Abstract
Objectives:
Vocal fold atrophy is increasingly identified in the geriatric population. Current literature shows varying outcomes with voice therapy. Our goal was to analyze multidimensional vocal outcomes of these patients who underwent voice therapy. Secondary aims included determining compliance and analyzing differences in patients who undergo surgery.
Methods:
197 patients with vocal fold atrophy were included and reviewed. Patients were categorized by treatment received. Patient-reported, perceptual, aerodynamic, and acoustic voice outcomes were analyzed before and after therapeutic intervention. Changes were calculated and significance determined using Wilcoxon signed-rank and rank-sum tests.
Results:
89(45%) received no therapy, 43(22%) incomplete therapy, 51(26%) complete therapy, 8(4%) surgery only, and 6(3%) therapy followed by surgery. Those who completed voice therapy showed significant improvement in voice related quality of life (VRQOL)(p=0.0225), glottal function index (GFI)(p<0.001), grade, roughness, breathiness, asthenia, strain (GRBAS)(p<0.001), maximum phonation time (MPT)(p=0.0081), and fundamental frequency in women(p=0.0024). No significant changes were found in mean airflow. When comparing patients who underwent surgery versus voice therapy, statistically significant differences were present between pre-treatment VRQOL (p=0.0269) and GFI (p=0.0166).
Conclusions:
Only 29% of patients with vocal atrophy completed voice therapy when recommended. Within this patient cohort, voice therapy results in significant improvement in multidimensional voice outcomes. Patients with vocal atrophy that undergo surgical treatment differ from those treated with voice therapy alone in their pre-treatment patient-reported measures.
Keywords: Vocal fold atrophy, presbyphonia, voice therapy, dysphonia, aging voice
Introduction
Dysphonia is a common complaint in older patients. One study estimates that about 50% of older patients experience a voice disorder in their life, with about 30% experiencing a current voice problem.1 The most common diagnosis in people over the age of 65 who present with these symptoms is presbylaryngis or vocal fold atrophy.2 With an aging global population, growing numbers of older patients are seeking medical attention for this problem.2,3
On larygoscopic exam, vocal fold atrophy is characterized by vocal fold bowing, prominent vocal process, and spindle shaped glottal gap.4 Changes in vocal fold anatomy and physiology include loss of muscle bulk and changes in the lamina propria.5 Many changes to voice production occur with age. In women, mean frequency of the speaking voice drops over the course of a lifetime from −225 Hz to −195 Hz from age 20 to age 90.6 In men, mean frequency falls until the fifth decade at which point it begins to rise until death.6 Symptoms of vocal fold atrophy include: dysphonia, breathiness, difficulty with speaking or singing, and reduced intensity.7 All of these symptoms may be distressing to older patients and may impair their quality of life and/or work. Treatment for vocal fold atrophy has focused on voice therapy, surgical therapies aimed at vocal fold medialization, or a combination of both.8-12
There are relatively few studies of the effectiveness of voice therapy on improving the symptoms of vocal fold atrophy with a large cohort looking at multidimensional outcomes. The available studies exhibit small sample sizes, varied results, or narrowly analyze voice outcome measures. Gartner-Schmidt et al showed a 36% success rate defined as improvement in voice handicap index (VHI) of >5 in patients with vocal atrophy treated with voice therapy alone.9 Berg et al examined 54 elderly patients with age-related dysphonia, 19 of whom underwent voice therapy and showed significant improvement in voice related quality of life (VRQOL).12 Kaneko et al showed significant improvement across multidimensional voice outcomes in a retrospective analysis of 16 patients.13 Ziegler et al followed 16 patients in a prospective study and found improvement in patient-reported outcomes in those who received vocal function exercises however did not analyze multidimensional voice outcomes.14 Interestingly, these studies and others have shown that after diagnosis with vocal fold atrophy, few patients complete any form of treatment.8,9,15-17
The purpose of this study is to analyze multidimensional voice outcomes (patient reported, perceptual, aerodynamic, and acoustic voice measures) of patients who underwent voice therapy for vocal fold atrophy to better understand outcomes from this form of treatment. Our secondary aims are to evaluate adherence to prescribed voice therapy and to analyze differences in patients who underwent treatment with surgical intervention from those treated with voice therapy for vocal fold atrophy.
