Branstetter Steven A, Mercincavage Melissa, Muscat Joshua E
Department of Biobehavioral Health, The Pennsylvania State University, University Park, PA, USA.
Addiction. 2014 Jun;109(6):1005-12. doi: 10.1111/add.12515. Epub 2014 Mar 19.
The time to first cigarette (TTFC) of the day is an indicator of nicotine intake in adults and adolescents. However, the relation between TTFC and biological markers of nicotine addiction and health risk in youths has not been well described. The current study examined whether an earlier TTFC predicts higher levels of a tobacco-specific carcinogen, 4-(methylnitrosamino)-1-(3-pyridal)-1 (NNAL), in regular and intermittent adolescent smokers and if this relation is mediated by nicotine intake (measured by cotinine) or cigarettes per day (CPD).
A cross-sectional analysis of a nationally representative subsample of adolescents.
A general community sample from the 2007-08 and 2009-10 National Health and Nutrition and Examination Survey.
A total of 215 adolescents in the United States between the ages of 12 and 19 years who reported smoking at least once in the 5 days prior to data collection.
The primary outcome measure was urinary levels of NNAL.
In both regular and intermittent smokers, earlier TTFC was associated dose-dependently with higher levels of NNAL (P < 0.03 in both cases). TTFC had an indirect effect on NNAL, mediated by nicotine intake (cotinine) in both regular [β = -0.08, standard error (SE) = 0.03, 95% confidence interval (CI) = -0.15, -0.03] and intermittent (β = -0.02, SE = 0.01, 95% CI = -0.05, -0.002) smokers. CPD was not found to be an important mediator of the relation between TTFC and NNAL.
Time between waking and the first cigarette of the day is correlated in daily and non-daily adolescent smokers with overall nicotine and therefore carcinogen intake.
一天中首次吸烟时间（TTFC）是成年人和青少年尼古丁摄入量的一个指标。然而，TTFC与青少年尼古丁成瘾生物标志物及健康风险之间的关系尚未得到充分描述。本研究调查了在规律和间歇性吸烟的青少年中，更早的TTFC是否预示着更高水平的一种烟草特异性致癌物4-（甲基亚硝胺基）-1-（3-吡啶基）-1（NNAL），以及这种关系是否由尼古丁摄入量（通过可替宁测量）或每日吸烟量（CPD）介导。
对具有全国代表性的青少年子样本进行横断面分析。
来自2007 - 08年和2009 - 10年国家健康与营养检查调查的一般社区样本。
美国共有215名年龄在12至19岁之间的青少年，他们在数据收集前5天内报告至少吸烟一次。
主要结局指标是尿中NNAL水平。
在规律和间歇性吸烟者中，更早的TTFC均与更高水平的NNAL呈剂量依赖性相关（两种情况均P < 0.03）。TTFC对NNAL有间接影响，在规律吸烟者[β = -0.08，标准误（SE）= 0.03，95%置信区间（CI）= -0.15，-0.03]和间歇性吸烟者（β = -0.02，SE = 0.01，95% CI = -0.05，-0.002）中均由尼古丁摄入量（可替宁）介导。未发现CPD是TTFC与NNAL之间关系的重要介导因素。
在每日和非每日吸烟的青少年中，醒来至当日第一支烟的时间与总体尼古丁及因此的致癌物摄入量相关。
