Skin reactivity and number of siblings

University Children's Hospital, Munich, Germany.
BMJ Clinical Research (Impact Factor: 14.09). 04/1994; 308(6930):692-5. DOI: 10.1136/bmj.308.6930.692
Source: PubMed

ABSTRACT To investigate the relation between skin test reactivity in children and number of siblings.
Cross sectional survey among schoolchildren aged 9-11 years. Skin prick tests in the children and self completion of written questionnaire by their parents.
5030 children in Munich and 2623 children in Leipzig and Halle, Germany.
Atopic status assessed by skin prick tests.
After possible confounders were controlled for, the prevalence of atopic sensitisation decreased linearly with increasing number of siblings (odds ratio = 0.96 for one sibling, 0.67 for five or more siblings; P = 0.005). In atopic children the severity of the skin test reaction as assessed by the weal size was not associated with the number of siblings.
Factors directly or indirectly related to the number of siblings may decrease the susceptibility of children to become atopic. Thus, declining family size may in part contribute to the increased prevalence of atopic diseases reported in Western countries over the past few decades.

  • Source
    • "Following prior research on the hygiene hypothesis (Matricardi, 1997; Riedler et al., 2001; Shaheen et al., 1996; Strachan, 1989; von Mutius et al., 1994), four measures of microbial exposures were considered: household size, the number of infections experienced during the first year of infancy, the presence of older siblings, and household pathogen exposures. First, household size included persons present and persons absent from the household during the baseline survey in 1983. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Infancy represents a window of development during which long-term immunological functioning can be influenced. In this study, we evaluate proxies of microbial exposures in infancy as predictors of interleukin-4 (IL-4) in young adulthood. IL-4 is an immunoregulatory cytokine that plays a role in the pathogenesis of atopic and allergic diseases. Data were obtained from 1,403 participants in the Cebu Longitudinal Health and Nutrition Survey, an ongoing population-based study in the Philippines. Relationships between microbial and nutritional environments in infancy and plasma IL-4 concentrations in adulthood were evaluated using tobit regression models. Having older siblings and more episodes of respiratory illness in infancy significantly predicted lower concentrations of plasma IL-4 in adulthood. Unexpectedly, more episodes of diarrheal illness in infancy were associated with higher IL-4 in adulthood. Interactions between a composite household pathogen exposure score and the duration of exclusive breastfeeding approached significance. This interaction showed that the negative association between household pathogen exposure in infancy and adult IL-4 was only significant for individuals who had been exclusively breastfed for a short duration of time. Finally, currently living in an urban household was unexpectedly, negatively associated with adult IL-4. Associations were independent of early nutrition, socioeconomic status (SES), and urbanicity, as well as current measures of infection, body fat, SES, and smoking. This study builds on a growing body of literature demonstrating that early ecological conditions have long-term effects on human biology by providing evidence that multiple proxies of microbial exposures in infancy are associated with adult IL-4.
    American Journal of Human Biology 07/2012; 24(4):446-53. DOI:10.1002/ajhb.22244 · 1.93 Impact Factor
  • Source
    • "Since then, many epidemiological findings have supported this theory. For instance, living in a large family, attending day care early in life, and growing up on a farm or in a family with an anthroposophic lifestyle have shown to reduce the risk of asthma and allergies [13] [14] [15] [16] [17]. Recently, being exposed to food-borne and oro-fecal infections at early age was found to be associated with a decreased prevalence of hay fever and asthma [18]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The prevalence of allergic diseases has increased considerably over the last decades. The hygiene hypothesis has emerged, linking reduced microbial exposure and infections early in life with the development of allergic diseases. Especially some of currently available non-replicating infant vaccines are unlikely to mimic a natural infection-mediated immune response that protects against the development of allergic diseases. Moreover, several studies suggested infant vaccinations to increase the risk of allergic diseases. To determine whether infant vaccinations increase the risk of developing allergic disease. We searched MEDLINE from 1966 to March 2003 and bibliography lists from retrieved articles, and consulted experts in the field to identify all articles relating vaccination to allergy. We selected epidemiological studies with original data on the correlation between vaccination with diphtheria, pertussis, tetanus (DPT), measles, mumps, rubella (MMR) and Bacillus Calmette-Guérin (BCG) vaccine in infancy and the development of allergic diseases, and assessed their quality and validity. Methodological design and quality varied considerably between the studies we reviewed. Many studies did not address possible confounders, such as the presence of lifestyle factors, leaving them prone to bias. The studies that offer the stronger evidence, including the only randomized controlled trial at issue published to date, indicate that the infant vaccinations we investigated do not increase the risk of developing allergic disease. Furthermore, BCG does not seem to reduce the risk of allergies. The reviewed epidemiological evidence indicates that, although possibly not contributing to optimal stimulation of the immune system in infancy, current infant vaccines do not cause allergic diseases.
    Vaccine 10/2004; 22(25-26):3375-85. DOI:10.1016/j.vaccine.2004.02.033 · 3.49 Impact Factor
  • Source
    • "Epidemiological studies have demonstrated that the prevalence of atopic diseases is increasing in industrialized countries with a ''western'' life style. Moreover, it was found that large numbers of siblings , especially when sharing bedrooms, or early entry into day care reduces the risk of IgE-mediated allergies (von Mutius et al, 1994; von Mutius et al, 1994; Strachan, 1997; Kramer et al, 1999). The data suggest that infections during early childhood reduce the risk of unwanted TH2 responses. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Since the first description of the subpopulations of TH1 and TH2 cells, insights into the development and control of these cells as two polarized and physiologically balanced subsets have been generated. In particular, implications of the TH1-TH2 concept for TH cell-mediated skin disorders have been discovered. This article will review the basic factors that control the development of TH1 and TH2 cells, such as the cytokines IL-12 and IL-4 and transcription factors, the possible role of costimulatory molecules, and specialized dendritic cell populations. These regulatory mechanisms will be discussed in the context of polarized TH1 or TH2 skin disorders such as psoriasis and atopic dermatitis. Also presented are the principles that govern how chemokines and chemokine receptors recruit TH1 and TH2 cells to inflammatory sites and how they amplify these polarized TH cell responses. All of these concepts, including a novel role for IL-4-inducing TH1 responses, can contribute to the design of better therapeutic strategies to modulate TH cell-mediated immune responses.
    Journal of Investigative Dermatology Symposium Proceedings 02/2004; 9(1):5-14. DOI:10.1111/j.1087-0024.2004.00829.x · 3.73 Impact Factor
Show more


Available from