Department of Psychology and Neuroscience, University of Colorado, Boulder, CO, USA; Institute for Behavioral Genetics, University of Colorado Boulder, CO, USA.
Department of Psychology, University of Minnesota, Minneapolis, MN, USA.
Drug Alcohol Depend. 2019 Sep 1;202:104-110. doi: 10.1016/j.drugalcdep.2019.04.027. Epub 2019 Jun 29.
Research indicates that early tobacco initiation increases risk for dependence, but despite this, early initiation is associated with slower transitions to escalated tobacco use. In contrast to these findings, other studies suggest that rapid escalated tobacco use is associated with increased dependence outcomes.
Our sample was comprised of 5668 twins (2834 twin-pairs, mean age: 26.89, s.d = 4.42, 53.67% female, 57.69% monozygotic) from Colorado and Minnesota twin cohorts. We assessed the associations between 1) age of tobacco initiation and the speed of transitions (latency) to tobacco problem use and dependence and the associations between 2) age of initiation and latencies to tobacco problem use and dependence with tobacco dependence symptom severity. To further understand the etiological unfolding of these processes, we conducted univariate twin models and causally informative co-twin control models.
After adjustment for covariates, we found that early tobacco initiation was associated with a slower transition from initiation to problem use but a faster transition from problem use to dependence. Additionally, we found that earlier initiation and faster transitions to tobacco problem use and dependence predicted greater tobacco dependence severity within twin pairs (consistent with causal influences). The contribution of shared genetic and environmental factors was also evident for these relationships.
Our study further disentangles the role of early initiation with transition times to tobacco problem use and dependence. In addition to common risk factors, we found potential causal roles for early tobacco initiation and rapid escalated tobacco use with increased risk for tobacco dependence severity.
研究表明，早期吸烟会增加对尼古丁的依赖风险，但尽管如此，早期吸烟与向更严重的吸烟行为转变的速度较慢有关。与这些发现相反，其他研究表明，快速升级的烟草使用与依赖程度增加有关。
我们的样本包括来自科罗拉多州和明尼苏达州双胞胎队列的 5668 对双胞胎（2834 对双胞胎，平均年龄：26.89，标准差=4.42，53.67%为女性，57.69%为同卵双胞胎）。我们评估了 1）吸烟起始年龄与向烟草问题使用和依赖转变的速度（潜伏期）之间的关联，以及 2）吸烟起始年龄与向烟草问题使用和依赖的潜伏期与烟草依赖症状严重程度之间的关联。为了进一步了解这些过程的病因学发展，我们进行了单变量双胞胎模型和因果信息双胞胎控制模型。
在调整协变量后，我们发现早期吸烟与从起始吸烟向问题吸烟的转变较慢，但与从问题吸烟向依赖的转变较快有关。此外，我们发现更早的吸烟和更快的向烟草问题使用和依赖的转变预测了双胞胎内更大的烟草依赖严重程度（与因果影响一致）。共享遗传和环境因素的作用也在这些关系中显现出来。
我们的研究进一步阐明了早期吸烟与向烟草问题使用和依赖的转变时间之间的关系。除了共同的风险因素外，我们还发现了早期吸烟和快速升级的烟草使用与烟草依赖严重程度增加的潜在因果作用。
