Busby Natalie, Rangus Ida, Riccardi Nicholas, Newman-Norlund Roger, Rorden Chris, Fridriksson Julius, Bonilha Leonardo
Department of Communication Sciences and Disorders, University of South Carolina, Columbia, SC, USA.
Department of Psychology, University of South Carolina, Columbia, SC, USA.
Aging Brain. 2025 Aug 21;8:100150. doi: 10.1016/j.nbas.2025.100150. eCollection 2025.
There is evidence that overall physical health in general and cardiovascular risk (CV) factors in particular are associated with structural brain changes and recovery trajectories in stroke aphasia, however the nature of these relationships is still unclear. Therefore, we investigated the mediating role of advanced brain aging on the relationship between cardiovascular health and aphasia severity in chronic stroke.
Participants (N = 95) with chronic stroke aphasia completed behavioral testing including the Western Aphasia Battery Aphasia Quotient (WAB AQ) and MRI scanning. Brain age of each participant was calculated using BrainAgeR and their proportional brain age (PBA) was calculated through the relative difference between estimated brain age and chronological age. A CV risk score was also calculated for each participant using the Framingham Heart Study General Cardiovascular Disease Risk Prediction Using BMI calculator. To determine if the relationship between vascular score and WAB AQ is related to brain age, we performed a statistical mediation analysis where the independent variable was vascular score, the dependent variable was WAB AQ and the mediating variable was PBA.
Individuals with chronic stroke aphasia who had more cardiovascular risk factors (i.e., a higher vascular score), typically had worse aphasia severity (lower WAB AQ) and advanced brain aging (increased PBA). An increased PBA was also associated with worse aphasia severity. Mediation analyses revealed that individuals with a higher vascular score (i.e., worse heart health) typically had advanced brain aging and, in turn, advanced brain aging was associated with worse aphasia severity. Therefore, the total effect of cardiovascular health on aphasia severity is partially explained by the indirect effects of advanced brain aging.
Our results corroborate the previous findings suggesting that physical health is an important factor for both brain structural integrity and recovery in stroke aphasia and extends this by demonstrating the mediating effect of advanced brain aging on the relationship between cardiovascular health and aphasia severity. These results highlight the importance of maintaining physical health alongside aphasia therapy and may be an important factor to consider in the long-term management of chronic stroke. Ensuring that individuals have access to resources needed for proper exercise and maintaining a balanced diet may help to improve overall brain structural integrity and therefore may impact aphasia severity.
有证据表明，总体身体健康状况，尤其是心血管风险（CV）因素，与中风失语症患者的脑结构变化及恢复轨迹相关，然而这些关系的本质仍不清楚。因此，我们研究了脑高级老化在慢性中风患者心血管健康与失语严重程度之间关系中的中介作用。
患有慢性中风失语症的参与者（N = 95）完成了包括西方失语症成套测验失语商数（WAB AQ）在内的行为测试以及MRI扫描。使用BrainAgeR计算每位参与者的脑龄，并通过估计脑龄与实际年龄之间的相对差异计算其比例脑龄（PBA）。还使用弗雷明汉心脏研究基于BMI的一般心血管疾病风险预测计算器为每位参与者计算心血管风险评分。为了确定血管评分与WAB AQ之间的关系是否与脑龄有关，我们进行了一项统计中介分析，其中自变量是血管评分，因变量是WAB AQ，中介变量是PBA。
患有慢性中风失语症且心血管风险因素较多（即血管评分较高）的个体，通常失语严重程度更差（WAB AQ较低）且脑高级老化程度较高（PBA增加）。PBA增加也与更差的失语严重程度相关。中介分析表明，血管评分较高（即心脏健康状况较差）的个体通常脑高级老化程度较高，而反过来，脑高级老化程度较高与更差的失语严重程度相关。因此，心血管健康对失语严重程度的总体影响部分可由脑高级老化的间接影响来解释。
我们的结果证实了先前的研究发现，即身体健康是中风失语症患者脑结构完整性和恢复的重要因素，并通过证明脑高级老化在心血管健康与失语严重程度之间关系中的中介作用扩展了这一发现。这些结果突出了在失语症治疗的同时保持身体健康的重要性，并且可能是慢性中风长期管理中需要考虑的一个重要因素。确保个体能够获得适当运动和保持均衡饮食所需的资源，可能有助于改善整体脑结构完整性，从而可能影响失语严重程度。
