Evaluating the efficacy of voice therapy for functional, organic and neurological voice disorders

A Comparison of Voice and Psychotherapeutic Treatments for Adults With Functional Voice Disorders: A Systematic Review

OBJECTIVE

To examine the effect of traditional voice therapy and cognitive therapy on the voice and client-wellbeing outcomes in adults with functional voice disorders (FVD).

METHODS

A systematic review of English articles was conducted using Medline (Ovid), Embase (Elsevier), CINAHL (Ebsco), The Cochrane Central Register of Controlled Trials (CENTRAL), PsychInfo (Ebsco) and Speechbite from inception to current date. Additional studies were identified through bibliographies and authors were contacted when further information was required from an article. All study designs were included with pretest/posttest outcome measures related to voice. Independent extraction of studies was completed by three authors using predefined data fields and quality assessment tools.

RESULTS

Outcomes of 23 studies (2 RCTs and 21 cohort or case studies) are summarised using a narrative style due to heterogeneity of interventions and outcome scales used. Overall research quality of included studies was low, with many cohort and case studies lacking controls, blinding and robust outcome measures.

CONCLUSIONS

There are some benefits to pairing cognitive behavioural therapy (CBT) with traditional voice therapy for FVD including improved voice quality, psychosocial wellbeing and prevention of relapse. It is feasible to train speech-language pathologists (SLPs) in CBT-enhanced voice therapy. Further high-quality research is needed, however, to guide the clinical implementation of CBT for the management of FVD.

Pre and Post-operative Voice Therapy Intervention for Benign Vocal Fold Lesions: A Systematic Review

Benign vocal fold lesions cause dysphonia by preventing vocal fold closure, causing irregular vibration and increasing compensatory muscle tension. Voice therapy delivered in addition to phonosurgery may improve voice and quality of life outcomes but the evidence base is lacking and what constitutes voice therapy for this population is not defined. The purpose of this systematic review is to critically evaluate the evidence for pre and post-operative voice therapy to inform the development of an evidence based intervention.

STUDY DESIGN

Systematic Review.

METHODS

Electronic databases were searched using key terms including dysphonia, phonosurgery, voice therapy and outcomes. Eligible articles were extracted and reviewed by the authors for risk of bias and for information regarding the content, timing and intensity of any pre and post-operative voice therapy intervention.

RESULTS

Of the 432 articles identified, 35 met the inclusion criteria and were included in the review. 5 were RCTs, 2 were individual cohort studies, 1 was a case control study and 26 were case series. There was considerable heterogeneity in participant characteristics. Information was frequently lacking regarding the content timing and intensity of the reported voice therapy intervention, and where present, interventions were highly variable.

CONCLUSION

Reporting in relevant literature is limited in all aspects of content, timing and intensity of intervention. Further intervention development work is required to develop a robust voice therapy treatment intervention for this population, before effectiveness work can commence.

Functional Speech and Voice Disorders: Approaches to Diagnosis and Treatment

Historically, formal training for speech-language therapists (SLTs) in the area of functional speech and voice disorders (FSVD) has been limited, as has the body of empirical research in this content area. Recent efforts in the field have codified expert opinions on best practices for diagnosing and treating FSVD and have begun to demonstrate positive treatment outcomes. To provide comprehensive interventions for these complex conditions at the intersection of neurology, psychiatry, and other medical specialties, the SLT must not only build knowledge of diagnostic strategies and components of symptomatic treatment in FSVD but also embrace behavior change techniques and counseling strategies.

Working Together to Find a Voice: Recommendations for Voice Healthcare Based on Expert-By-Experience and Practitioner Consensus

OBJECTIVES

Voice care services aim to provide effective and meaningful voice care. Current practice guidance recommends a multidisciplinary voice care approach, supported by the evidence-base and practitioner experience. However, unlike other areas of physical and mental health, current voice care guidance does not explicitly include the voices of experts-by-experience, meaning those who have lived experience of voice difficulties. The perspectives of those working within nonclinical voice professions, such as vocal coaches, are also often omitted. There is therefore a need for updated practice guidance which prioritizes expert-by-experience and nonclinical perspectives.

METHODS

Vocal Health Education hosted a consensus meeting in London, UK. The meeting was coproduced with experts-by-experience, and attendees included those with lived experience of voice difficulties and practitioners across a range of disciplines within voice care. The content of the meeting was synthesized into themes and associated recommendations were drafted and agreed to by all attendees.

