic were examined. Atopic eczema as identified by dermatological examination and history was the outcome variable of interest. Body burden of arsenic and heavy metals and questionnaire data on environmental tobacco smoke exposure, pet keeping, and heating system were investigated as potential risk factors. The overall prevalence of atopic eczema was 2.6%, with higher prevalences in the industrial areas (2.5 and 2.9%) compared to the control area (1.6%, not significant). Bivariate analyses did not reveal statistically significant associations between atopic eczema and tobacco smoke exposure or the body burden of arsenic and heavy metals. According to multiple logistic regression analysis, atopic eczema was significantly more frequent in predisposed families and those who reported keeping guinea pigs (OR=4.37, CI 2.15-8.91), but not other pets, like dogs, cats, and hamsters. In comparison to a distant heating system, a decreased risk was observed in households with central heating system (OR=0.30, CI 0.10-0.90), whereas the presence of a gas heater with an exhaust pipe connection to the wall was associated with a significantly elevated risk for eczema (OR=8.22, CI 2.44-27.66). The heating system and exposure to certain animal allergens are related to the manifestation of atopic eczema. Further studies are needed to clarify how far a causal relationship is reflected by these findings.

Adolescent↗
PubMed1999

Association between severity of atopic eczema and degree of sensitization to aeroallergens in schoolchildren.

BACKGROUND: A subgroup of patients with atopic eczema exhibits aggravation through contact with aeroallergens. Little is known from population-based studies, however, about the association between the severity of eczematous skin disease and the degree of aeroallergen sensitization. OBJECTIVE: We sought to investigate the relationship between IgE-mediated allergic sensitization to aeroallergens and severity of atopic eczema in schoolchildren. METHODS: A nested case-control analysis on atopic eczema was performed on the basis of a cross-sectional study of 2201 East German schoolchildren aged 5 to 14 years. Atopic eczema and its severity was identified by dermatologic examination. Total and allergen-specific IgE antibodies to grass and birch pollen, Cladosporium herbarum, Dermatophagoides pteronyssinus, and cat epithelium in serum were determined, and additional information was obtained by means of standardized questionnaire. RESULTS: The overall prevalence of actual atopic eczema was 2.5%. Thirty-seven percent of the children were sensitized to at least one allergen. Children with atopic eczema were significantly more often sensitized than those without skin disease (75.0% vs 36.3%; odds ratio, 5.27; 95% confidence interval, 2.54-11.15). This was observed for each single allergen. The prevalence of atopic eczema increased significantly with increasing RAST class (chi(2) trend test for each allergen, P <.0001). Also, the prevalence of sensitization increased with the severity of the disease (chi(2) trend test for each allergen, P <.0001). This association was pronounced for house dust mite and cat allergen. Multiple linear regression analyses showed significant associations between the severity score of atopic eczema and concentrations of allergen-specific IgE to dust mite (P =.032) and cat (P =.014) allergens after adjustment for sex, age, location, and parental predisposition. CONCLUSIONS: The degree of sensitization is directly associated with the severity of atopic eczema. We speculate that early epicutaneous sensitization to aeroallergens may be enhanced by damage of the skin barrier function. The specific IgE response seems to contribute to the severity of the disease in a dose-dependent fashion.

Adolescent↗
PubMed1999

How many myeloid post-progenitor cells have to be transplanted to completely abrogate neutropenia after peripheral blood progenitor cell transplantation? Results of a computer simulation.

