Division of Immunology, Allergy, and Rheumatology, Joe DiMaggio Children's Hospital, Hollywood, Fla.
Institutional Centers for Clinical and Translational Research, Boston Children's Hospital, Harvard Medical School, Boston, Mass.
J Allergy Clin Immunol. 2023 Dec;152(6):1677-1682. doi: 10.1016/j.jaci.2023.06.027. Epub 2023 Aug 3.
Few data on the relationships between environmental exposures, asthma morbidity, and systemic IL-6 inflammation exist.
We sought to determine whether baseline plasma IL-6 level is associated with increased asthma morbidity in children exposed to mouse allergen in inner-city classrooms.
Data from the longitudinal School Inner-City Asthma Studies of 215 children with asthma, aged 4 to 14 years and recruited from urban elementary schools, were analyzed. Given the unknown threshold of IL-6 risk levels and skewness of the distribution, the children were stratified into tertiles as follows: low baseline IL-6 level (<0.013 pg/mL), moderate baseline IL-6 level (0.013-0.302 pg/mL), and high baseline IL-6 level (>0.302 pg/mL). Relationships between plasma IL-6 level and body mass index (BMI) percentile, inflammatory markers, lung function, mouse allergen exposure, and asthma outcomes were assessed.
Cross-sectional analysis demonstrated that increasing IL-6 level was associated with higher BMI percentile (P < .0001), C-reactive protein level (P = .0006), and blood neutrophil count (P = .0024). IL-6 was not associated with type 2 inflammatory markers, including blood eosinophil count, allergic sensitization, or fractional exhaled nitric oxide level. Longitudinal analysis showed that children with high IL-6 levels had a higher number of days with asthma symptoms than did those children with moderate (incidence rate ratio = 1.74 [95% CI = 1.10-2.77]; P = .0187) or low (incidence rate ratio =1.83 [95% CI = 1.21-2.77]; P = .0043) IL-6 levels. Children with high IL-6 levels who were exposed to increasing levels of mouse allergen exhibited lower ratios of FEV value to forced vital capacity than did children with moderate IL-6 levels (β = -0.0044 [95% CI = -0.0073 to -0.0015]; pairwise interaction P = .0028) or low IL-6 levels (β = -0.0042 [95% CI = - 0.0070 to -0.0013]; pairwise interaction P = .0039).
Inner-city children with asthma and high plasma IL-6 levels are more likely to have an increased BMI, elevated C-reactive protein level, elevated blood neutrophil count, and greater asthma symptoms. High IL-6 level appears to increase susceptibility to the effects of classroom exposure to mouse allergen on lung function in urban children.
关于环境暴露、哮喘发病率和全身白细胞介素-6 炎症之间的关系，数据很少。
我们旨在确定基线血浆白细胞介素-6 水平是否与接触城市教室中鼠过敏原的儿童哮喘发病率增加有关。
对来自城市小学的 215 名年龄在 4 至 14 岁之间、患有哮喘的儿童进行了纵向城市内哮喘研究的数据分析。由于白细胞介素-6 风险水平的未知阈值和分布的偏态，儿童被分为三个三分位数组：低基线白细胞介素-6 水平（<0.013pg/mL）、中基线白细胞介素-6 水平（0.013-0.302pg/mL）和高基线白细胞介素-6 水平（>0.302pg/mL）。评估了血浆白细胞介素-6 水平与体重指数（BMI）百分位、炎症标志物、肺功能、鼠过敏原暴露和哮喘结局之间的关系。
横断面分析表明，白细胞介素-6 水平的升高与较高的 BMI 百分位（P<.0001）、C 反应蛋白水平（P=.0006）和血液中性粒细胞计数（P=.0024）相关。白细胞介素-6 与 2 型炎症标志物无相关性，包括血液嗜酸性粒细胞计数、过敏致敏或呼出一氧化氮分数。纵向分析显示，白细胞介素-6 水平较高的儿童出现哮喘症状的天数多于中（发病率比 1.74 [95%置信区间 1.10-2.77]；P=0.0187）或低（发病率比 1.83 [95%置信区间 1.21-2.77]；P=0.0043）白细胞介素-6 水平的儿童。暴露于不断增加的鼠过敏原水平且白细胞介素-6 水平较高的儿童的 FEV 值与用力肺活量的比值低于白细胞介素-6 水平中等（β=-0.0044 [95%置信区间-0.0073 至-0.0015]；两两交互 P=0.0028）或低（β=-0.0042 [95%置信区间-0.0070 至-0.0013]；两两交互 P=0.0039）的儿童。
患有哮喘的城市儿童如果血浆白细胞介素-6 水平较高，则更有可能出现 BMI 增加、C 反应蛋白水平升高、血液中性粒细胞计数升高和哮喘症状加重。高白细胞介素-6 水平似乎增加了对城市儿童教室接触鼠过敏原对肺功能影响的易感性。
