Department of Psychiatry, Tokyo Metropolitan Health and Medical Treatment Corporation, Ebara Hospital, Ota, Tokyo 145-0065, Japan; Department of Emergency and Critical Care Medicine, The University of Tokyo Hospital, Bunkyou, Tokyo 113-8655, Japan.
Neurosci Biobehav Rev. 2013 Sep;37(8):1692-701. doi: 10.1016/j.neubiorev.2013.04.019. Epub 2013 Jun 2.
Prevalence and symptoms of attention-deficit hyperactivity disorder (ADHD) change with advancing age. However, neurochemical background of such age-related change is yet to be elucidated. We therefore conducted a meta-analysis of 16 proton magnetic resonance spectroscopy studies comprising 270 individuals with ADHD and 235 controls. Standardized mean differences were calculated and used as an effect size. Sensitivity analyses and meta-regression to explore the effect of age on neurochemical abnormality were performed. A random effects model identified a significantly higher-than-normal N-acetylaspartate (NAA) in the medial prefrontal cortex (mPFC), but no significant differences of other metabolites in that area. No significant difference in metabolite levels was demonstrated in any other region. Sensitivity analysis of children with ADHD revealed significantly higher-than-normal NAA, whereas no significant difference was found in adults with ADHD. Meta-regression revealed significant correlation between advanced age and normal levels of NAA in the mPFC, suggesting that age-dependent abnormality of NAA level in the mPFC is a potential neural basis of age-related change of symptoms of ADHD.
注意力缺陷多动障碍（ADHD）的患病率和症状随年龄增长而变化。然而，这种与年龄相关的变化的神经化学背景尚不清楚。因此，我们对包括 270 名 ADHD 患者和 235 名对照在内的 16 项质子磁共振波谱研究进行了荟萃分析。计算了标准化均数差值，并用作效应量。进行了敏感性分析和荟萃回归，以探讨年龄对神经化学异常的影响。随机效应模型确定了内侧前额叶皮质（mPFC）中高于正常水平的 N-乙酰天冬氨酸（NAA），但该区域其他代谢物无显著差异。在其他任何区域均未显示出代谢物水平的显著差异。对 ADHD 儿童的敏感性分析显示，NAA 高于正常水平，而 ADHD 成人则无显著差异。荟萃回归显示，mPFC 中年龄与 NAA 正常水平之间存在显著相关性，这表明 mPFC 中 NAA 水平的年龄依赖性异常是 ADHD 症状与年龄相关变化的潜在神经基础。