Although hematopoietic recovery following high-dose chemotherapy (HD-CT) and peripheral blood progenitor cell (PBPC) transplantation is rapid, there is still a 5- to 7-day period of severe neutropenia which, theoretically, might be abrogated by an additional transplantation of more differentiated myeloid post-progenitor cells (MPPC). However, both the number of MPPC required to abrogate neutropenia as well as the optimum scheduling of MPPC infusions are currently unknown. Therefore, these questions were addressed by applying a computer model of human granulopoiesis. First, model calculations simulating varying levels of chemotherapy dose intensity were performed and compared with typical clinical neutrophil recovery curves. Using this approach, the data for HD-CT without PBPC transplantation could be reproduced by assuming a reduction of stem cells, committed granulopoietic progenitors and proliferating precursors to about 0.001% of normal. PBPC-supported HD-CT was reproduced by increasing the starting values to at least 0.1%, which corresponded to about 1 to 2 x 10(5)/kg transplanted CFU-GM. Interestingly, reproduction of PBPC-supported HD-CT data could be observed for a wide range of starting values (0.1%-10% of normal), thus confirming the clinical observation that hematopoietic recovery after PBPCT cannot be improved by increasing the dose of transplanted cells over a certain threshold. Using the same simulation model, we then studied the effects of an additional MPPC transplantation. The results showed, that at least 5.7 X 10(8) MPPC/kg have to be provided in addition to the normal PBPC graft to avoid neutropenia <100/microL, and that MPPC are best transplanted on days 0 and 6 after HD-CT. Assuming a 100- to 120-fold cellular ex-vivo expansion rate and MPPC representing about 70% of total expanded cells, 5.7 X 10(8) MPPC/kg could be generated starting from 1 to 2 leukapheresis preparations with about 7 to 8 x 10(6) CD34+ PBPC/kg. Considering furthermore, that only a fraction of ex-vivo generated cells will seed and effectively produce neutrophils in-vivo, the required number of MPPC is most likely even higher and, therefore, might be difficult to be achieved clinically. However, the validity of the model results remains to be proven in appropriate clinical studies.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Allergens in house-dust samples in Germany: results of an East-West German comparison.

The background of this study is the finding of several studies that the frequency of respiratory allergies was significantly higher in the former West Germany than the former East Germany. The present study investigated the levels of allergens of house-dust mite (Der p 1 and Der f 1), cat (Fel d 1), and cockroach (Bla g 2) in the household dust of 201 homes in Hamburg (West Germany) and 204 homes in Erfurt (East Germany), and examined the factors that affect these levels. The characteristics of homes were assessed by a questionnaire. The allergen levels were studied in dust from living rooms (LR), bedrooms (BR), and mattresses (MA). We detected in samples from Hamburg significantly higher allergen concentrations than in Erfurt: three times higher Der p 1, five times higher Der f 1, and three times higher Fel d 1. For Bla g 2, no comparison was possible because the concentrations were below the detection limit in 93% of the samples. Most of the differences could be explained by differences in housing and living characteristics between both cities. The mean ratio of Der p 1 levels in mattress dust between Hamburg and Erfurt decreased from 4.1 to 1.54 (NS) after adjustment for season, building material, age of the house, story of the dwelling, type of heating, age of carpet/mattress, presence of dogs, and indoor climate (temperature, humidity). The mean ratio of Der f 1 levels decreased from 6.9 to 2.78 (P<0.05) after adjustment for these factors. The mean ratio for Fel d 1 in mattress dust decreased fom 4.03 to 1.65 (P<0.05) after adjustment for season, building material, story of dwelling, size of dwelling, ventilation, cleaning routines, and pets. A similar reduction was seen for floor dust (LR plus BR). Our results indicate that the differences between the concentrations of mite and cat allergens found in Hamburg and Erfurt are explicable mainly, but not completely, by different building characteristics (age of houses, building material, story, and size of the dwelling) which affected the indoor climate, as well as by differences in other individual living habits (keeping of pets, age of carpets or mattresses, and cleaning routines).

Air Pollution, Indoor↗
PubMed1999

Occupational risk factors for lung cancer among young men.

OBJECTIVES: This study evaluated whether occupational exposure plays a role for lung cancer at a very young age. METHODS: In a pooled analysis of 2 German case-referent studies including 3498 incident cases among men and 3541 male population referents, a group of men (187 cases and 202 referents) aged > or =45 years was compared with a group of 2186 cases and 2146 referents aged 55-69 years. Occupational exposure to known (A list) or suspected (B list) lung carcinogens was assessed using job and industry codes, and exposure to asbestos was assessed using job-specific supplementary questionnaires. A conditional logistic regression was used to calculate the odds ratios (OR) and to control for smoking. RESULTS: Asbestos exposure showed an odds ratio (OR) of 2.39 [95% confidence interval (95% CI) 1.41-4.04] for the younger group and 1.46 (95% CI 1.24-1.72) for the older group. Having ever worked in a job belonging to the A list as compared with never working in an A- or B-list job was associated with a significantly increased risk for the younger (OR 2.06, 95% CI 1.03-4.12) and older (OR 1.35, 95% CI 1.10-1.65) groups, adjusted for asbestos. Lung cancer risk for those working in A-list jobs at a very young age (under 16 years) was increased in the younger group (OR 6.14, 95% CI 1.41-28.01) in contrast to the older group (OR 1.19, 95% CI 0.91-1.63). CONCLUSION: Occupational risk factors play an important role for lung cancer among young men. Early age at first exposure may favor an early age of the onset of lung cancer.

