1 VA RR&D National Center for the Medical Consequences of SCI, James J. Peters VAMC, Bronx, New York.
2 Department of Medicine, The Icahn School of Medicine, Mount Sinai, New York, New York.
J Neurotrauma. 2018 Dec 15;35(24):2957-2964. doi: 10.1089/neu.2018.5760. Epub 2018 Oct 3.
Cognitive deficits are prevalent in the spinal cord injury (SCI) population, and consensus suggests that concomitant traumatic brain injury or comorbid conditions are primarily responsible for these deficits. However, mounting evidence supports the possibility that systemic and cerebral hemodynamic dysfunction may contribute to the cognitive deficits reported in persons with SCI. We sought to determine the contribution of changes in blood pressure (BP) and changes in cerebral blood flow velocity (CBFv) to test performance on the Symbol Digit Modalities Test (SDMT) in persons with SCI compared with matched non-SCI controls. Participants included 36 non-SCI controls and 67 persons with SCI: 33 with paraplegia (T2-T12) and 34 with tetraplegia (C3-T1). Continuous beat-to-beat BP and simultaneous CBFv was monitored for 5 min during seated rest and during the SDMT, which assesses information processing speed, sustained attention, and visual working memory. The results indicate significantly lower SDMT scores in the group with tetraplegia (44 ± 10) compared to the non-SCI controls (53 ± 14; p < 0.01); however, SDMT scores did not differ significantly between the non-SCI controls and the group with paraplegia (49 ± 13). Whereas group affiliation was the most significant predictor of test performance (F = 4.84; p = 0.010, η = 0.088), change in systolic BP (SBP) (r = 0.047, p = 0.028) and change in diastolic CBFv (DFV) (r = 0.047, p = 0.028) contributed significantly to SDMT scores. Further, change in SBP accounted for a significant amount of variance in change in DFV in the total study sample (r = 0.090; p = 0.002). These results support previous findings of cognitive deficits in persons with SCI and indicate that inadequate systemic and cerebral hemodynamic responses to testing contribute to test performance. Therefore, clinical treatment of cognitive dysfunction in the SCI population should consider focusing on increasing systemic BP to improve CBFv, particularly in individuals with lesions above T1.
认知缺陷在脊髓损伤（SCI）人群中很常见，共识认为，同时发生的创伤性脑损伤或合并症是这些缺陷的主要原因。然而，越来越多的证据支持这样一种可能性，即全身和脑血流动力学功能障碍可能导致 SCI 患者报告的认知缺陷。我们试图确定血压（BP）变化和脑血流速度（CBFv）变化对 SCI 患者与匹配的非 SCI 对照组在符号数字模态测试（SDMT）上的测试表现的贡献。参与者包括 36 名非 SCI 对照组和 67 名 SCI 患者：33 名截瘫（T2-T12）和 34 名四肢瘫（C3-T1）。在坐姿休息和 SDMT 期间，连续监测了 5 分钟的有节奏的 BP 和同时的 CBFv，SDMT 评估信息处理速度、持续注意力和视觉工作记忆。结果表明，四肢瘫组的 SDMT 评分明显较低（44±10），而非 SCI 对照组的评分较高（53±14；p<0.01）；然而，非 SCI 对照组和截瘫组之间的 SDMT 评分没有显著差异（49±13）。尽管组隶属关系是测试表现的最显著预测因素（F=4.84；p=0.010，η=0.088），收缩压（SBP）变化（r=0.047，p=0.028）和舒张期 CBFv 变化（DFV）（r=0.047，p=0.028）对 SDMT 评分有显著贡献。此外，在整个研究样本中，SBP 变化解释了 DFV 变化的大量方差（r=0.090；p=0.002）。这些结果支持之前关于 SCI 患者认知缺陷的发现，并表明对测试的全身和脑血流动力学反应不足会影响测试表现。因此，对 SCI 人群认知功能障碍的临床治疗应考虑重点提高全身血压以改善 CBFv，特别是在 T1 以上有病变的个体。
