on behalf of the LISA study group Allergens and endotoxin on mothers9 mattresses and total immunoglobulin E in cord blood of neonates. J. Heinrich, G. Bolte, B.Hölscher, J. Douwes, I. Lehmann, B. Fahlbusch, W. Bischof, M. Weiss, M. Borte, H-E. Wichmann, on behalf of the LISA study group. #ERS Journals Ltd 2002. ABSTRACT: The current authors examined whether mite and cat allergen and bacterial endotoxin levels in dust of the mothers9 mattresses were associated with cord blood immunoglobulin (Ig)E (CB-IgE) levels in newborns.Data from 1,332 term and normal weight neonates, from an ongoing birth cohort study, Influences of life-style related factors on the immune system and the development of allergies in childhood (LISA), with complete information on exposure to biocontaminants in mattress dust and CB-IgE were analysed. (4th quartile) were chosen as cut-offs. Nonparametric smoothing (generalised additive models) showed statistically significant confounder-adjusted associations between elevated CB-IgE levels (o0.45 kU?L -1 ) and log-transformed exposures to cat (linear), mite (inverse u-shaped), and endotoxin (u-shaped).After adjustment for covariables, elevated CB-IgE levels (logistic regression using the 1st-4th quartiles of exposure) were positively associated with high cat-allergen exposure and medium exposure to mite allergen, but were inversely associated with exposure to endotoxin. The associations were similar, but somewhat weaker, when 0.35 kU?L -1 was used as cut-off. These results, showing an association between prenatal allergen and endotoxin exposures and immunoglobulin E production, suggest that the development of foetal immune responses may be affected.

Measurements of biocontaminants in settled house dust once a year are commonly used to assess long-term exposure. To examine stability over time and seasonal variation, we measured concentrations of mite and cat allergens, endotoxin and mold spores in living room floor dust in 745 German homes collected twice a year in two different seasons. The study population consisted of adults and children living in five different areas in Germany. All dust samples were collected in a standardized manner from the living room floor and taken during the years 1995 to 1998. The median interval between the two dust samplings was approximately 7 months. Mite and cat allergens were measured in settled house dust by monoclonal antibodies, endotoxin by the limulus amebocyte lysate method, and total spore counts by cultural methods. Crude Pearson's correlation coefficients between logtransformed concentrations in the first and second dust samples ranged between 0.65 and 0.75 for allergens, 0.59 for endotoxin and only 0.06 for total spore counts. The strongest and most consistent seasonal effects were observed for fungi with highest levels in July-September. Cat allergen concentrations were found consistently to be increased in January-March. Mite allergens did not show a strong and consistent seasonal pattern. We conclude that repeated measurements of mite and cat allergens and endotoxin in settled house dust improve the estimate for annual mean concentrations. However, even a single observation of these biocontaminants may be a good proxy for a 1-year exposure since repeated measures were highly correlated. However, repeated measurements of fungi levels were only weakly correlated and thus repeated observations for assessment of annual means of total spore counts are needed.

Currently, there is ongoing discussion regarding potential protective effects of exposure to pets during early childhood on the development of atopic disorders in children later in life. We used data from three consecutive cross-sectional surveys to study the relationship between contact with dogs, cats and other pets, and allergic diseases in schoolchildren 5-14 years of age. In three study areas of the former East Germany, 7,611 questionnaires were received from 5,360 different children who were examined between 1992 and 1999 as school entrants, or third- or sixth-graders. Allergic sensitization to common aeroallergens (birch, grass, mite, cat) was assessed by specific serum immunoglobulin E (IgE) concentrations [using radioallergosorbent testing (RAST)] for 85% of the children. After adjustment for possible confounders, inverse associations were found between contact with dogs in the first year of life and lifetime prevalences of asthma [odds ratio (OR) = 0.68; 95% confidence interval (CI): 0.43-1.08], hay fever (OR = 0.61; 95% CI: 0.39-0.95), eczema (OR = 0.76; 95% CI: 0.61-0.94), itchy rash (OR = 0.76; 95% CI: 0.61-0.94), and pollen sensitization (RAST >/= 4: OR = 0.56; 95% CI: 0.38-0.82). These effects were more pronounced for children with atopic parents. Similar associations were observed for current contact with dogs. We identified no clear relationships for the other pets (cats, rodents, birds), with the exception that children currently exposed to cats were more likely to be sensitized against cats. In conclusion, this study supports the hypothesis of a potential protective mechanism related to dog exposure in early life, especially for children of atopic parents. However, this association was found only for dogs and not for cats.

It has been postulated that the prevalence of atopic diseases and their increase over time are associated with regional differences in diet and trends. The results of an ecological correlation study comparing the mean daily intake of selected dietary constituents and the prevalence of allergic sensitization in adults in Europe is presented.Prevalence data from the European Community Respiratory Health Survey (ECRHS) were used. For eight out of 37 ECRHS centres (including 3,872 subjects), comparable dietary data could be obtained. The effect for each dietary constituent was modelled using logistic regression analyses with a term for over dispersion.Inverse associations between the prevalence of allergic sensitization and the energy adjusted intake of fruit were found (odds ratio (OR)~0.68, p~0.034). Furthermore OR for energy adjusted intake of vitamin A (OR~0.73, p~0.057), vitamin C (OR~0.83, p~0.338) and riboflavin (OR~0.72, p~0.077) were consistently v1, but confidence intervals were wider. Daily intake of monounsaturated fatty acids (energy adjusted) was positively associated with sensitization prevalence (OR~1.59, p~0.035).These results support the hypothesis that a high intake of monounsaturated fatty acids might promote the development of allergic sensitization.

In 1998, the German Environmental Survey (GerES III) recruited approximately 5000 adults between the ages of 18 and 69 years. The study population for these analyses consisted of 1580 smokers (34% of the total population) and 3126 nonsmokers. Nicotine and cotinine concentrations in urine were determined by HPLC methods with UV-detection and corrected for creatinine. Nicotine and cotinine concentrations differed between smokers and nonsmokers by factors of 10-100. The multiple linear regression models used for the analyses of nicotine detection in the urine of smokers explained 43.2% and 42.3% of the total volume-specific and creatinine-specific variances, respectively. Cigarette smoking was the major factor responsible for 41% of the total variance. The explained variances of the cotinine results were larger, 51.0% and 49.3% of the total variance were volume-specific and creatinine-specific, respectively. More than 20% of nonsmokers in GerES III were exposed to environmental tobacco smoke at home, at work or in other places. The logistic regression analysis approach used for the group of nonsmokers showed the greatest effects for those exposed to tobacco smoke at home (adjusted OR varied between 4 and 6). These results were seen for nicotine as well as for cotinine excretion. Exposure to tobacco smoke in the workplace doubled the risk for the detection of nicotine and cotinine in urine. When other risk factors such as age, sex, social status, community size, season of urine collection, and the consumption of food containing nicotine such as potatoes, cabbage, tea were included, the effect estimates for tobacco smoke exposure remained unchanged. A new federal bill to diminish environmental tobacco smoke (ETS) exposure in the workplace was recently passed in Germany, but protection of nonsmokers from smoking family members at home needs more attention.