Supplementary Material for: Differential Progression of Dysphagia in Heredity and Sporadic Ataxias Involving Multiple Systems

Sporadic ataxia affecting multiple systems, such as cerebellar, extrapyramidal, and autonomic systems, is known as multiple system atrophy cerebellar type (MSA-C), while similar multisystem involvements are seen in certain types of hereditary ataxia, such as spinocerebellar ataxia type 3 (SCA3). Dysphagia is a common symptom that can predispose to aspiration pneumonia, a major cause of death in patients with these diseases. Although the progressions of dysphagia in patients with MSA-C have been reported sporadically, those in SCA3 have not been reported. We retrospectively compared the results of repetitive videofluoroscopic examinations in patients with SCA3 (n = 6) and in those with MSA-C (n = 7). The result showed that the gross progression of dysphagia was significantly slower in patients with SCA3 than in those with MSA-C, but the maximum progression speeds were not significantly different. The dysphagia severities were not associated with impaired activity of daily living evaluated by the Barthel index in MSA-C, but were associated in SCA3. Despite the small number of patients enrolled, these data suggest that physicians should monitor swallowing functions in patients with SCA3 after mild dysphagia develops because it may progress as rapidly as it does in MSA-C.

累及小脑、锥体外系及自主神经系统等多系统的散发性共济失调，被称为多系统萎缩小脑型（multiple system atrophy cerebellar type, MSA-C）；而部分遗传性共济失调亚型亦可出现类似的多系统受累表现，例如3型脊髓小脑共济失调（spinocerebellar ataxia type 3, SCA3）。吞咽困难（dysphagia）是这类疾病患者的常见症状，可增加吸入性肺炎（aspiration pneumonia）的发病风险，而后者是这类患者的主要死亡原因。尽管目前已有零星报道多系统萎缩小脑型患者的吞咽困难病情进展，但3型脊髓小脑共济失调患者的吞咽困难进展情况尚未见相关文献报道。本研究回顾性对比了6例3型脊髓小脑共济失调患者与7例多系统萎缩小脑型患者的多次视频透视吞咽检查（videofluoroscopic examinations）结果。结果显示，3型脊髓小脑共济失调患者的吞咽困难总体进展速度显著慢于多系统萎缩小脑型患者，但二者的最大进展速度并无显著差异。在多系统萎缩小脑型患者中，吞咽困难严重程度与经巴氏指数（Barthel index）评估的日常活动能力受损程度无相关性，但在3型脊髓小脑共济失调患者中二者存在显著相关性。尽管本研究纳入的患者样本量较小，但上述数据提示临床医师应在3型脊髓小脑共济失调患者出现轻度吞咽困难后对其吞咽功能进行监测，因为此类患者的吞咽困难进展速度可能与多系统萎缩小脑型患者同样迅速。