Division of Emergency Medicine, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA.
Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
Int J Environ Res Public Health. 2020 Feb 12;17(4):1157. doi: 10.3390/ijerph17041157.
: Cotinine is the preferred biomarker to validate levels of tobacco smoke exposure (TSE) in children. Compared to enzyme-linked immunosorbent assay methods (ELISA) for quantifying cotinine in saliva, the use of liquid chromatography tandem mass spectrometry (LC-MS/MS) has higher sensitivity and specificity to measure very low levels of TSE. We sought to compare LC-MS/MS and ELISA measures of cotinine in saliva samples from children overall and the associations of these measures with demographics and TSE patterns. : Participants were nonsmoking children (N = 218; age mean (SD) = 6.1 (5.1) years) presenting to a pediatric emergency department. Saliva samples were analyzed for cotinine using both LC-MS/MS and ELISA. Limit of quantitation (LOQ) for LC-MS/MS and ELISA was 0.1 ng/ml and 0.15 ng/ml, respectively. Intraclass correlations (ICC) across methods = 0.884 and was consistent in sex and age subgroups. The geometric mean (GeoM) of LC-MS/MS = 4.1 (range: < LOQ - 382 ng/mL; 3% < LOQ) which was lower ( < 0.0001) than the ELISA GeoM = 5.7 (range: < LOQ - 364 ng/mL; 5% < LOQ). Similar associations of cotinine concentrations with age ( < -0.10, < 0.0001), demographic characteristics (e.g., income), and number of cigarettes smoked by caregiver ( > 0.07, < 0.0001) were found regardless of cotinine detection method; however, cotinine associations with sex and race/ethnicity were only found to be significant in models using LC-MS/MS-derived cotinine. : Utilizing LC-MS/MS-based cotinine, associations of cotinine with sex and race/ethnicity of child were revealed that were not detectable using ELISA-based cotinine, demonstrating the benefits of utilizing the more sensitive LC-MS/MS assay for cotinine measurement when detecting low levels of TSE in children.
: 可铁宁是验证儿童烟草烟雾暴露（TSE）水平的首选生物标志物。与用于定量唾液中可铁宁的酶联免疫吸附测定法（ELISA）相比，液相色谱串联质谱法（LC-MS/MS）在测量非常低水平的 TSE 方面具有更高的灵敏度和特异性。我们旨在比较 LC-MS/MS 和 ELISA 测量唾液样本中可铁宁的方法，并评估这些方法与人口统计学和 TSE 模式的相关性。 : 参与者为非吸烟儿童（N=218；年龄平均（SD）=6.1（5.1）岁），他们就诊于儿科急诊室。使用 LC-MS/MS 和 ELISA 对唾液样本进行可铁宁分析。LC-MS/MS 和 ELISA 的定量下限（LOQ）分别为 0.1 ng/ml 和 0.15 ng/ml。两种方法的组内相关系数（ICC）=0.884，且在性别和年龄亚组中一致。LC-MS/MS 的几何平均值（GeoM）=4.1（范围：<LOQ-382ng/mL；3%<LOQ），低于 ELISA 的 GeoM=5.7（范围：<LOQ-364ng/mL；5%<LOQ）（<0.0001）。无论使用哪种可铁宁检测方法，可铁宁浓度与年龄（<0.10，<0.0001）、人口统计学特征（如收入）和照顾者吸烟的香烟数量（>0.07，<0.0001）之间均存在相似的相关性；然而，只有在使用 LC-MS/MS 衍生的可铁宁时，可铁宁与儿童性别和种族/民族的相关性才具有统计学意义。 : 利用基于 LC-MS/MS 的可铁宁，揭示了与儿童性别和种族/民族相关的可铁宁相关性，这些相关性使用 ELISA 无法检测到，这表明在检测儿童低水平 TSE 时，利用更敏感的 LC-MS/MS 检测可铁宁的方法具有优势。