Methods
This study was approved by the Institutional Review Board at the University of North Carolina (IRB# 16-1039).
Participants
Using the i2b2 technology through the North Carolina Translational and Clinical Sciences (NC TraCS) Institute at the University of North Carolina at Chapel Hill, a query of the University of North Carolina Voice Center database between 2005 and 2015 was run for all patients over 50 and the ICD 9 (478.5) and ICD 10 (J38.3) codes for “other diseases of the vocal cords.” This query yielded 1115 patients. This selection was further filtered for patients with a diagnosis of vocal fold atrophy. Patients with other pathology to explain dysphonia were then excluded. Excluded diagnoses included benign vocal fold lesions, laryngeal cancer, vocal scar, laryngotracheal stenosis, or neurologic conditions. One hundred ninety-seven patients diagnosed with vocal fold atrophy were identified. All patients received an evaluation by one of two fellowship-trained laryngologists and a voice-specialized speech language pathologist (SLP) at the UNC Voice Center. This evaluation included a thorough medical history, focused head and neck exam, videostroboscopy, patient reported outcomes, perceptual measure of voice, and aerodynamic and acoustic measures of voice. All patients who were considered stimulable for voice therapy by the voice specialized SLP at the UNC Voice Center were recommended to therapy as first-line treatment. The UNC Voice Center is made up of two voice specialized SLPs who underwent the same training. They were considered the trained listener group and decided who was stimulable for voice therapy. There was no objective criteria for surgical intervention. This was determined on an individual basis between the patient and surgeon taking into account a variety of patient factors including cost, time, patient preference, motivation, and belief systems with regards to treatments.
Data Collection
Retrospective chart review of the 197 patients diagnosed with vocal fold atrophy at the UNC Voice Center was undertaken. Data collected included voice related quality of life (VRQOL), glottal function index (GFI), grade, roughness, breathiness, asthenia, and strain (GRBAS), mean airflow, maximum phonation time (MPT), fundamental frequency, and soft phonation index (SPI) at multiple time points: initial visit, prior to any intervention and after treatment with voice therapy. For patients who underwent surgical intervention, data was also extracted before and after treatment. For those who underwent injection augmentation, follow up data was collected between two weeks and two months post-injection to capture effect of the intervention. For patients who underwent medialization thyroplasty, follow up data was collected between one and six months. For patients who received voice therapy, follow up data was collected at discharge from therapy after 6-10 sessions as determined by the therapist.
Patient reported outcomes included VRQOL and GFI. VRQOL is a validated patient-completed survey of 10 questions evaluated on a 5-point scale (0-4) measuring the physical, social, and emotional impact of dysphonia. The 10 items are summed to an overall score (0-100) where higher scores indicate a better perceived voice-related quality of life.18 GFI is a validated patient-completed survey of glottal function comprising 4 questions. Each item is graded on a 6 point scale (0-5) and summed to a total score (0-20) in which a higher score indicates worse perceived glottal function.19 GRBAS is an anchored perceptual analysis of voice by a trained listener (a voice specialized SLP at UNC Voice Center). It assesses voice quality on a 4-point scale (0-3) each for grade, roughness, breathiness, asthenia, and strain. The subscales are summed to give a total score (0-15) where a lower score indicates better vocal quality.20 The trained listener who made the GRBAS assessment was one of two voiced specialized SLPs at UNC Voice Center, but not necessarily the same person who provided the treatment.
Acoustic measures collected and analyzed included fundamental frequency and soft phonation index. Acoustic measures were assessed using the Pentax Medical Computerized Speech Lab (CSL™) Model 4150 or 4150B. Aerodynamic measures collected and analyzed included mean airflow during comfortable sustained phonation, assessed using the Pentax Medical Phonatory Aerodynamic System (PAS): Model 6600, and maximum phonation time.
