Department of Psychology, University of Minnesota, Twin Cities, N218 Elliott Hall, 75 East River Parkway, Minneapolis, MN, 55455, USA.
Institute for Behavioral Genetics, and Department of Psychology & Neuroscience, University of Colorado Boulder, Boulder, USA.
Behav Genet. 2020 May;50(3):139-151. doi: 10.1007/s10519-020-09994-8. Epub 2020 Feb 8.
Externalizing psychopathology in early adolescence is a highly heritable risk factor for drug use, yet how it relates to marijuana use development is not well-characterized. We evaluate this issue in independent twin samples from Colorado (N = 2608) and Minnesota (N = 3630), assessed from adolescence to early adulthood. We used a biometric latent growth model of marijuana use frequency with data from up to five waves of assessment from ages 14 to 30, to examine change in marijuana use and its relationship with a factor model of adolescent externalizing psychopathology. The factor structure of adolescent externalizing psychopathology was similar across samples, as was the association between that common factor and early marijuana use (Minnesota r = 0.67 [0.60, 0.75]; Colorado r = 0.69 [0.59, 0.78]), and increase in use (Minnesota r = 0.18 [0.10, 0.26]; Colorado r = 0.20 [0.07, 0.34]). Early use was moderately heritable in both samples (Minnesota h = 0.57 [0.37, 0.79]; Colorado h = 0.42 [0.14, 0.73]). Increase in use was highly heritable in Minnesota (h = 0.82 [0.72, 0.88]), less so in Colorado (h = 0.22 [0.01, 0.66]), and shared environmental effects were larger in Colorado (c = 0.55 [0.14, 0.83]) than Minnesota (c = 0 [0, 0.06]). We found moderate genetic correlations between externalizing psychopathology and early use in both samples. Finally, additional analyses in the Minnesota sample indicated that marijuana use decreased during the late 20s. This decline is strongly heritable (h = 0.73 [0.49, 0.91]) and moderately negatively correlated with adolescent externalizing psychopathology (r = - 0.41 [- 0.54, - 0.28]). Adolescent externalizing psychopathology is genetically correlated with change in late adolescent marijuana use (late teens, early 20s), as well as maintenance of use in early adulthood (late 20 s) even after controlling for the effects of early use.
青少年早期的外化性精神病理学是药物使用的一个高度遗传风险因素，但它与大麻使用发展的关系尚未得到很好的描述。我们在来自科罗拉多州（N = 2608）和明尼苏达州（N = 3630）的独立双胞胎样本中评估了这个问题，这些样本在青少年期到成年早期进行了评估。我们使用大麻使用频率的生物计量潜变量增长模型，对从 14 岁到 30 岁的最多五次评估的数据进行了分析，以检验大麻使用的变化及其与青少年外化性精神病理学的因素模型的关系。青少年外化性精神病理学的因素结构在两个样本中相似，共同因素与早期大麻使用（明尼苏达州 r = 0.67 [0.60, 0.75]；科罗拉多州 r = 0.69 [0.59, 0.78]）和使用量的增加（明尼苏达州 r = 0.18 [0.10, 0.26]；科罗拉多州 r = 0.20 [0.07, 0.34]）之间存在关联。早期使用在两个样本中均具有中等的遗传可遗传性（明尼苏达州 h = 0.57 [0.37, 0.79]；科罗拉多州 h = 0.42 [0.14, 0.73]）。在明尼苏达州，使用量的增加具有高度的遗传可遗传性（h = 0.82 [0.72, 0.88]），在科罗拉多州则较低（h = 0.22 [0.01, 0.66]），而共同环境效应在科罗拉多州较大（c = 0.55 [0.14, 0.83]），而在明尼苏达州则较小（c = 0 [0, 0.06]）。我们在两个样本中均发现了外化性精神病理学与早期使用之间的中等遗传相关性。最后，在明尼苏达州样本中的进一步分析表明，大麻使用在 20 多岁后期有所减少。这种下降具有很强的遗传性（h = 0.73 [0.49, 0.91]），并且与青少年外化性精神病理学呈中度负相关（r = - 0.41 [- 0.54, - 0.28]）。青少年外化性精神病理学与青少年后期大麻使用的变化（青少年后期，20 岁出头）以及青少年后期（20 多岁后期）的使用维持具有遗传相关性，即使在考虑早期使用的影响后也是如此。
