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Notes: Background and objective The increasing urbanization and the decrease in the numbers of farms in southern Germany might be associated with an increasing prevalence of allergic diseases. We compared the prevalence of allergic diseases in farmers, and rural, suburban and urban residents in the small geographical area of Augsburg in southern Germany.Methods In a cross-sectional survey adults, aged 25–75 years selected from the community population register were investigated. Rural, suburban and urban residents were defined by community size and farmers by occupation. Allergic respiratory disorders were assessed by self-administered questionnaires and specific IgE antibodies to five common aeroallergens.Results In comparison to rural residents the urban population had an increased risk of allergic rhinitis (OR = 1.5; 95% CI: 1.2–1.9), atopic sensitization (OR = 1.2; 95% CI: 1.0–1.4) and sensitization against pollen (OR = 1.5; 95% CI: 1.2–1.9). There was no difference in the risk of asthma (OR = 1.0; 95% CI: 0.6–1.6) and a decreased risk in the sensitization against house dust mite (OR = 0.8; 95% CI: 0.7–1.0). The suburban residents did not differ from urban residents. Farmers had lower risks in allergic rhinitis, atopic sensitization, sensitization against pollen and mites (OR = 0.63; 0.86; 0.51 and 0.80, respectively) than rural non-farming residents, however, these differences were statistically not significant. Reported allergic rhinitis with sensitization to pollen was 2.5 times (95% CI: 1.8–3.6) more prevalent in urban than in rural residents.Conclusion A farming environment and rural lifestyle might be associated with unknown protective factors impacting the prevalence of allergies.

Notes: Background:  Worm infestations may play a role in preventing allergies. There is a lack of epidemiological information from Western countries on the association between worm infestation and eczema.Objective:  To investigate the association between worm infestation and eczema in a proper temporal sequence and under consideration of allergic sensitization.Methods:  Two surveys were performed in East German school children. Questionnaire data included the history of eczema and worm infestation and their time of onset. Specific IgE antibodies to five common aeroallergens were measured and used to define nonatopic and atopic eczema. Logistic regression analyses were performed to control for relevant confounders (age, sex, parental school education and history of allergies). In order to confirm the findings a corresponding conditional regression analysis was applied on cases and controls matched by age and sex.Results:  A total of 4169 children participated (response 75 and 76%) who were, on average, 9.2 years old (47% girls). Overall 17.0% reported a prior worm infestation (Ascaris 44%, Oxyuris 33%) and 18.1% had a history of eczema. Eczema occurred significantly less frequent in children who had a worm infestation (prior to the onset of eczema) compared with children without such a history (8.1%vs 16.5%, ORadj: 0.45, 95% CI: 0.33–0.60). The finding was confirmed by the corresponding matched case–control analysis (ORadj: 0.57, 95% CI: 0.41–0.79). Atopic eczema was affected more by a prior worm infestation (ORadj: 0.31, 95% CI: 0.18–0.56) than the nonatopic eczema (ORadj: 0.58, 95% CI: 0.40–0.84). A total of 29.1% exhibited specific IgE antibodies to at least one aeroallergen. Sensitized children gave significantly less frequent a history of worm infestation (14.2%vs 18.3%, ORadj: 0.74, 95% CI: 0.60–0.92). Stratified analysis revealed that this effect most pronounced for a sensitization to house dust mite.Conclusions:  A worm infestation is associated with a reduced frequency of subsequent eczema, especially the atopic type. Furthermore allergic sensitization, especially to house dust mite, and worm infestation are negatively associated. The data support the concept that a lack of immune-stimulation by parasitic infections contributes to the development of allergies.

Notes: Background:  Moisture is vitally important for house dust mites and they cannot survive in cold or hot-dry climates.Aims of the study:  To investigate the influence of two extraordinarily cold and dry winters in 1995/1996 and 1996/1997 on house dust mite levels in German homes.Methods:  Dust samples were collected between June 1995 and December 2001 on the mattresses of 655 adults and 454 schoolchildren living in five different areas of Germany. We compared house dust mite allergen Dermatophagoides pteronyssinus (Der p 1) levels before and during the winters of 1995/1996 and 1996/1997 with levels after these winters.Results:  D. pteronyssinus (Der p 1) levels in samples taken after the cold winters of 1995/1996 and 1996/1997 were approximately two times lower than Der p 1 levels in dust samples collected before or during these respective winters (Geometric means: Erfurt 89 vs 33 ng/g; Hamburg 333 vs 219 ng/g; Bitterfeld, Hettstedt, and Zerbst 296 vs 180 ng/g). Except for Hamburg, the decrease in Der p 1 levels was statistically significant. D. pteronyssinus levels measured in dust samples collected in 2001 (i.e. 3 years after the two cold winters) show a statistically non-significant increase (Geometric means: Erfurt 33 vs 39 ng/g; Hamburg 219 vs 317 ng/g), suggesting that it may take a long time for mite allergen levels to increase again after a sudden decrease.Conclusion:  We conclude that Der p 1 levels in German mattress dust samples have been approximately reduced by a factor of three to four by the two consecutive cold winters of 1995/1996 and 1996/1997.

