Department of Interdisciplinary Social Science, Utrecht University, the Netherlands.
Interdisciplinary Center Psychopathology and Emotion Regulation, Department of Psychiatry, University Medical Center of Groningen, University of Groningen, the Netherlands.
Soc Sci Med. 2023 Nov;336:116254. doi: 10.1016/j.socscimed.2023.116254. Epub 2023 Sep 20.
Recent studies suggest that smoking and lower educational attainment may have genetic influences in common. However, little is known about the mechanisms through which genetics contributes to educational inequalities in adolescent and young adult smoking. Common genetic liabilities may underlie cognitive skills associated with both smoking and education, such as IQ and effortful control, in line with indirect health-related selection explanations. Additionally, by affecting cognitive skills, genes may predict educational trajectories and hereby adolescents' social context, which may be associated with smoking, consistent with social causation explanations. Using data from the Dutch TRAILS Study (N = 1581), we estimated the extent to which polygenic scores (PGSs) for ever smoking regularly (PGS) and years of education (PGS) predict IQ and effortful control, measured around age 11, and whether these cognitive skills then act as shared predictors of smoking and educational level around age 16, 19, 22, and 26. Second, we assessed if educational level mediated associations between PGSs and smoking. Both PGSs were associated with lower effortful control, and PGS also with lower IQ. Lower IQ and effortful control, in turn, predicted having a lower educational level. However, neither of these cognitive skills were directly associated with smoking behaviour after controlling for covariates and PGSs. This suggests that IQ and effortful control are not shared predictors of smoking and education (i.e., no indirect health-related selection related to cognitive skills). Instead, PGS and PGS, partly through their associations with lower cognitive skills, predicted selection into a lower educational track, which in turn was associated with more smoking, in line with social causation explanations. Our findings suggest that educational differences in the social context contribute to associations between genetic liabilities and educational inequalities in smoking.
最近的研究表明，吸烟和受教育程度较低可能有共同的遗传影响。然而，对于遗传因素如何导致青少年和年轻成人吸烟的教育不平等，人们知之甚少。常见的遗传缺陷可能与吸烟和教育都相关的认知技能有关，例如智商和努力控制，这符合间接与健康相关的选择解释。此外，通过影响认知技能，基因可能预测教育轨迹，并由此预测青少年的社会环境，而这可能与吸烟有关，这符合社会因果关系解释。使用荷兰 TRAILS 研究（N=1581）的数据，我们估计了终身吸烟（PGS）和受教育年限（PGS）的多基因评分（PGS）预测智商和努力控制的程度，这些都在 11 岁左右测量，以及这些认知技能是否随后成为 16 岁、19 岁、22 岁和 26 岁左右吸烟和教育水平的共同预测因素。其次，我们评估了教育水平是否在 PGS 与吸烟之间的关联中起中介作用。这两种 PGS 都与努力控制能力较低有关，PGS 也与智商较低有关。较低的智商和努力控制能力反过来又预示着教育水平较低。然而，在控制了协变量和 PGS 后，这些认知技能中没有一个与吸烟行为直接相关。这表明，智商和努力控制能力不是吸烟和教育的共同预测因素（即，与认知技能无关的间接与健康相关的选择）。相反，PGS 和 PGS 部分通过与较低的认知技能相关联，预测了进入较低教育轨道的选择，而这又与更多的吸烟有关，这符合社会因果关系解释。我们的研究结果表明，社会环境中的教育差异导致遗传易感性与吸烟的教育不平等之间的关联。
