Dementia Research Centre, Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, University College London, London, UK.
Research and Innovation Centre for Dementia-CRIDEM, University of Florence, Azienda Ospedaliera-Universitaria Careggi, Florence, Italy.
Eur J Neurol. 2024 Sep;31(9):e16370. doi: 10.1111/ene.16370. Epub 2024 Jun 21.
Dysphagia is an important feature of neurodegenerative diseases and potentially life-threatening in primary progressive aphasia (PPA) but remains poorly characterized in these syndromes. We hypothesized that dysphagia would be more prevalent in nonfluent/agrammatic variant (nfv)PPA than other PPA syndromes, predicted by accompanying motor features, and associated with atrophy affecting regions implicated in swallowing control.
In a retrospective case-control study at our tertiary referral centre, we recruited 56 patients with PPA (21 nfvPPA, 22 semantic variant [sv]PPA, 13 logopenic variant [lv]PPA). Using a pro forma based on caregiver surveys and clinical records, we documented dysphagia (present/absent) and associated, potentially predictive clinical, cognitive, and behavioural features. These were used to train a machine learning model. Patients' brain magnetic resonance imaging scans were assessed using voxel-based morphometry and region-of-interest analyses comparing differential atrophy profiles associated with dysphagia presence/absence.
Dysphagia was significantly more prevalent in nfvPPA (43% vs. 5% svPPA and no lvPPA). The machine learning model revealed a hierarchy of features predicting dysphagia in the nfvPPA group, with excellent classification accuracy (90.5%, 95% confidence interval = 77.9-100); the strongest predictor was orofacial apraxia, followed by older age, parkinsonism, more severe behavioural disturbance, and more severe cognitive impairment. Significant grey matter atrophy correlates of dysphagia in nfvPPA were identified in left middle frontal, right superior frontal, and right supramarginal gyri and right caudate.
Dysphagia is a common feature of nfvPPA, linked to underlying corticosubcortical network dysfunction. Clinicians should anticipate this symptom particularly in the context of other motor features and more severe disease.
吞咽困难是神经退行性疾病的一个重要特征，在原发性进行性失语症（PPA）中可能具有生命威胁，但在这些综合征中仍未得到充分描述。我们假设，吞咽困难在非流利/语法障碍变异型（nfv）PPA 中比其他 PPA 综合征更为常见，这可以通过伴随的运动特征来预测，并与影响吞咽控制相关区域的萎缩有关。
在我们的三级转诊中心进行的一项回顾性病例对照研究中，我们招募了 56 名 PPA 患者（21 名 nfvPPA、22 名语义变异型[sv]PPA、13 名失语法变异型[lv]PPA）。我们使用基于护理人员调查和临床记录的表格，记录了吞咽困难（存在/不存在）和相关的、可能具有预测性的临床、认知和行为特征。这些特征被用于训练机器学习模型。使用基于体素的形态测量法和感兴趣区域分析，对患者的脑磁共振成像扫描进行评估，比较与吞咽困难存在/不存在相关的差异萎缩图谱。
吞咽困难在 nfvPPA 中更为常见（43% vs. 5% svPPA 无 lvPPA）。机器学习模型显示，nfvPPA 组中存在预测吞咽困难的特征层次结构，分类准确率非常高（90.5%，95%置信区间=77.9-100）；最强的预测因子是口颜面失用症，其次是年龄较大、帕金森病、更严重的行为障碍和更严重的认知障碍。在 nfvPPA 中，吞咽困难的显著灰质萎缩相关区域位于左侧额中回、右侧额上回和右侧缘上回以及右侧尾状核。
吞咽困难是 nfvPPA 的常见特征，与皮质下网络功能障碍有关。临床医生应特别在存在其他运动特征和更严重疾病的情况下预测到这种症状。