Notes: Background:  It has been suggested that exposure to elevated levels of endotoxin decreases the risk of allergic sensitization.Objective:  To examine the associations between current exposure to bacterial endotoxin in house dust and allergic sensitization in adults.Methods:  In 1995–1996, we conducted a nested case–control study following a cross-sectional study performed within the European Community Respiratory Health Survey (ECRHS). Data of 350 adults aged 25–50 years was analysed. Allergic sensitization was assessed by measurement of specific immunoglobulin E (IgE) against several inhalant allergens. Living room floor dust samples were taken. The endotoxin content was quantified using a chromogenic kinetic Limulus amoebocyte lysate test.Results:  Multiple logistic regression analysis showed a negative association between exposure to house dust endotoxin and severe allergic sensitization. Odds ratios (95% CI) adjusted for place of residence, gender, age, and ‘caseness’ were 0.80 (0.64–1.00) for sensitization to ≥1 allergen and 0.72 (0.56, 0.92) for sensitization to ≥2 allergens using 3.5 kU/l as a cut-off value for sensitization. With regard to single allergens, the protective effect of endotoxin was strongest for pollen sensitization [aOR (95% CI) = 0.74 (0.58, 0.93)].Conclusion:  Our results indicate that current exposure to higher levels of house dust endotoxin might be associated with a decreased odds of allergic sensitization in adults.

Notes: Background:  There is evidence that the use of alternative medicine (AM) for allergies has increased. However, little is known from population-based studies about what determines its use. The objective of this study was to evaluate the patterns of use of AM for allergies. Methods:  A population-based nested case-control study was conducted in 2000–01 using computer-assisted telephone interviews. Three hundred and fifty-one adults participated (median age 46 years) with allergies including hay fever, asthma, atopic eczema, and food hypersensitivity. Information was obtained on demographics, prevalence, motivation, information, type of AM, provider, costs, willingness to pay, and subjective assessment of AM. Results:  26.5% of participants used AM because of their allergies. Compared to nonusers, this group of users was significantly younger (median age 43 vs 47; p =0.004) and better educated (school education 〉 8 year vs ≤ 8 year; odds ratio (OR) 2.17, 1.28–3.67) and was mostly motivated by the assumption of few side-effects (78.3%), by a wish to try everything (71.7%), and by unsatisfying results from conventional therapy (66.3%). Users also had more experience with conventional therapy than nonusers (94.6% vs 63.6%; OR 10.10, 4.00–25.72). Four procedures accounted for almost the entire usage: homeopathy (35.3%), autologous blood injection (28.1%), acupuncture (16.6%), and bioresonance (10.0%). The AM were mostly promoted (40.2%) and provided (60.9%) by medical doctors, and produced median costs for single and entire treatment of 4 € (15–205) and 205 € (15–1278)e. Reimbursement from insurance companies was received by 52.3%, in full (37.8%) or partial (14.5%). Most subjects (55.4%) admitted that they would pay more (median 153e) for the achieved result. Users scored the efficacy of conventional therapy significantly lower ( p 〈0.001) than nonusers, and assessed the results of AM as very good (28.6%) or rather good (53.8%). Conclusions:  AM is used widely for allergies by the general population and is associated with considerable costs. This has implications for the health care system and health policy.

Notes: Background: We aimed to determine the prevalence of contact sensitization in the general population and to investigate associations with important sociodemographic and medical characteristics. Methods: Within a population-based nested, case-control study in Germany, we performed patch tests with 25 standard allergens in 1141 adults (50.4% female, age median 50 years). Additional information was obtained by a dermatologic examination, a standardized interview, and blood analysis. Results: At least one positive reaction was exhibited by 40.0% of the subjects, with reactions most frequently observed to fragrance mix (15.9%), nickel (13.1%), thimerosal (4.7%), and balsam of Peru (3.8%). Women were sensitized more often than men (50.2%vs 29.9%, OR 2.36, CI 1.84–3.03), and this was also significant for fragrance mix, nickel, turpentine, cobalt chloride, and thimerosal. Contact sensitization was more frequent in subjects who reported adverse skin reactions (53.8% vs. 32.6%; OR 2.41, CI 1.85–3.14), and this was particularly true for sensitization to nickel (45.5%vs 8.8%, OR 8.64, CI 5.67–13.17) and fragrance mix (29.0%vs 14.0%, OR 2.51, CI 1.60–3.91) and the corresponding intolerance of fashion jewelry and fragrances. Contact sensitization decreased with increasing degree of occupational training (unskilled 45.9%, apprenticeship 40.1%, technical college 40.4%, and school of engineering 12.5%; P=0.023; trend test P=0.042). Significant associations of contact sensitization and presence of allergen-specific IgE antibodies, atopic eczema, or psoriasis were not observed. Frequency estimates for the general adult population based on these findings were 28.0% for overall contact sensitization and 11.4% for fragrance mix, 9.9% for nickel, and 3.2% for thimerosal. Conclusions: It is concluded that contact allergy is influenced by sociodemographic parameters and plays an important role in the general population.