Adult↗
PubMed1999

The German uranium miners cohort study: feasibility and first results.

In Germany, the largest single cohort study on uranium miners to date is being conducted. The cohort includes about 64,000 workers of the former Wismut company in eastern Germany. Inclusion criteria were: a date of employment between 1946 and 1989, a minimum period of employment of 180 days, and complete information on working history. Due to poor working conditions in the late 1940s and early 1950s, miners were exposed to high levels of radiation, while later radiation exposure was significantly reduced. The aim of the cohort study is to evaluate the risk of lung cancer and other cancers associated with several indicators of exposure to radon and its progeny, with particular attention to low levels of radiation. Radon exposure will be estimated by a detailed job- exposure matrix. Some information about smoking, dust and arsenic is already available. About 49,000 miners are defined as exposed (underground or processing), while the internal control group (surface only) consists of 15,000 workers. A total of 1,436 lung cancer deaths among cohort members have been reported. The first mortality follow-up will be finished early in 2002, and a total of about 3,000 lung cancer deaths are expected by then.

Adult↗
PubMed1999

Recommendations for the monitoring of short-term health effects of air pollution: lessons from the APHEA Multi Centre European Study.

Accumulating evidence from European cities indicates that current levels of ambient air pollution are likely to be associated with detectable effects on daily mortality and hospital admissions. Public health authorities everywhere are concerned about the possible effects of air pollution on the health of their populations but there are no guidelines for how these effects can efficiently be monitored. Furthermore, decisions about air pollution monitoring tend to be made without reference to the epidemiological requirements of health monitoring. The APHEA project (Air Pollution and Health a European Approach) investigated the short-term health effects of air pollution in 15 European cities. Experience gained in this project provides a basis for recommendations to public health and environmental authorities concerning the requirements for a basic health monitoring system. This paper considers the theoretical and practical aspects of a monitoring system and makes recommendations concerning 1) the minimum data set required, 2) the methods of statistical analysis and presentation and 3) Europe-wide coordination of monitoring.

Air Pollution↗
PubMed1998

Multicenter case-control study of exposure to environmental tobacco smoke and lung cancer in Europe.

BACKGROUND: An association between exposure to environmental tobacco smoke (ETS) and lung cancer risk has been suggested. To evaluate this possible association better, researchers need more precise estimates of risk, the relative contribution of different sources of ETS, and the effect of ETS exposure on different histologic types of lung cancer. To address these issues, we have conducted a case-control study of lung cancer and exposure to ETS in 12 centers from seven European countries. METHODS: A total of 650 patients with lung cancer and 1542 control subjects up to 74 years of age were interviewed about exposure to ETS. Neither case subjects nor control subjects had smoked more than 400 cigarettes in their lifetime. RESULTS: ETS exposure during childhood was not associated with an increased risk of lung cancer (odds ratio [OR] for ever exposure = 0.78; 95% confidence interval [CI] = 0.64-0.96). The OR for ever exposure to spousal ETS was 1.16 (95% CI = 0.93-1.44). No clear dose-response relationship could be demonstrated for cumulative spousal ETS exposure. The OR for ever exposure to workplace ETS was 1.17 (95% CI = 0.94-1.45), with possible evidence of increasing risk for increasing duration of exposure. No increase in risk was detected in subjects whose exposure to spousal or workplace ETS ended more than 15 years earlier. Ever exposure to ETS from other sources was not associated with lung cancer risk. Risks from combined exposure to spousal and workplace ETS were higher for squamous cell carcinoma and small-cell carcinoma than for adenocarcinoma, but the differences were not statistically significant. CONCLUSIONS: Our results indicate no association between childhood exposure to ETS and lung cancer risk. We did find weak evidence of a dose-response relationship between risk of lung cancer and exposure to spousal and workplace ETS. There was no detectable risk after cessation of exposure.

Aged↗