Therapy
Voice therapy at the UNC Voice Center was performed by a speech language pathologist (SLP) specializing in treating voice disorders. Therapy included exercises targeting glottic insufficiency, education about vocal hygiene, and anatomy and physiology of the subsystems of vocal production: respiration, phonation, and resonance. Patients were seen for 6-10 sessions over the course of several months; therapy length was determined individually between the therapist and the patient and was based on achievement of stated treatment goals in patient’s plan of care. Patients were taught vocal function exercises (VFEs), an evidenced based approach designed to restore balance to the disordered voice. The program consists of four exercises that target vocal efficiency and strengthening of laryngeal musculature: warm-up, stretch, contract, and power phase. All exercises are performed as softly as possible, using a forward placement.13,21 Patients were provided detailed instructions for regimented home exercise – two times per day, morning and evening. Other skilled therapeutic interventions were also used to address the individual needs of each patient, at the discretion of the treating SLP. These exercises included lower abdominal support for breathing during phonation, alternative semi-occluded vocal tract exercises (e.g. straw phonation, lip/tongue trill exercises, etc.), and resonant voice and conversation therapy for generalization of improved voice function to conversational speech or to address concomitant diagnoses such as muscle tension dysphonia.22-25
Statistical Analysis
VRQOL and GFI was collected before and after treatment with either complete voice therapy alone or after surgery. Full voice analysis including GRBAS, mean airflow, maximum phonation time, fundamental frequency, and soft phonation index was performed by one of two voice specialized SLPs at the UNC Voice Center. The differences before and after treatment were analyzed using the Wilcoxon signed-rank test. The change in each voice measure from initial visit to post-therapy was compared to the change in each voice measure from initial visit to post-surgery using the Wilcoxon rank-sum test. A p-value of less than 0.05 was considered significant. Statistical tests were performed using Stata 14 statistical software (StataCorp, College Station, TX).
Results
The mean age of the 197 patients with vocal fold atrophy was 70.9 years (51-94, SD 10.15). Eighty-six patients were female, and 111 patients were male. Patients were categorized into five groups: patients who did not undergo any treatment (no treatment), patients who received some voice therapy but did not have follow up assessment (some therapy, no follow up), patients who completed prescribed voice therapy and had follow up assessment (therapy and follow up), patients who underwent a combination of upfront voice therapy followed by surgical intervention (therapy then surgery), and patients who underwent primary surgical therapy (injection augmentation and/or medialization thyroplasty) (surgery). No data was collected on why patients chose not to return for voice therapy or follow up.
Seven patients underwent injection augmentation and seven patients underwent injection augmentation followed by ultimate medialization thyroplasty. Patients who received voice therapy followed by surgery (n=6) (injection augmentation and/or medialization thyroplasty) did so because they did not demonstrate significant improvement with therapy based on patient-reported outcomes (VRQOL and GFI) as well as voice analysis by voice specialized SLP including GRBAS. Passessment by a trained listener. Patients who received primary surgical intervention (n=8) in lieu of voice therapy did so for a variety of reasons, and this was an individual decision between the primary surgeon and the patient, some of these reasons included: believing themselves too busy for therapy, not being motivated to complete therapy, already having been counseled on surgical intervention for vocal fold atrophy at another institution, and no access to voice therapy. The breakdown of the vocal fold atrophy cohort may be seen in Table 1.
Table 1:
Breakdown of Atrophy Cohort
| N | Percent of Total | |
|---|---|---|
| No treatment | 89 | 45% |
| Some Therapy No Follow Up | 43 | 22% |
| Therapy and Follow Up | 51 | 26% |
| Therapy then Surgery | 6 | 3% |
| Surgery | 8 | 4% |
There was significant improvement in patient-reported outcomes following treatment with voice therapy; VRQOL improved (p=0.0225) as did GFI (p<0.001). The perceptual measure of voice (GRBAS) also improved significantly (p<0.001). Fundamental frequency was significantly raised in women from a median of 191 Hz to a median of 230 Hz (p=0.0024). However, the change for men from a median of 126 Hz to a median of 131.5 Hz was not significant. Maximum phonation time did show significant improvement with speech therapy (p=0.0081). Soft phonation index and airflow had no significant change with voice therapy treatment. Table 2 shows the median value with interquartile range for each voice measure pre- and post- speech therapy. Patients treated surgically also showed significant improvement in VRQOL, GFI, GRBAS, and fundamental frequency in males (table 3).