RESULTS

The consensus statement offers practical advice to those working in voice care. Recommendations are offered for multidisciplinary and biopsychosocial voice care, with a focus on person-centered practice and the valuing of lived experience. Through discussion, consensus was reached regarding recommendations for voice care assessment and treatment, practitioner approach, psychosocial considerations, and service design. The need for greater expert-by-experience involvement, coproduction, and co-construction was emphasized throughout.

CONCLUSIONS

This report emphasizes the voices of those with lived experience. It highlights ways of updating or improving current care, with the aim of informing clinical practice as well as research and service development. The consensus statement is the first in voice care to include experts-by-experience at the center of its recommendations, underlining the need for more coproduced and co-constructed research and practice within voice healthcare.

Laryngeal dysfunction is prominent in asthmatic women treated by inhaled corticosteroids

BACKGROUND

Dysphonia is a frequent comorbidity of asthma and has been suggested to be a local side effect of inhaled corticosteroids due to laryngeal candidiasis. We hypothesized that dysphonia in asthmatics was not due to laryngeal organic lesions but to laryngeal dysfunction during phonation (LDP).

OBJECTIVE

We compared the frequency of LDP in female asthmatic patients treated with inhaled corticosteroids to female controls.

METHODS

We compared 68 asthmatic female patients to 53 female control subjects. Pulmonary function tests were performed and the asthmatic patients classified according to the level of inhaled corticosteroids. Dysphonia was defined as a Vocal Handicap Index ≥18 or GRBAS score ≥2. All patients underwent video laryngo-strobe examination, analyzed blindly and separately by two otolaryngologists, describing mucosal changes, LDP, or Organic lesions linked to Laryngeal Dysfunction during Phonation (OLDP).

RESULTS

66.2% of the asthmatic patients exhibited dysphonia and 11.3% of controls (p < 0.001). No laryngeal candidiasis was found, only 3 patients presented laryngeal mucosa inflammation. LDP was observed in 60.3% of asthmatic patients and 18.9% of controls (p < 0.001), and no difference was found for OLDP (11.8% vs. 13.2%). No association was made between LDP, the dosage of inhaled corticosteroid, and bronchial obstruction.

CONCLUSIONS

Asthmatic patients were more dysphonic than control subjects. This phenomenon was not explained by mucosal inflammation, laryngeal candidiasis or OLDP. Asthmatic patients had more LDP than controls. There was no relation between LDP, inhaled corticosteroids dosage or bronchial obstruction. These results change our view of inhaled corticosteroid side effects in female asthmatic patients.

Interactions Between Breathy and Rough Voice Qualities and Their Contributions to Overall Dysphonia Severity

PURPOSE

Dysphonic voices typically present multiple voice quality dimensions. This study investigated potential interactions between perceived breathiness and roughness and their contributions to overall dysphonia severity.

METHOD

Synthetic stimuli based on four talkers were created to systematically map out potential interactions. For each talker, a stimulus matrix composed of 49 stimuli (seven breathiness steps × seven roughness steps) was created by varying aspiration noise and open quotient to manipulate breathiness and superimposing amplitude modulation of varying depths to simulate roughness. One-dimensional matching (1DMA) and magnitude estimation (1DME) tasks were used to measure perceived breathiness, roughness, their potential interactions, and overall dysphonia severity. Additional 1DME tasks were used to assess a set of natural stimuli that varied along both breathiness and roughness.

RESULTS

For the synthetic stimuli, the 1DMA task indicated little interaction between the two voice qualities. For the 1DME task, breathiness magnitude was influenced by roughness step to a greater extent than roughness magnitude was influenced by breathiness step. The additive contributions of breathiness and roughness to overall severity gradually diminished with increasing breathiness and roughness steps, possibly reflecting a ceiling effect in the 1DME task. For the natural stimuli, little consistent interaction was observed between breathiness and roughness.

CONCLUSIONS

The matching task revealed minimal interaction between perceived breathiness and roughness, whereas the magnitude estimation task revealed some interaction between the two qualities and their cumulative contributions to overall dysphonia severity. Task differences are discussed in terms of differences in response bias and the role of perceptual anchors.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21313701.

A Randomized Controlled Trial With Female Teachers: Are there Differences Between and Within the Outcomes in Voice Therapy Groups With and Without Carryover Strategies?

