Instituto de Saúde Coletiva, Universidade Federal da Bahia, Salvador, Brazil.
Rev Panam Salud Publica. 2010 Dec;28(6):405-11. doi: 10.1590/s1020-49892010001200001.
This study aimed to explore the association between asthma and atopy in a cohort of children living in a large urban center in Brazil. Atopy was defined by the presence of allergen-specific IgE in serum or by a positive skin prick test.
In a sample of 1 445 Brazilian children, the association between the prevalence of asthma, skin prick test positivity, and allergen-specific IgE in serum was investigated.
The prevalence of asthma was 22.6%. The presence of serum allergen-specific IgE was frequent in asthmatics and nonasthmatics, and the prevalence of asthma increased only with levels of allergen-specific IgE > 3.5 kilounits/L. The proportion of asthma attributable to atopy was estimated to be 24.5% when atopy was defined by the presence of allergen-specific IgE. With a given level of specific IgE, no association between skin test reactivity and asthma was observed. Skin prick tests were less sensitive than specific IgE for detection of atopy.
Most asthma cases in an urban underprivileged setting in Brazil were not attributable to atopy. This observation has important implications for understanding the risk factors for the asthma epidemic in Latin America.
本研究旨在探讨巴西一个大城市中心的儿童群体中哮喘与过敏症之间的关联。过敏症通过血清中过敏原特异性 IgE 的存在或皮试阳性来定义。
在一个包含 1445 名巴西儿童的样本中，调查了哮喘、皮肤点刺试验阳性和血清中过敏原特异性 IgE 之间的相关性。
哮喘的患病率为 22.6%。在哮喘患者和非哮喘患者中，血清过敏原特异性 IgE 的存在较为常见，并且只有当过敏原特异性 IgE > 3.5 千单位/L 时，哮喘的患病率才会增加。当过敏症通过过敏原特异性 IgE 的存在来定义时，过敏症引起的哮喘比例估计为 24.5%。在特定的 IgE 水平下，皮肤试验反应性与哮喘之间没有关联。皮试比特异性 IgE 对过敏症的检测敏感性较低。
巴西城市贫困地区的大多数哮喘病例与过敏症无关。这一观察结果对理解拉丁美洲哮喘流行的危险因素具有重要意义。