Table 2:
Median Voice Measures Before and After Voice Therapy
| Voice Measure | Therapy Only | |||||
|---|---|---|---|---|---|---|
| N | Initial Visit | Post-Therapy | p value | |||
| Median | Interquartile Range |
Median | Interquartile Range |
|||
| VRQOL | 51 | 77.5 | 35 | 82.5 | 27.5 | 0.0225 |
| GFI | 49 | 9 | 7 | 4 | 8 | <0.001 |
| GRBAS | 42 | 10 | 2 | 6.5 | 3 | <0.001 |
| Airflow | 40 | 210 | 130 | 180 | 100 | 0.3496 |
| Fundamental Frequency | ||||||
| Males | 28 | 126 | 20.67 | 131.5 | 31.5 | 0.707 |
| Females | 15 | 191 | 67.36 | 230 | 39 | 0.0024 |
| Soft Phonation Index | 29 | 18.327 | 15.12 | 19.17 | 15.14 | 0.4688 |
| Max Phonation Time | 43 | 13 | 9 | 16 | 9.5 | 0.0081 |
VRQOL = voice related quality of life; GFI = glottal function index; GRBAS = grade, roughness, breathiness, asthenia, and strain; N= number of patients
Table 3:
Median Voice Measures Before and After Surgery
| Voice Measure | Received Surgery | |||||
|---|---|---|---|---|---|---|
| N | Initial Visit | Post-Surgery | p value | |||
| Median | Interquartile Range |
Median | Interquartile Range |
|||
| VRQOL | 13 | 65 | 32.5 | 82.5 | 30 | 0.0499 |
| GFI | 13 | 12 | 7 | 4 | 6 | 0.002 |
| GRBAS | 12 | 9.5 | 1 | 8 | 2 | 0.0334 |
| Airflow | 12 | 180 | 230 | 165 | 145 | 0.1817 |
| Fundamental Frequency | ||||||
| Males | 8 | 133.805 | 75.965 | 107.65 | 29.15 | 0.0296 |
| Females | 4 | 224.14 | 207.86 | 241 | 187 | 0.5775 |
| Soft Phonation Index | 7 | 40.42 | 33.62 | 18.46 | 30.58 | 0.3105 |
| Max Phonation Time | 12 | 17.5 | 13.5 | 14.5 | 11.75 | 0.8441 |
VRQOL = voice related quality of life; GFI = glottal function index; GRBAS = grade, roughness, breathiness, asthenia, and strain; N= number of patients
When comparing those treated with voice therapy versus those treated surgically, there was a significant difference in the change before and after treatment with respect to GRBAS, which showed a greater improvement for the voice therapy group with a median improvement of 3 points versus the surgery group with a median improvement of 1 point (p=0.0147). Table 4 shows the median differences in voice measures for the group that completed prescribed voice therapy (n=51) and the group that received surgical therapy (n=14).
