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Objective: To assess the influence of the trajectory of weight gain from birth to adolescence on cardiovascular and metabolic risk. We studied childhood body mass index (BMI) trajectories from birth to age 14 years and cardiometabolic risk factors at age 14 years., Study Design: In total, 410 children with weight and height measurements were assessed from birth throughout childhood, from the Childhood Asthma Prevention Study, a prospective community-based cohort. BMI trajectory groups were determined by latent basis growth mixture models. Of these subjects, 190 had detailed cardiometabolic risk factors assessed at age 14 years., Results: Three BMI trajectory groups were identified; normal BMI, "early rising" excess BMI from 2 years, and "late rising" excess BMI from 5 years. Differences were found between normal and excess BMI in children at 14 years of age. In addition, children with an early rising BMI trajectory had statistically significantly higher central adiposity and a more atherogenic lipoprotein profile at age 14 years than children with a late rising BMI trajectory (P < .05). No differences between BMI trajectory groups in vascular structure or function was identified at age 14 years., Conclusions: Earlier onset of an elevated BMI trajectory persisting from birth to age 14 years results in an unfavorable cardiometabolic risk profile at age 14 years, including central adiposity and more atherogenic lipoproteins, independent of achieved BMI., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Viruses are frequently associated with acute exacerbations of asthma, but the extent to which they contribute to the level of day-to-day symptom control is less clear., Objective: We sought to explore the relationship between viral infections, host and environmental factors, and respiratory symptoms in children., Methods: Sixty-seven asthmatic children collected samples twice weekly for an average of 10 weeks. These included nasal wash fluid and exhaled breath for PCR-based detection of viral RNA, lung function measurements, and records of medication use and asthma and respiratory symptoms in the previous 3 days. Atopy, mite allergen exposure, and vitamin D levels were also measured. Mixed-model regression analyses were performed., Results: Human rhinoviruses (hRVs) were detected in 25.5% of 1232 nasal samples and 11.5% of breath samples. Non-hRV viruses were detected in less than 3% of samples. hRV in nasal samples was associated with asthma symptoms (cough and phlegm: odds ratio = 2.0; 95% CI = 1.4-2.86, P = .0001; wheeze and chest tightness: odds ratio = 2.34, 95% CI = 1.55-3.52, P < .0001) and with cold symptoms, as reported concurrently with sampling and 3 to 4 days later. No differences were found between the 3 hRV genotypes (hRV-A, hRV-B, and hRV-C) in symptom risk. A history of inhaled corticosteroid use, but not atopic status, mite allergen exposure, or vitamin D levels, modified the association between viruses and asthma symptoms., Conclusion: The detection of nasal hRV was associated with a significantly increased risk of day-to-day asthma symptoms in children. Host, virus genotype, and environmental factors each had only a small or no effect on the relationship of viral infections to asthma symptoms., (Copyright © 2014 American Academy of Allergy, Asthma & Immunology. All rights reserved.)

Background: Asthma and allergic sensitization to cats frequently coexist, although recent studies show less atopic disease among people who had pets in infancy. However, no longterm evaluations have been performed thus far., Objective: We sought to evaluate the relationship between cat ownership at different age periods (< 18, > 18, and both periods and atopic disease at age 28., Methods: Australian school children aged 8 to 10 years were recruited in 1982 and participated in follow-up surveys until 2002. Cat ownership was defined by surveys in 1992 and 2002 as having a cat before age 18 only, after age 18 only, or in both periods of life. Health outcomes were defined at a mean age of 28.5 years., Results: Complete data were available for 224 subjects, 50 of whom had a cat before 18 years of age only, 14 after age 18 only, and 70 in both periods. Compared with 90 subjects that never had a cat, having a cat before age 18 protected against atopy to outdoor allergens, airway hyperresponsiveness (AHR) to histamine, current wheeze, and current asthma (P < .05). In contrast, subjects who acquired their first cat after age 18 showed a trend toward higher prevalence rates for asthma symptoms and AHR (P > .10)., Conclusions: Having had a cat before 18 years of age protects against adult asthma and atopy.

Background: There are conflicting reports on the effect of BCG vaccination on the subsequent development of atopy and asthma. There are no data on the effects of neonatal BCG vaccination on cytokine responses of lymphocytes that are exposed in vitro to allergens., Objectives: We sought to test the hypothesis that neonatal BCG vaccination or, alternatively, evidence of an immunologic memory of this vaccination is associated with a reduced prevalence of allergic sensitization, asthma, eczema, and hay fever during childhood., Methods: An historical cohort study was conducted among 7- to 14-year-old children who were born in 2 districts in Sydney, Australia, and whose mothers were born in southeast Asia. One district had routinely administered BCG vaccination to infants born to overseas-born mothers and the other had not. Eligible subjects were identified from birth registers. Consenting subjects completed questionnaires, performed spirometric and airway hyperresponsiveness testing, and had allergen skin prick testing and tuberculin skin testing. Blood was collected to measure total serum IgE levels and for in vitro lymphocyte culture in the presence of an extract of house dust mite, the dominant allergen in this region, and purified protein derivative of Mycobacterium tuberculosis (tuberculin). IL-4, IL-5, IL-10, and IFN-gamma were measured in the culture supernatant., Results: The cohort included 309 BCG-vaccinated subjects and 442 non-BCG-vaccinated subjects. BCG-vaccinated subjects did not have a lower rate of allergic sensitization than nonvaccinated subjects. However, among the subgroup of subjects with a family history of rhinitis or eczema, BCG vaccination was associated with a lower prevalence of current asthma (defined as recent wheezing plus airway hyperresponsiveness; relative risk, 0.46; 95% CI, 0.22-0.95). BCG vaccination was also associated with lower levels of allergen-stimulated IL-10 production in vitro. Among the BCG-vaccinated subjects, the 44 (14.3%) who had tuberculin skin test reaction sizes of 5 mm or greater and the 31 (18.3%) who demonstrated an in vitro IFN-gamma response to purified protein derivative of M tuberculosis did not have lower rates of allergic sensitization and, overall, did not have a lower prevalence of allergic disease than tuberculin skin test or IFN-gamma nonreactors., Conclusion: We conclude that neonatal BCG vaccination has an effect on T-cell allergen responsiveness 7 to 14 years after vaccination and that among a subgroup of subjects with an inherited predisposition to allergic disease, this is associated with clinically relevant beneficial effects. The findings of this study encourage the view that external influences on the immune system in the neonatal period have consequences that extend into later childhood and influence the expression of asthma. Genetic factors are likely to modify the effect of those external factors.

In early life, asthma symptoms can occur intermittently or may not be severe enough to limit normal activities, which makes it difficult for the clinician to make reliable predictions and administer therapy with some precision. In the case of pediatric asthma, the identification of children who will experience the development of a clinically important illness that will impair their quality of life can be a complex process. The usual methods for describing this information include the prognostic statistics of sensitivity, specificity, likelihood ratio, and positive predictive value. The sensitivity, specificity, and likelihood ratio of various early markers of asthma have been calculated from several cohort studies. (J Allergy Clin Immunol 2000;106:S144-52.)

In early life, asthma symptoms can occur intermittently or may not be severe enough to limit normal activities, which makes it difficult for the clinician to make reliable predictions and administer therapy with some precision. In the case of pediatric asthma, the identification of children who will experience the development of a clinically important illness that will impair their quality of life can be a complex process. The usual methods for describing this information include the prognostic statistics of sensitivity, specificity, likelihood ratio, and positive predictive value. The sensitivity, specificity, and likelihood ratio of various early markers of asthma have been calculated from several cohort studies.

House dust mite (HDM) allergen exposure and its relation to HDM allergy and asthma was assessed in a case-control study conducted over three seasons in 74 Sydney schoolchildren, 33 of whom were allergic to HDM and 12 of whom had current asthma. In each season histamine inhalation tests and skin prick tests were performed, symptom questionnaires were administered, and dust samples were collected. The mean concentrations of HDM allergen (in micrograms of Der p 1 per gram of fine dust) were: bed, 38.9 (95% confidence interval [CI], 31.8 to 47.5); bedroom floor, 22.4 (95% CI, 18.3 to 27.5); and lounge room floor, 13.7 (95% CI, 10.7 to 17.6). The mean of the highest allergen concentration in each house was 51.0 (95% CI, 43.2 to 60.1). All but two subjects had at least one site in all seasons with an HDM allergen concentration greater than 10 micrograms/gm, the proposed threshold for asthma symptoms. Subjects with allergy to HDM, symptoms of asthma, or airway hyperresponsiveness did not have higher HDM allergen concentrations in their house. In this study we were unable to test hypotheses concerning proposed thresholds for risk of sensitization and for risk of asthma symptoms because virtually all subjects were exposed to HDM allergen levels above the proposed thresholds.