Treatment effectiveness for Vocal Cord Dysfunction in adults and adolescents: A systematic review

Abstract

Objective: To determine whether treatment effectiveness can be established for a range of vocal cord dysfunction (VCD) interventions in adolescents and adults.Design: A systematic review of the literature and risk of bias appraisal was completed using the Joanna Briggs Institute Critical Appraisal Tools. Data were qualitatively synthesized in the broad intervention groups of glottic airway and respiratory retraining, pharmacological therapies, airway device therapies and psychological therapies.Data sources: Nine electronic databases, two clinical trial registries and the grey literature were searched from inception to September 2021 for articles on VCD interventions or equivalent terms.Eligibility criteria: Studies were included if they were randomized controlled trials, non-randomized controlled trials, quasi-experimental pre-and post-test studies and within-subject repeated measure designs, participants were 13 years or older, VCD was diagnosed using laryngoscopy or CT larynx, VCD intervention was provided and outcome measures reported on VCD symptoms. Results:The search yielded no randomized controlled trials. There were 17 quasiexperimental studies that met the eligibility criteria, and these studies reported on glottic airway and respiratory retraining, botulinum toxin injections, inspiratory muscle strength training and amitriptyline; all were associated with VCD symptom reduction. In addition, 2 within-subject repeated measure studies reported inspiratory muscle strength training and respiratory retraining to be effective in reducing symptoms in participants with exertional VCD. The included studies were reported in fulltext publications (11) and conference proceedings (8). There was a high risk of bias and low quality of evidence across all intervention areas. Conclusion: Glottic airway and respiratory retraining, botulinum toxin injections, lowdose amitriptyline and inspiratory muscle strength training devices have been associated with symptom reduction in adults and adolescents with vocal cord dysfunction. Limited objective data exist to support the effectiveness of these interventions, and robust controlled trials are needed in this area.

Systematic review of the effectiveness of non-pharmacological interventions used to treat adults with inducible laryngeal obstruction

“…However, although Patel et al ’s systematic review highlights preliminary support for SLT as an effective ILO treatment it concludes the evidence supporting efficacy is in its infancy 19. Similarly, Mahoney et al ’s recent work to determine treatment effectiveness for a range of vocal cord dysfunction interventions (pharmacological and non-pharmacological) concluded limited objective data exists to support the effectiveness of these interventions 20…”

“…It is unknown if all components of the intervention are essential or if it is acceptable to patients. Further, other non-pharmacological interventions are reported beneficial, for example, airway device techniques 20 22 23…”

“… 19 Similarly, Mahoney et al ’s recent work to determine treatment effectiveness for a range of vocal cord dysfunction interventions (pharmacological and non-pharmacological) concluded limited objective data exists to support the effectiveness of these interventions. 20 …”

“…Further, other non-pharmacological interventions are reported beneficial, for example, airway device techniques. 20 22 23 …”

Lone Ranger or Handpicked Posse? How Multidisciplinary Assessment Helps Evaluate Suspected Laryngeal Disorders

“…This area needs further work, because a recent systematic review has not shown high-quality evidence for any effective treatments for VCD. 13 Third, systematic assessment also helped clinicians forge effective collaborations with their patients. Videos of laryngoscopy findings were used to educate patients regarding their laryngeal disorders to promote their understanding and subsequent adherence to interventions.…”