Table 4:
Comparison of Median Difference in Voice Measures for Therapy Only and Surgery Groups
| Therapy | Surgery | ||||||
|---|---|---|---|---|---|---|---|
| Difference | Difference | ||||||
| N | Median | Interquartile Range |
N | Median | Interquartile Range |
p-value | |
| VRQOL | 51 | 5 | 15 | 13 | 20 | 27.5 | 0.1085 |
| GFI | 49 | −3 | 6 | 13 | −5 | 10 | 0.2085 |
| GRBAS | 42 | −3 | 2 | 12 | −1 | 1.5 | 0.0147 |
| Airflow | 40 | 0 | 100 | 12 | −30 | 160 | 0.5643 |
| Fundamental Frequency | |||||||
| Males | 28 | 0.5 | 38 | 8 | −9.25 | 23.35 | 0.0939 |
| Females | 15 | 56 | 66 | 4 | 2 | 42.86 | 0.121 |
| Soft Phonation Index | 29 | 3.734 | 16.08 | 7 | −6.474 | 56.48 | 0.3081 |
| Max Phonation Time | 43 | 1.5 | 5 | 12 | 1 | 5.75 | 0.3026 |
VRQOL = voice related quality of life; GFI = glottal function index; GRBAS = grade, roughness, breathiness, asthenia, and strain; N= number of patients
There was a significant difference in initial patient reported outcomes between treatment groups. The surgical group reported a lower median VRQOL of 65 versus the therapy group with a median VRQOL of 77.5 (p=0.0269). The surgical group also reported a significantly worse GFI of 12 versus 9 for the therapy group (p=0.0166). However, there was no significant difference in initial GRBAS, or any acoustic or aerodynamic measures at initial presentation. Table 5 shows the comparison between the initial measures of voice for the group that completed prescribed voice therapy and the group that received surgical therapy.
Table 5:
Comparison of Median Voice Measures at Initial Visit for Therapy Only and Surgery Groups
| Voice Measure | Therapy | Surgery | |||||
|---|---|---|---|---|---|---|---|
| Initial Visit | Initial Visit | ||||||
| N | Median | Interquartile Range |
N | Median | Interquartile Range |
p-value | |
| VRQOL | 51 | 77.5 | 35 | 13 | 65 | 32.5 | 0.0269 |
| GFI | 51 | 9 | 7 | 13 | 12 | 7 | 0.0166 |
| GRBAS | 47 | 10 | 2 | 13 | 9 | 1 | 0.8075 |
| Airflow | 45 | 210 | 150 | 13 | 180 | 190 | 0.6542 |
| Fundamental Frequency | |||||||
| Males | 31 | 126 | 21 | 8 | 133.805 | 75.965 | 0.7279 |
| Females | 16 | 196 | 62.18 | 5 | 226 | 63.72 | 0.2648 |
| Soft Phonation Index | 34 | 20.859 | 15.86 | 13 | 25.471 | 28.04 | 0.0945 |
| Max Phonation Time | 47 | 12 | 7 | 13 | 17 | 12 | 0.2427 |
VRQOL = voice related quality of life; GFI = glottal function index; GRBAS = grade, roughness, breathiness, asthenia, and strain; N= number of patients
There was no significant difference between the change in VRQOL before and after treatment between the group that received voice therapy only and the group that received surgery. There was no significant difference between the change in GFI before and after treatment between the two treatment groups.
Discussion
The proportion of the US population over age 65 is growing rapidly with a high incidence of dysphonia, commonly related to vocal fold atrophy. Treatment options include: voice therapy, surgical intervention, or a combination of both. This study was undertaken with the expressed purpose of determining the efficacy of voice therapy for treating vocal fold atrophy in an elderly population. Previous studies investigating this topic have reported variable treatment outcomes. These data, however, have often been limited by small treatment cohorts and limited outcome measure reporting. A comprehensive investigation of concurrent acoustic, perceptual, and patient reported outcomes following intervention has been lacking.
In our retrospective analysis, both patient reported outcomes (VRQOL and GFI) and perceptual measure of voice significantly improved in patients who participated in a course of voice therapy. Additionally, maximum phonation time and fundamental frequency in females significantly increased. Improvement was noted in multiple different realms of outcome measures including: self reported, perceptual, as well as aerodynamic and acoustic. These data reinforce the effectiveness of prescribed voice therapy by a trained speech language pathologist (specializing in voice) for patients suffering from vocal fold atrophy.
