Exploring Autonomic Dysfunction in Functional Dysphonia: a Pilot Study

Background. Although psychological factors have been implicated in patients with functional dysphonia (FD), conventional voice therapy (CVT) typically targets the aberrant voice symptoms exclusively. Yet, CVT is not always successful, and in view of the significant adverse quality of life impact combined with the financial burden on the healthcare system, research is needed to elucidate the underlying psychophysiology of FD and improve treatment outcomes.

Objectives. The first objective of this pilot study is to investigate the occurrence and frequency of symptoms and/or disorders related to autonomic nervous system (ANS) dysfunction in patients with FD. The second objective is to investigate the effects of a therapy based on ANS regulation, i.e. heart rate variability (HRV) biofeedback, in this population.

Methods. Autonomic (dys)function will be investigated using both physiological measures (e.g. HRV) and psychological patient-reported outcome measures (e.g. Depression Anxiety and Stress Scale). Patients will receive 1 month of HRV biofeedback training with 20min of daily practice. Both the autonomic assessment and the voice assessment will be performed pretherapy, posttherapy and at 3 months follow-up.

Results. Data collection for this pilot study is currently ongoing and the first results will be available by the time of the symposium. In a later stage of the project, autonomic dysfunction in FD will be compared with gender- and age-matched vocally healthy controls, using a case-control study. Second, the effects of the ANS regulation therapy in FD will be compared with CVT alone or in combination with ANS regulation therapy, using a randomized controlled trial.