The presence of dysphagia in patients with cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS): a subjective and objective study

Purpose The aim of this study was to determine the prevalence of dysphagia in patients with cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS), characterizing this condition, both in its objective dimension and in terms of quality of life (QoL). Methods A cross-sectional study was developed in 11 patients diagnosed of CANVAS. In all patients, clinical records were reviewed and the Eating assessment tool 10 (EAT-10) was performed as screening of oropharyngeal dysphagia. To evaluate the QoL impairment secondary to dysphagia, we applied the swallowing quality of life questionnaire (SWAL-QOL) and the MD Anderson Dysphagia Inventory (MDADI). To evaluate the deglutition mechanisms impaired, two objective-instrumental studies were performed: the volume-viscosity swallow test (V-VST) and the fiberoptic endoscopic evaluation of swallowing (FEES). Results 82% of the patients presented an abnormal EAT-10 score. A correlation was found between the EAT-10 and MDADI and between both QoL questionnaires. After the FEES and V-VST analysis, all 11 patients presented some degree of swallow effectiveness impairment, and most of them safety alterations as well. Conclusion CANVAS remains an underestimated and underdiagnosed condition and the prevalence of swallowing disorders in those patients is higher than expected. Despite the possibility that EAT-10 works as a useful screening test to predict the results in the QoL questionnaires, the absence of correlation between QoL test and instrumental results suggests that to properly evaluate the patients swallowing status, objective instrumental procedures must be conducted.