Spinocerebellar ataxia type 6 (SCA6) is characterized by adult-onset, slowly progressive cerebellar ataxia. Initial symptoms are gait unsteadiness, stumbling, and imbalance. Problems with swallowing and choking are common.
Problems with swallowing (dysphagia) are generally milder in SCA6 patients than in other ataxias like SCA3.
To determine the abnormalities in the pharyngeal phase in fourteen SCA6 patients, swallow exams (videofluoroscopic examinations) were repeatedly performed. A video fluoroscopic swallowing exam uses a form of real-time x-ray called fluoroscopy to evaluate a patient’s ability to swallow safely and effectively.
The results showed that the gross progression of dysphagia was apparently slow.
But four patients had progressive dysphagia at an early disease stage; dysphagia began within 10 years from the onset of ataxia and rapidly progressed.
A common clinical feature of the four patients was a significantly older age at the onset of ataxia (74 years old), associated with significantly shorter DNA extension. The other patients experienced their first symptoms at the age of 60.
This finding surprisingly indicated that patients who had shorter repeats (DNA extension) and thereby later onset and potentially better prognoses were at risk for dysphagia-associated problems.
Isono, C., Hirano, M., Sakamoto, H. et al. Dysphagia (2017). doi:10.1007/s00455-016-9771-1