The Mental Illness Research Education and Clinical Center, James J. Peters Veterans Affairs Medical Center, NY 10029, USA.
J Psychiatr Res. 2013 Aug;47(8):1101-9. doi: 10.1016/j.jpsychires.2013.03.021. Epub 2013 Apr 28.
Borderline personality disorder (BPD) often presents during adolescence. Early detection and intervention decreases its subsequent severity. However, little is known about early predictors and biological underpinnings of BPD. The observed abnormal functional connectivity among brain regions in BPD led to studies of white matter, as the neural substrate of connectivity. However, diffusion tensor imaging (DTI) studies in adult BPD have been inconclusive, and, as yet, there are no published DTI studies in borderline adolescents.
We conducted DTI tractography in 38 BPD patients (14-adolescents, 24-adults) and 32 healthy controls (13-adolescents, 19-adults).
We found bilateral tract-specific decreased fractional anisotropy (FA) in inferior longitudinal fasciculus (ILF) in BPD adolescents compared to adolescent controls. ILF FA was significantly higher in adolescent controls compared to BPD adolescents, BPD adults and adult controls (Wilks F(3,57) = 3.55, p < 0.02). Follow-up voxelwise TBSS analysis demonstrated lower FA in BPD adolescents compared to adolescent controls also in uncinate and occipitofrontal fasciculi.
FA generally develops along an inverted U-shape curve, increasing through adolescence, and slowly decreasing in adulthood. Our findings suggest that, in adolescent BPD, this normal developmental "peak" in FA, which is seen in healthy controls, is not achieved. This suggests a possible neural substrate for the previously reported OFC-amygdala disconnect in adults with BPD. It raises the possibility that a white matter tract abnormality in BPD present in adolescence may not be appreciable in adulthood, but a functional abnormality in the coordination among brain regions persists. Our finding represents a possible biological marker to identify those at risk for developing BPD.
边缘型人格障碍（BPD）常于青少年期起病。早期发现和干预可降低其后续严重程度。然而，对于 BPD 的早期预测因子和生物学基础知之甚少。BPD 患者大脑区域之间观察到的异常功能连接促使人们研究白质，即连接的神经基质。然而，成人 BPD 的弥散张量成像（DTI）研究尚无定论，且目前尚无 BPD 边缘型青少年的 DTI 研究。
我们对 38 例 BPD 患者（14 例青少年，24 例成人）和 32 例健康对照者（13 例青少年，19 例成人）进行了 DTI 束追踪。
我们发现与青少年对照组相比，BPD 青少年双侧下纵束（ILF）的分数各向异性（FA）降低。与 BPD 青少年、BPD 成人和成人对照组相比，青少年对照组的 ILF FA 显著更高（Wilks F(3,57) = 3.55，p < 0.02）。进一步的体素分析示，BPD 青少年的扣带束和额枕束 FA 也低于青少年对照组。
FA 通常沿倒 U 型曲线发展，在青少年期增加，然后在成年期缓慢下降。我们的发现表明，在青少年 BPD 中，健康对照组中可见的 FA 正常发育“高峰”并未出现。这表明 BPD 患者大脑前扣带回和杏仁核的连接中断可能存在潜在的神经生物学基础。这提示 BPD 患者在青少年期存在的白质束异常可能在成年期不明显，但大脑区域间的功能异常可能持续存在。我们的发现代表了一种可能的生物学标志物，可用于识别那些有发展为 BPD 风险的个体。
