We examined associations of distant histories of mild traumatic brain injury (mTBI) with non-linear and linear trajectories of white matter (WM) properties across a wide age range (23–77). Diffusion tensor imaging (DTI) data obtained from 171 Veterans with histories of clinically diagnosed mTBIs and 115 controls were subjected to tractography, isolating 20 major WM tracts. Non-linear and linear effects of age on each tract's diffusion properties were examined in terms of their interactions with group (mTBI and control). The non-linear model revealed 7 tracts in which the mTBI group's DTI metrics rapidly deviated from control trajectories in middle and late adulthoods, despite the injuries having occurred in the late 20s, on average. In contrast, no interactions between prior injuries and age were detected when examining linear trajectories. Distant mTBIs may thus accelerate normal age-related trajectories of WM degeneration much later in life. As such, life-long histories of head trauma should be assessed in all patients in their mid-to-late adulthoods, whether neurologically healthy or presenting with seemingly unrelated neuropathology.

我们检查了远距离轻度创伤性脑损伤 (mTBI) 病史与广泛年龄范围内的白质 (WM) 特性的非线性和线性轨迹之间的关联 (23-77)。对 171 名有临床诊断为 mTBI 病史的退伍军人和 115 名对照者获得的扩散张量成像 (DTI) 数据进行了纤维束成像，分离出 20 个主要的 WM 束。根据它们与组（mTBI 和对照）的相互作用，检查了年龄对每个区域的扩散特性的非线性和线性影响。非线性模型揭示了 7 个区域，其中 mTBI 组的 DTI 指标在成年中期和晚期迅速偏离控制轨迹，尽管平均而言，伤害发生在 20 年代后期。相比之下，在检查线性轨迹时，没有检测到先前受伤和年龄之间的相互作用。因此，远处的 mTBI 可能会在生命后期加速 WM 退化的正常年龄相关轨迹。因此，无论是神经健康还是看似无关的神经病理学，都应在所有中晚期的患者中评估头部外伤的终生病史。