In this study, we assessed trends of serum cotinine levels over time among US children ages 3–11 years and compared the risk of asthma in groups exposed to passive tobacco smoke. We utilized National Health and Nutrition Examination Survey (NHANES) data collected from 2003 to 2014 (n = 8064). Serum cotinine level, household smoker status, asthma status, and sociodemographic information were extracted for multiple regression analyses. The adjusted biannual change in log (cotinine) in comparison to earlier NHANES survey cycles was − 0.196 (p < 0.001) overall, − 0.055 (p = 0.089) among children with household smoker(s), and − 0.129 (p < 0.001) among children without. The proportion of children living with household smokers decreased from 24.9% in the 2003–2004 cycle to 11.4% in the 2013–2014 cycle. The adjusted odds ratios (ORs) for asthma were 1.34 (95% confidence interval (CI): 1.00–1.80; 2nd tertile vs 1st tertile) and 1.69 (95%CI: 1.25–2.29; 3rd tertile vs1st tertile), respectively. Highly exposed asthmatic children, in the 3rd cotinine tertile (>0.13 ng/mL), were primarily Non-Hispanic Black (61.0%) and whose family incomes were below poverty guidelines. Overall results reveal passive smoke exposure level among children ages 3–11 in the US decreased over the study period. Nevertheless, higher exposure to passive smoke is still associated with higher odds of childhood asthma. Targeted smoking cessation interventions in clinical practices are needed to reduce tobacco smoke exposure and related asthma risk in children, particularly in low-income and minority groups.

在这项研究中，我们评估了3-11岁美国儿童中血清可替宁水平随时间的变化趋势，并比较了接触被动吸烟的人群中哮喘的风险。我们利用了2003年至2014年收集的国家健康和营养检查调查（NHANES）数据（n = 8064）。提取血清可替宁水平，家庭吸烟者状况，哮喘状况和社会人口统计学信息以进行多元回归分析。与较早的NHANES调查周期相比，调整后的log（可卡因）半年度变化 总体为-0.196（p <0.001）， 有家庭吸烟者的儿童为-0.055（p = 0.089），以及-0.129（p <0.001）。住户吸烟儿童的比例从2003–2004年周期的24.9％降至2013–2014年周期的11.4％。哮喘调整后的优势比（OR）分别为1.34（95％置信区间（CI）：1.00-1.80；第二三分位数与第一三分位数）和1.69（95％CI：1.25-2.29；第三三分位数与第一三分位数）。高度暴露的哮喘儿童，处于第三可替宁水平（> 0.13 ng / mL）中，主要是非西班牙裔黑人（61.0％），其家庭收入低于贫困线。总体结果显示，在研究期内，美国3-11岁儿童的被动烟暴露水平有所下降。然而，更多地接触被动烟仍然会增加儿童哮喘的几率。