Defining differences in patient characteristics between spasmodic dysphonia and laryngeal tremor

Abstract

Objective To compare presenting characteristics of patients with adductor spasmodic dysphonia (ADSD), ADSD with laryngeal tremor (ADSD + LT), and laryngeal tremor without ADSD (LT) Design Cross-sectional analysis Methods Patients treated for laryngeal movement disorders (1990–2016) were included. ANOVA and Chi square tests measured differences in patient characteristics across the three disease groups. Using ADSD as the referent, multivariable logistic regression models were used to determine whether potential risk factors including patient demographics, family history, presence of potential inciting events prior to disease onset, and co-prevalent movement disorders were associated with ADSD+LT or LT. Results In all, 652 patients with ADSD (n=377), ADSD + LT (n=98), and LT (n=177) were included. ADSD patients were significantly younger than those with ADSD + LT and LT (52.5±13.4, 63.9±11.3, and 69.3±10.5 years, respectively; p<0.001). Co-prevalent movement disorders were more common in ADSD + LT (38.7%) and LT (57.1%) groups than in the ADSD group (11.5%; p<0.001). Compared to ADSD, patients with ADSD + LT and LT were more likely to develop an additional movement disorder during follow-up. In multivariable analyses, increasing age, female gender, and having a movement disorder at presentation were associated with significantly greater odds of having ADSD + LT or LT when compared to ADSD. Conclusion ADSD + LT patients demonstrate intermediate gender composition and age distributions between those with ADSD and LT. These findings suggest that ADSD + LT may be a distinct phenotype in the spectrum of laryngeal movement disorders.

How can we make better decisions about dystonic voice management?

“…The age of diagnosis for those patients with spasmodic dysphonia/vocal tremor is between that observed for spasmodic dysphonia and that of vocal tremor [28]. When examined clinically, the vocal tremor of patients with spasmodic dysphonia becomes audibly apparent when the patients are asked to hold a sustained vowel.…”

Neural Representations of the Voice Tremor Spectrum

“…Clinically, both similarities and differences between patients with ETv and DTv have been described. DTv, in combination with LD, shows intermediate age and sex distributions between ETv and LD without tremor 5 . Botulinum toxin injections yield a better therapeutic response in LD without tremor, intermediate in DTv, and worse in ETv 6‐8 .…”

“…DTv, in combination with LD, shows intermediate age and sex distributions between ETv and LD without tremor. 5 Botulinum toxin injections yield a better therapeutic response in LD without tremor, intermediate in DTv, and worse in ETv. [6][7][8] In contrast, alcohol is more beneficial for symptom improvement in ETv, followed by DTv and LD without tremor.…”