{
  "abstract": "Background It is well established that there are different asthma phenotypes, but whereas determinants of atopic asthma (AA) are well studied, little is known about non-atopic asthma (NAA). We compared risk factors for atopy, AA in atopics and NAA in non-atopics in children in a wide variety of countries.Methods Using four studies, across 23 countries, we assessed asthma status and atopy (skin prick tests) for children aged 6–17, plus risk factors from housing, heating, pets, family, diet and air quality categories. Using mixed-effects logistic regression models, we assessed risk factors over four pathways: pathway 1—non-atopic non-asthma to NAA; pathway 2—non-atopic non-asthma to atopy (no asthma); pathway 3—atopic non-asthma to AA; pathway 4—non-atopic non-asthma to AA. We compared the log odds of risk factors between pathways using the Pearson correlation coefficient (PCC).Results Our final sample of 32 741 children comprised 67% with neither atopy nor asthma, 15% with atopy but without asthma, 8% with AA and 10% with NAA. Risk factors were similar between pathway 1 and pathway 3 (PCC=0.81, 95% CI 0.68 to 0.94). In contrast, risk factors differed between pathway 2 and pathway 3 (PCC=−0.06, 95% CI −0.29 to 0.17).Discussion These findings indicate that although atopy increases the risk of asthma, the risk factors for subsequently developing asthma are generally the same in those with and without atopy. This raises important questions about the role of atopy in asthma, particularly whether it is an inherent part of the aetiological process or is coincidental.",
  "authors": [
    {
      "affiliations": [
        "Department of Medical Statistics, London School of Hygiene & Tropical Medicine, London, UK"
      ],
      "name": "Charlotte E Rutter"
    },
    {
      "affiliations": [
        "MRC/UVRI and LSHTM Uganda Research Unit, Entebbe, Uganda"
      ],
      "name": "Harriet Mpairwe"
    },
    {
      "affiliations": [
        "Institute of Health Sciences, Federal University of Bahia, Salvador, Brazil"
      ],
      "name": "Camila A Figueiredo"
    },
    {
      "affiliations": [
        "Department of Medical Statistics, London School of Hygiene & Tropical Medicine, London, UK"
      ],
      "name": "Mary Njoroge"
    },
    {
      "affiliations": [
        "Clinical Trials Unit, London School of Hygiene & Tropical Medicine, London, UK"
      ],
      "name": "Steven Robertson"
    },
    {
      "affiliations": [
        "Centre for Public Health Research, Massey University, Wellington, New Zealand"
      ],
      "name": "Hajar Ali"
    },
    {
      "affiliations": [
        "Centre for Public Health Research, Massey University, Wellington, New Zealand"
      ],
      "name": "Collin Brooks"
    },
    {
      "affiliations": [
        "Centre for Public Health Research, Massey University, Wellington, New Zealand"
      ],
      "name": "Jeroen Douwes"
    },
    {
      "affiliations": [
        "Fundacion Ecuatoriana Para La Investigacion en Salud, Quito, Ecuador",
        "School of Medicine, Universidad Internacional del Ecuador, Quito, Ecuador",
        "Institute of Infection and Immunity, St George’s University of London, London, UK"
      ],
      "name": "Philip J Cooper"
    },
    {
      "affiliations": [
        "Fundacion Ecuatoriana Para La Investigacion en Salud, Quito, Ecuador"
      ],
      "name": "Martha Chico"
    },
    {
      "affiliations": [
        "School of Medicine, Universidad Internacional del Ecuador, Quito, Ecuador",
        "Grups de Recerca d’America i Africa Llatines (GRAAL), Barcelona, Spain"
      ],
      "name": "Natalia Romero-Sandoval"
    },
    {
      "affiliations": [
        "PROAR, Federal University of Bahia, Salvador, Brazil"
      ],
      "name": "Álvaro A Cruz"
    },
    {
      "affiliations": [
        "MRC/UVRI and LSHTM Uganda Research Unit, Entebbe, Uganda"
      ],
      "name": "Pius Tumwesige"
    },
    {
      "affiliations": [
        "Centre for Data and Knowledge Integration for Health (CIDACS), Fiocruz, Bahia, Brazil"
      ],
      "name": "Mauricio L Barreto"
    },
    {
      "affiliations": [
        "Department of Medical Statistics, London School of Hygiene & Tropical Medicine, London, UK"
      ],
      "name": "Neil Pearce"
    },
    {
      "affiliations": [
        "Department of Medical Statistics, London School of Hygiene & Tropical Medicine, London, UK"
      ],
      "name": "Lucy Pembrey"
    },
    {
      "affiliations": [],
      "name": "the CAMERA Study Group"
    }
  ],
  "title": "Risk factors for atopic and non-atopic asthma in school-age children from high-income and low- and middle-income countries",
  "uid": "8b55453a-16f9-5aab-b0cd-cd3cfc8b1bb5"
}