Although dysphonia related to vocal fold atrophy is common among the geriatric population, we documented a low proportion of patients actually completing the prescribed treatment.16,17 Despite significant improvements in multidimensional outcomes with voice therapy, in this cohort, only 29% of recommended patients completed a full course of prescribed voice therapy. This is lower then prior studies by Gartner-Schmidt et al (44%) and Berg et al (35%).9,12 Based on our experience with this cohort, we believe the barriers to treatment may have included lack of understanding of efficacy of treatment, other health issues, transportation or cost issues, or lack of time. This is consistent with Young et al’s paper which considers patient reported reasons for not pursueing therapy.8 They found that the most common reason for not pursueing therapy in their cohort was lack of significant symptomatology and reassurance by lack of malignancy.8 We believe with the scarcity of data to aid in counseling by the practioner, the low retention may be more related to lack of confidence in the effectiveness of therapy by patients than previously thought. Higher clinical volumes of practioners and less face-to-face time for counseling may further contribute to this issue and decline in participation. Young et al. attempted to answer this question and found that in their cohort, 56% wanted to pursue treatment after receiving a diagnosis of vocal fold atrophy.8 They found that among the most common reasons patients chose to forgo voice therapy was not believing they would benefit from therapy. With our data, clinicians may be better equipped to improve counseling surrounding the benefits of voice therapy to increase awareness, adherence, and in turn better outcomes and quality of life.
We found it intriguing that only the female cohort demonstrated a significant post-treatment change (elevation) in the fundamental frequency of the voice. One potential explanation for this finding is that low frequency and deepening of the voice is a more significant motivator for women to seek treatment for vocal fold atrophy than it is for men. This awareness of the fundamental frequency change may have also been a primary target area for their voice improvement.
We were surprised to find no difference in the change in patient reported, acoustic, or aerodynamic measures of voice before and after treatment when comparing the surgical group to the therapy treatment group. In fact, the only voice measure that differed between the surgery and therapy groups was GRBAS. Patients who had therapy demonstrated a significantly better final GRBAS and a significantly larger pre-post change than did the surgery group.
There were, however, significant differences in patient reported outcomes (VRQOL and GFI) before initiating treatment. Our data suggest that those who chose to undergo surgical treatment for vocal fold atrophy had more severe symptoms as measured by their patient reported outcomes. This group may be more motivated to pursue a more invasive treatment.
Strengths of this study included the large sample size for patients who completed therapy, and the multiple voice outcome measurements collected before and after voice therapy. One limitation was the lack of a “no-therapy” control group. Patients who chose not to complete voice therapy did not return for repeat voice measures which limited our ability to directly compare the results from the therapy group to the no therapy group. An additional limitation was the small sample size of patients who went on to injection augmentation and thyroplasty for comparison to the therapy group as a secondary aim. Similarly, the small sample size of patients who received injection augmentation and/or thyroplasty limited our ability to determine if there was a significant difference in outcomes for patients who received surgery alone versus voice therapy followed by surgery. Also present was the limitation of data collection in a retrospective chart review which included incomplete and missing data points. Moving forward, it will be interesting to directly compare patients who undergo injection augmentation and/or thyroplasty to patients who receive therapy to determine if surgical treatment is superior to voice therapy when controlling for severity in patients with vocal atrophy. An additional field of study would be to compare outcomes for patients who first complete voice therapy versus those who go straight to surgery.
Conclusion
29% of patients with vocal atrophy completed voice therapy when recommended. Within this patient cohort, voice therapy resulted in significant improvement in patient-reported, perceptual, acoustic, and aerodynamic measures of voice. While patients showed significant improvement with either voice therapy or surgical therapy; those that underwent surgical treatment demonstrated greater severity on their pre-treatment patient-reported outcomes. With a growing elderly population and consequent increased incidence of voice disorders, voice therapy should be considered an effective primary intervention for vocal fold atrophy patients seeking symptomatic improvement.
Funding:
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the UNC-CH Summer Research Training in Aging for Medical Students [T35-AG038047].
Footnotes
Conflict of Interest:
The Authors declare that there is no conflict of interest.
Financial Disclosure: The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: UNC-CH Summer Research Training in Aging for Medical Students (T35 AG038047)
Conflict of Interest: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Meeting Information: Poster presentation at the 97th American Broncho-Esophagological Association meeting at Combined Otolaryngology Spring Meetings, San Diego, California, USA, April 27, 2017.
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