Department of Population Health Sciences, School of Public Health, Georgia State University, Atlanta, GA, USA.
Division of Laboratory Sciences, National Center for Environmental Health, U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA.
Nicotine Tob Res. 2023 Mar 22;25(4):616-623. doi: 10.1093/ntr/ntac056.
To date, no studies have evaluated the consistency of biomarker levels in people who smoke over a long-time period in real-world conditions with a large number of subjects and included use behavior and measures of nicotine metabolism. We evaluated the variability of biomarkers of nicotine exposure over approximately a 1-year period in people who exclusively smoke cigarettes, including intensity and recency of use and brand switching to assess impact on understanding associations with product characteristics.
Multivariate regression analysis of longitudinal repeated measures of urinary biomarkers of nicotine exposure from 916 adults in the Population Assessment of Tobacco and Health (PATH) Study with demographic characteristics and use behavior variables. Intraclass correlation coefficients (ICCs) were calculated to examine individual variation of nicotine biomarkers and the uncertainty of repeat measures at two time points (Waves 1 and 2).
Age, race, and urinary creatinine were significant covariates of urinary cotinine. When including use behavior, recency, and intensity of use were highly significant and variance decreased to a higher extent between than within subjects. The ICC for urinary cotinine decreased from 0.7530 with no use behavior variables in the model to 0.5763 when included. Similar results were found for total nicotine equivalents.
Urinary nicotine biomarkers in the PATH Study showed good consistency between Waves 1 and 2. Use behavior measures such as time since last smoked a cigarette and number of cigarettes smoked in the past 30 days are important to include when assessing factors that may influence biomarker concentrations.
The results of this study show that the consistency of the nicotine biomarkers cotinine and total nicotine equivalents in spot urine samples from Waves 1 to 2 of the PATH Study is high enough that these data are useful to evaluate the association of cigarette characteristics with biomarkers of exposure under real-world use conditions.
迄今为止，尚无研究在真实环境下，对大量人群进行长期、包括使用行为和尼古丁代谢测量的情况下，评估吸烟者生物标志物水平的一致性。我们评估了在仅吸烟的人群中，尼古丁暴露生物标志物在大约 1 年时间内的变化情况，包括使用强度和最近使用情况以及品牌转换，以评估其对理解与产品特性关联的影响。
使用人口烟草和健康评估（PATH）研究中的 916 名成年人尿液尼古丁暴露生物标志物的纵向重复测量数据进行多变量回归分析，包括人口统计学特征和使用行为变量。计算了个体间变异的内类相关系数（ICC），以检查两个时间点（波 1 和波 2）的尼古丁生物标志物的个体差异和重复测量的不确定性。
年龄、种族和尿肌酐是尿可替宁的重要协变量。当包括使用行为时，最近使用和使用强度是高度显著的，并且在受试者之间的差异程度降低。当包含在模型中时，尿可替宁的 ICC 从没有使用行为变量的模型中 0.7530 降低到 0.5763。总尼古丁当量的结果相似。
PATH 研究中的尿液尼古丁生物标志物在波 1 和波 2 之间显示出良好的一致性。使用行为测量，如最后吸烟的时间和过去 30 天内吸烟的数量，在评估可能影响生物标志物浓度的因素时非常重要。
本研究结果表明，PATH 研究中波 1 到波 2 之间的尼古丁生物标志物可替宁和总尼古丁当量的一致性足够高，这些数据可用于评估在实际使用条件下香烟特征与暴露生物标志物的关联。