PURPOSE

We investigated if outcomes differ between voice therapy groups systematically using carryover strategies (attempts to generalize new vocal skills outside the clinic) and voice therapy with no emphasis on any generalizing process (here referred to as traditional voice therapy).

METHOD

A randomized controlled trial was conducted. Participants (53 female teachers with voice disorders) were randomly allocated into three groups: Carryover (a group receiving voice therapy using carryover strategies), Trad (a group receiving voice therapy with no emphasis on any generalizing process), Controls (a group on an eight-week non-therapy period). Prior to the trial a direct laryngoscopy was performed with a videolaryngostroboscopy system and/or nasofaryngofiberoscope with stroboscopy. Before and after therapy and at follow-up a voice evaluation protocol was implemented consisting of subjective assessments (Questionnaire on Voice Symptoms, and the Voice Activity and Participation Profile; VAPP), and objective measurements (voice sample recordings, acoustic analysis [SPL, sound pressure level; f0, fundamental frequency; alpha-ratio, tilt of the sound spectrum slope]).

RESULTS

No differences were found between the groups. Several significant changes occurred within the groups between initial phase vs. post-therapy and initial phase vs. follow-up. In the Carryover group text reading the alpha-ratio became lower (P = 0.011) and spontaneous speech f0 increased (P = 0.024) after the therapy and [a:] SPL increased (P = 0.042) at follow-up. In the Trad group post-therapy [a:] alpha-ratio became lower (P = 0.012) and spontaneous speech f0 decreased (P = 0.034). After therapy VAPP scores showed improvement in voice-related quality of life in both therapy groups (Carryover P = 0.003; Trad P = 0.01) but only in Carryover at follow-up (P = 0.000). Voice symptoms decreased in the Carryover group post-therapy (P = 0.001) and at follow-up (P = 0.000) and after Controls' eight-week non-therapy period (P = 0.003).

CONCLUSION

The results showed that carryover strategies give no additional advantages in voice therapy. However, the decreasing trend in the Carryover group's voice complaints at follow-up would suggest that carryover strategies may have long-lasting effects. The results also confirm that voice therapy is efficient in improving voice-related quality of life.

Cricothyroid Muscle Botulinum Toxin Chemodenervation to Treat Recalcitrant High-Pitched Functional Dysphonia in an Adult Male

INTRODUCTION

Functional dysphonia occurs in the absence of structural or neurologic laryngeal abnormalities with various manifestations including aphonia and inappropriate vocal pitch. Voice therapy is the first-line treatment, and literature on treatment options for functional dysphonia unresponsive to voice therapy is limited.

METHODS

Retrospective medical records review and report of a case.

RESULTS

We report a unique case of an adult male with recalcitrant high-pitched functional dysphonia of adult-onset that was successfully treated with a single cricothyroid muscle botulinum toxin (Botox) chemodenervation injection.

CONCLUSION

Cricothyroid muscle botulinum toxin chemodenervation can be an effective treatment for recalcitrant functional dysphonia.

Management of functional communication, swallowing, cough and related disorders: consensus recommendations for speech and language therapy

Communication problems (eg, dysphonia, dysfluency and language and articulation disorders), swallowing disorders (dysphagia and globus), cough and upper airway symptoms, resulting from functional neurological disorder (FND), are commonly encountered by speech and language professionals. However, there are few descriptions in the literature of the most effective practical management approaches. This consensus document aims to provide recommendations for assessment and intervention that are relevant to both adults and young people. An international panel of speech and language professionals with expertise in FND were approached to take part. Participants responded individually by email to a set of key questions regarding best practice for assessment and interventions. Next, a video conference was held in which participants discussed and debated the answers to these key questions, aiming to achieve consensus on each issue. Drafts of the collated consensus recommendations were circulated until consensus was achieved. FND should be diagnosed on the basis of positive clinical features. Speech and language therapy for FND should address illness beliefs, self-directed attention and abnormal movement patterns through a process of education, symptomatic treatment and cognitive behavioural therapy within a supportive therapeutic environment. We provide specific examples of these strategies for different symptoms. Speech and language professionals have a key role in the management of people with communication and related symptoms of FND. It is intended that these expert recommendations serve as both a practical toolkit and a starting point for further research into evidence-based treatments.

