Answers are grounded in this paper and cite their sources.
The symptoms of SD begin gradually and worsen over time. New evidence indicates that SD symptoms may continue to progress without plateau in at least a subset of patients. Individuals with SD and coexisting vocal tremor experience symptom trajectories similar to those of patients with SD only. Although Botox may attenuate voice symptoms, these effects do not appear to be strongly related to the V-RQOL scores. These results provide new and valuable insights regarding the onset, course, progression, and treatment of SD.
No takes yet. Share an insight, caveat, or question.
Tanner et al. (2011) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: