Showing papers by "Allan Linneberg published in 2003"

IgG antibodies against microorganisms and atopic disease in Danish adults: the Copenhagen Allergy Study.

Abstract: Background: Seropositivity to food-borne and orofecal microorganisms (hepatitis A virus, Helicobacter pylori , and Toxoplasma gondii ), which are considered to be markers of poor hygiene, has been reported to be associated with a lower prevalence of atopy. In contrast, colonization of the gut with Clostridium difficile , a potential intestinal bacterial pathogen, in early childhood may be associated with a higher prevalence of atopy. Objective: The objective of this study was to investigate the association between atopy and exposure to 2 groups of food-borne and orofecal microorganisms: (1) markers of a poor hygiene and (2) intestinal bacterial pathogens. Methods: A cross-sectional population-based study of 15- to 69-year-olds living in Copenhagen, Denmark, was carried out in 1990 to 1991. Atopy was defined as a positive test result for specific IgE to at least 1 of 6 inhalant allergens. Exposure to microorganisms was assessed as IgG seropositivity to microorganisms. Results: Seropositivity to 2 or 3 markers of poor hygiene (hepatitis A virus, H pylori , and T gondii ) was associated with a lower prevalence of atopy (adjusted odds ratio, 0.5; 95% CI, 0.3 to 0.8). In contrast, seropositivity to 2 or 3 intestinal bacterial pathogens ( C difficile , Campylobacter jejuni , and Yersinia enterocolitica ) was associated with a higher prevalence of atopy (adjusted odds ratio, 1.7; 95% CI, 1.2 to 2.6). Conclusion: Exposure to markers of poor hygiene was associated with a lower prevalence of atopy, whereas exposure to intestinal bacterial pathogens was associated with a higher prevalence of atopy. These findings raise the hypothesis that different groups of food-borne and orofecal microorganisms may have different effects on the risk of atopy. (J Allergy Clin Immunol 2003;111:847-53.)

Smoking might be a risk factor for contact allergy.

Abstract: Background: Contact allergy is a major public health problem in industrialized countries. Hitherto, known risk factors for contact allergy have mainly included increased exposure to allergens. There are no published data on the relation between smoking and contact allergy. Objective: To investigate the association between smoking and contact allergy. Methods: The study population comprised a cross-sectional, general population-based sample of 15- to 69-year-old persons living in Copenhagen, Denmark. A total of 1056 persons (73.6% of the invited) were given a patch test (TRUE test). Contact allergy was defined as a positive patch test result to at least 1 of 23 allergens. Nickel contact allergy was defined as a positive patch test reaction to nickel. Allergic nickel contact dermatitis was defined as a history of eczema on exposure to metallic objects and a positive patch test reaction to nickel. A detailed smoking history was obtained in a questionnaire. Results: Contact allergy (adjusted odds ratio, 1.8; 95% CI, 1.2 to 2.9), nickel contact allergy (adjusted odds ratio, 2.7; 95% CI, 1.4 to 5.2), and allergic nickel contact dermatitis (adjusted odds ratio, 3.0; 95% CI, 1.5 to 6.2) were significantly associated with a smoking history of more than 15 pack-years. Moreover, these associations showed a significant dose-response relation, and they were independent of sex, age, and exposure to nickel, as reflected by a history of ear piercing. Conclusions: These data raise the hypothesis that smoking increases the risk of contact allergy. Further epidemiologic studies and investigations into the possible mechanisms are warranted. (J Allergy Clin Immunol 2003;111:980-4.)

The relationship of alcohol consumption to total immunoglobulin E and the development of immunoglobulin E sensitization: the Copenhagen Allergy Study

Abstract: Summary Background Several studies in patient populations have reported a positive association between alcohol consumption and serum total IgE. Furthermore, we have previously reported a positive association between alcohol consumption and the prevalence of skin prick test (SPT positivity) to inhalant allergens in a population-based cross-sectional study. Objective To investigate the relationship of alcohol consumption to levels of serum total IgE and the development of IgE sensitization to inhalant allergens. Methods In 1990, self-reported consumption of alcohol, serum total IgE, SPT positivity and specific IgE positivity to inhalant allergens were assessed in 1112 subjects, aged 15–69 years, participating in a population-based cross-sectional study in Copenhagen, Denmark. In 1998, they were invited to a follow-up and 734 were re-examined (participation rate 69.0%). Adjustment for potential confounders was performed by using multivariable regression analyses. Results In non-atopic (specific IgE negative) subjects there was a positive association between alcohol consumption and the concentration of total IgE (P = 0.001). During the follow-up period, 45 and 33 subjects developed SPT positivity and specific IgE positivity, respectively. There was no significant association between alcohol consumption and the development of SPT positivity or specific IgE positivity. However, the risk of developing SPT positivity tended to increase with increasing consumption of alcohol (P = 0.055). Conclusions This epidemiological study confirms that alcohol consumption has an influence on levels of serum total IgE. A significant association between alcohol consumption and the development of IgE sensitization was not established. However, there seems to be a lack epidemiological data on this issue.

Pets in the home and the development of pet allergy in adulthood. The Copenhagen Allergy Study.

Abstract: Background: The aim of the study was to investigate the association between exposure to cat and dog in the home and the development (incidence) of IgE sensitization to cat and dog. Methods: Participants in a population-based study of 15–69-year-olds in 1990 were invited to a follow-up in 1998. Serum IgE antibodies against common inhalant allergens was assessed in 734 subjects (participation rate 69.0%) on two occasions 8 years apart. Information about current or previous keeping of cats and dogs in the home was obtained in a questionnaire at baseline. Results: A cat in the home currently was significantly associated with the development of IgE sentisization to cat (adjusted odds ratio 8.4, 95% confidence interval (CI) 1.7–42.7). Moreover, an atopic predisposition in terms of IgE sensitization to allergens other than cat at baseline was an independent risk factor for the development of IgE sensitization to cat. A dog in the home was not significantly associated with the development of IgE sensitization to dog. Conclusions: In this adult population, exposure to a cat in the home increased the risk of developing IgE sensitization to cat. More prospective data are needed on this issue.