Gillespie Nathan A, Neale Michael C, Bates Timothy C, Eyler Lisa T, Fennema-Notestine Christine, Vassileva Jasmin, Lyons Michael J, Prom-Wormley Elizabeth C, McMahon Katie L, Thompson Paul M, de Zubicaray Greig, Hickie Ian B, McGrath John J, Strike Lachlan T, Rentería Miguel E, Panizzon Matthew S, Martin Nicholas G, Franz Carol E, Kremen William S, Wright Margaret J
Virginia Institute for Psychiatric and Behavior Genetics, Virginia Commonwealth University, VA, USA.
QIMR Berghofer Medical Research Institute, QLD, Australia.
Addiction. 2018 Apr 24. doi: 10.1111/add.14252.
Disentangling the putative impact of cannabis on brain morphology from other comorbid substance use is critical. After controlling for the effects of nicotine, alcohol and multi-substance use, this study aimed to determine whether frequent cannabis use is associated with significantly smaller subcortical grey matter volumes.
Exploratory analyses using mixed linear models, one per region of interest (ROI), were performed whereby individual differences in volume (outcome) at seven subcortical ROIs were regressed onto cannabis and comorbid substance use (predictors).
Two large population-based twin samples from the United States and Australia.
A total of 622 young Australian adults [66% female; μ = 25.9, standard deviation SD) = 3.6] and 474 middle-aged US males (μ = 56.1 ) of predominately Anglo-Saxon ancestry with complete substance use and imaging data. Subjects with a history of stroke or traumatic brain injury were excluded.
Magnetic resonance imaging (MRI) and volumetric segmentation methods were used to estimate volume in seven subcortical ROIs: thalamus, caudate nucleus, putamen, pallidum, hippocampus, amygdala and nucleus accumbens. Substance use measurements included maximum nicotine and alcohol use, total life-time multi-substance use, maximum cannabis use in the young adults and regular cannabis use in the middle-aged males.
After correcting for multiple testing (P = 0.007), cannabis use was unrelated to any subcortical ROI. However, maximum nicotine use was associated with significantly smaller thalamus volumes in middle-aged males.
In exploratory analyses based on young adult and middle-aged samples, normal variation in cannabis use is unrelated statistically to individual differences in brain morphology as measured by subcortical volume.
区分大麻对脑形态的假定影响与其他共病物质使用的影响至关重要。在控制了尼古丁、酒精和多物质使用的影响后，本研究旨在确定频繁使用大麻是否与显著更小的皮质下灰质体积相关。
使用混合线性模型进行探索性分析，每个感兴趣区域（ROI）一个模型，将七个皮质下ROI的体积个体差异（结果）回归到大麻和共病物质使用（预测因子）上。
来自美国和澳大利亚的两个基于人群的大型双胞胎样本。
共有622名澳大利亚年轻成年人[66%为女性；μ = 25.9，标准差（SD）= 3.6]和474名美国中年男性（μ = 56.1），主要为盎格鲁-撒克逊血统，有完整的物质使用和成像数据。有中风或创伤性脑损伤病史的受试者被排除。
使用磁共振成像（MRI）和体积分割方法估计七个皮质下ROI的体积：丘脑、尾状核、壳核、苍白球、海马体、杏仁核和伏隔核。物质使用测量包括最大尼古丁和酒精使用量、终身多物质使用总量、年轻成年人中的最大大麻使用量和中年男性中的定期大麻使用量。
在进行多重检验校正（P = 0.007）后，大麻使用与任何皮质下ROI均无关联。然而，中年男性中最大尼古丁使用量与显著更小的丘脑体积相关。
在基于年轻成年人和中年样本的探索性分析中，大麻使用的正常变异在统计学上与通过皮质下体积测量的脑形态个体差异无关。