Effectiveness of Intensive Voice Therapy Versus Weekly Therapy for Muscle Tension Dysphonia: A Noninferiority Randomised Controlled Trial With Nested Focus Group

OBJECTIVES

To investigate the noninferiority of intensive voice therapy and compare its effects with weekly voice therapy on multidimensional outcomes of voice and well-being, satisfaction, and attendance in people with muscle tension dysphonia (MTD). The study further aimed to explore clinician's perceptions of barriers and enablers to implementation of intensive therapy.

STUDY DESIGN

Noninferiority randomised controlled trial with nested focus group.

METHODS

Twenty adults with MTD were randomised to receive either weekly voice therapy (1 hour per week for 8 weeks) or intensive voice therapy (1 hour, 4 days per week for 2 weeks). Participants were assessed by a blinded assessor twice before treatment, once post treatment and once at 4 weeks follow up on the primary outcome measure VHI and a range of secondary auditory-perceptual, acoustic, and patient (i.e., VoiSS, satisfaction) and clinician reported outcome measures (i.e., AusTOMs, attendance rates). Five Speech Language Pathologists also participated in a focus group to explore barriers and enablers to implementing intensive therapy, with questions and analyses guided by the Theoretical Domains Framework.

RESULTS

While noninferiority for the primary outcome measure VHI was not confirmed, secondary outcome measures revealed comparable within group clinically important improvements for VoiSS and the AusTOMs, as well as selected acoustic and auditory-perceptual measures for both groups. A trend of more improvements being maintained in the intensive group was identified. Comparably high satisfaction and attendance was also found between groups. Clinicians reported more enablers than barriers to providing intensive therapy which included beliefs that it led to greater progression and consolidation of patient learning, was supported by the local context and was associated with positive emotions. Barriers related to difficulties with booking and scheduling and the belief that intensive therapy was not for all patients.

CONCLUSIONS

While the current study was likely underpowered to establish non-inferiority of intensive therapy, secondary outcomes suggested that intensive therapy may produce comparable benefits to voice, wellbeing, satisfaction and attendance compared to weekly therapy and may be a viable therapy option for individuals with MTD. When implementing intensive therapy, clinicians should consider patient's preferences and availability, as well as systems which allow for flexible booking and therapy provision for patients. Clear recommendations for future research including the use of a larger sample and telehealth are also provided.

Epidemiological Patterns and Treatment Outcomes in a Private Practice Community Voice Clinic

OBJECTIVES

Voice therapy is administered by speech-language pathologists in multiple practice settings, including private practice community voice clinics. However, the evidence for diagnosis patterns and voice treatment outcomes in community voice clinics is very limited. The purpose of this study was to extend knowledge from a previous investigation by assessing the epidemiological patterns of patient referrals to a private practice community voice clinic across a 4-year period (50 months) and to measure the effectiveness of treatment outcomes for patients who were followed up with voice therapy in the same setting.

STUDY DESIGN

Retrospective case series.

METHODS

Consecutive patient records from November 2014 through January 2019 were reviewed. Patients were grouped into seven categories of distinctive diagnoses. Descriptive data for each group were extracted to determine epidemiological patterns of disorder diagnosis, voice handicap, voice quality severity, age, and gender. For patients who completed at least three treatment sessions, pre- and posttreatment measurements of two assessments, the Voice Handicap Index (VHI) and the Acoustic Voice Quality Index (AVQI), were extracted and compared using a multivariate analysis of variance.

RESULTS

Records from 454 consecutive patient referrals over a 50-month time period were reviewed. The most frequent diagnoses were multifactorial etiologies or those with only a few cases, categorized collectively as an "other" diagnosis category. Diagnoses of nonspecific dysphonia and mid-membranous lesions were also common. Consensus Auditory Perceptual Evaluation of Voice-scale scores were not different among disorders; however, group differences were found for VHI and AVQI. Treatment data were available for 292 patients, with 47 of those patients completing at least three treatment sessions and with data for pre- and posttreatment VHI and AVQI. A mixed multivariate analysis of variance showed a significant effect of treatment (Wilks' Lambda = 0.42, F[2] = 27.58, P < 0.001, ƞ_p² = 0.58), where both AVQI and VHI improved significantly across the pre- to posttreatment measurements.

CONCLUSIONS

Patient characteristics and diagnosis patterns across a 50-month period were similar when compared to a previous study that investigated epidemiological patterns in this clinic across 28 months. Voice therapy administered in this community voice clinic to patients with varied diagnoses was found to be effective based on changes in VHI and AVQI measurements.