Department of Biology, Colgate University, Hamilton, NY, USA.
School of Public Health, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
Clin Exp Allergy. 2017 Oct;47(10):1299-1308. doi: 10.1111/cea.12995. Epub 2017 Sep 4.
Epidemiological evidence from developed countries indicates that Helicobacter pylori infection correlates with a reduced risk of atopy and allergic disorders; however, limited data are available from low-income countries.
We examined associations between H. pylori infection in early childhood and atopy and reported allergic disorders at the age of 6.5 years in an Ethiopian birth cohort.
A total of 856 children (85.1% of the 1006 original singletons in a population-based birth cohort) were followed up at age six and half years. An interviewer-led questionnaire administered to mothers provided information on demographic and lifestyle variables. Questions on allergic disease symptoms were based on the International Study of Asthma and Allergies in Children (ISAAC) core allergy and environmental questionnaire. Serum samples were analysed for total IgE levels and anti-H. pylori cytotoxin-associated gene A (CagA) IgG antibody using commercially available ELISA kits. Stool samples were analysed for H. pylori antigen using a rapid immunochromatographic test. The independent effects of H. pylori infection (measured at age of 3, 5 and 6.5 years) on prevalence and incidence of atopy and reported allergic disorders (measured at age of 6.5 years) were determined using multiple logistic regression.
In cross-sectional analysis, current H. pylori infection at age 6.5 years was inversely, though not significantly, related to prevalence of atopy and "any allergic condition" at age 6.5 years. However, detection of H. pylori infection at any point up to age 6.5 years was associated with a significantly reduced odds of both atopy and "any allergic condition" (adjusted OR AOR, 95% CI, 0.54; 0.32-0.92, P = .02, and .31; 0.10-0.94, P = .04, respectively). In longitudinal analyses, H. pylori infection at age 3 was inversely associated with incidence of atopy (AOR, 95% CI, 0.49; 0.27-0.89, P = .02). Furthermore, among H. pylori-infected children, those with a CagA+ strain had a more pronounced reduction in odds of atopy (AOR = 0.35 vs 0.63 for CagA+ vs CagA-), and this reduction reached borderline significance.
These data are consistent with the hypothesis that early exposure to H. pylori is inversely associated with atopy and allergic conditions. A possible modest protective association against atopy was observed in those infected with a more virulent CagA+ strain of H. pylori.
来自发达国家的流行病学证据表明，幽门螺杆菌感染与变应性和过敏性疾病的风险降低有关；然而，来自低收入国家的数据有限。
我们在埃塞俄比亚出生队列中检查了儿童早期幽门螺杆菌感染与特应性和 6.5 岁时报告的过敏性疾病之间的关联。
共有 856 名儿童（1006 名原始单胎出生队列中的 85.1%）在 6 岁半时接受了随访。对母亲进行的访谈者主导的问卷调查提供了人口统计学和生活方式变量的信息。过敏疾病症状的问题基于国际儿童哮喘和过敏研究（ISAAC）核心过敏和环境问卷。使用市售的 ELISA 试剂盒分析血清样本中的总 IgE 水平和抗幽门螺杆菌细胞毒素相关基因 A（CagA）IgG 抗体。使用快速免疫层析试验分析粪便样本中的幽门螺杆菌抗原。使用多变量逻辑回归确定幽门螺杆菌感染（在 3、5 和 6.5 岁时测量）对 6.5 岁时特应性和报告的过敏性疾病（在 6.5 岁时测量）的患病率和发病率的独立影响。
在横断面分析中，6.5 岁时当前的幽门螺杆菌感染与 6.5 岁时特应性和“任何过敏状况”的患病率呈负相关，但无统计学意义。然而，在 6.5 岁之前的任何时间检测到幽门螺杆菌感染与特应性和“任何过敏状况”的几率显著降低（调整后的比值比 AOR，95%CI，0.54；0.32-0.92，P=0.02 和.31；0.10-0.94，P=0.04）。在纵向分析中，3 岁时的幽门螺杆菌感染与特应性的发生率呈负相关（AOR，95%CI，0.49；0.27-0.89，P=0.02）。此外，在幽门螺杆菌感染的儿童中，CagA+菌株的感染与特应性几率的降低更为明显（AOR=0.35 与 CagA+与 CagA-相比，0.63），且这种降低具有边缘显著性。
这些数据与早期接触幽门螺杆菌与特应性和过敏性疾病呈负相关的假设一致。在感染更具毒力的 CagA+菌株的幽门螺杆菌的儿童中，观察到对特应性的适度保护关联。
