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Cite this article: Abbasova A, Ozkan ET (2018) Features of Voice Therapy Patients of the Education, Research and Training Centre for Language and Speech Disorders in Turkey. Ann Otolaryngol Rhinol 5(2): 1206.

*Corresponding author

Afaq Abbasova, Department of Speech and Language Therapy, ENT, Azerbaijan Medical University, S. Vurgun, 167, Baku, Azerbaijan, AZ1022, Turkey, Tel: (+994 12) 597-37-06; (+994 55) 921-06-03; Fax: (+994 12) 597-38-98; Email:

Submitted: 14 February 2018

Accepted: 12 March 2018

Published: 14 March 2018

ISSN: 2379-948X

Copyright© 2018 Abbasova et al.

OPEN ACCESS

Keywords•Voice therapy•Epidemiology•Diagnose•Attendance

Abstract

Objectives: Voice therapy is one of the options for management of dysphonia. Therapy attendance affects the voice therapy outcome. The aim of this study is to analyze the demographic features of voice therapy patients in Turkey and patient’s attendance to voice therapy.

Methods: 468 dysphonic patients (279 female, 179 male), aged between 4-74 years, were included in this study. Their documents analyzed retrospectively. Patients’ age, gender, professions, diagnosis, and attendance to therapy were analyzed.

Results: The patients were divided into two age groups: 4-18 years were in the pediatric group, and 19-74 years were in the adult group. The most prominent professions among the patients of the adult group were teacher, homemakers and students. The predominant diagnoses among children who were directed to voice therapy were vocal nodules, mutational falsetto and functional dysphonia. The predominant diagnoses among the adults were vocal nodules, functional dysphonia, and vocal fold paralysis. 50,21% of the total patient underwent voice therapy. 27,14% of the patients who were referred for voice therapy didn’t begin therapy after the first assessment by a speech and language therapist. 54 patients had attended to 3-6 therapy sessions, whereas 52 patients had attended to only 1 or 2 therapy sessions, and because of several reasons they dropped out from the voice therapy programme.

Conclusions: Adults were directed to voice therapy more frequently than children. The frequent diagnoses of patients who were referred for voice therapy were nodules and functional dysphonia. A high percentage of nonattendance to voice therapy sessions was observed.

ABBREVIATIONSDILKOM: Education, Research and Training Centre for

Language and Speech Disorders; ENT: Ear, nose and throat; MDVP: Multi Dimensional Voice Program; VHI: Voice Handicap Index; GRBAS: Grade, Roughness, Breathiness, Asthenia, Strength; US: United States

INTRODUCTIONPrevalance of voice disorders in general population is

variable. It changes from 6% to 30% [1, 2]. Prevalance of voice disorders among professional voice users is relatively high and it reaches 50% [3,4]. The prevalence rate is higher among females as compared to males, but in males it increases with age [5]. There are not any studies about these datas in Turkey. This study aimed to analyze some features, such as age, gender and profession of voice therapy patients in Turkey.

Causes of voice disorders are generally categorised into two groups as organic and functional [6]. There are some studies

which investigated the most frequent diagnoses among patients with dysphonia. These diagnoses overall were acute laryngitis, nonspecific dysphonia, benign vocal fold lesions, and chronic laryngitis [5]. According to another study, which investigated the prevalence of perceived dysphonia and its correlation with the prevalence of clinically diagnosed laryngeal disorders, the most encountered pathologies apart from these were Reinke’s edema, laryngeal paralysis, granulomas, epiglottic cyst [7]. Etiologies of voice disorders are different according to the age groups. Vocal fold nodules and cysts are predominant in children, functional dysphonia and reflux in adults, and presbyphonia and Reinke’s edema in the elderly [8]. This study aimed to determine the diagnoses which are often directed to voice therapy in Turkey.

There are three options for management of dysphonia: medical treatment, phonosurgery and voice therapy. Voice therapy can be applied to many voice disorders alone or in combination with medical/surgical treatment [6]. However, the studies about effects of the voice therapy generally focused on two diagnoses: functional and organic dysphonia [9-11].

Research Article

Features of Voice Therapy Patients of the Education, Research and Training Centre for Language and Speech Disorders in TurkeyAfaq Abbasova1* and Elçin Tadihan Ozkan2

1Department of Speech and Language Therapy, ENT, Azerbaijan Medical University, Turkey2Department of Speech and Language Therapy, Anadolu University, Turkey

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But there are not any studies which focused on more frequent diagnoses which were directed to voice therapy.

Outcomes in voice therapy are, in part, related to therapy attendance, but there are few studies which investigate the attendance to voice therapy. According to the literature, 38% of the patients who were referred for voice therapy did not attend the initial session, and voice therapy dropout rates ranged from 44% to 65% [12-14]. This therapy also aimed to analyze patient’s attendance to therapy.

MATERIALS AND METHODS

Design and the Procedure

The study used a retrospective observational design. 474 patients’ folders, between 2001-2016 years, were analyzed for the demographic features of patients with dysphonia in order to determine both the diagnoses for which the patients were directed to voice therapy in Turkey and patients’ attendance to voice therapy. These dysphonic patients were directed to Education, Research and Training Centre for Language and Speech Disorders (DILKOM)– the biggest speech and language therapy center in Eskişehir, Turkey. Most of the dysphonic patients were directed to our center by ear nose throat (ENT) doctors and they had reports about their disorders. Others, who applied to the center by themselves or who were directed by other professionals, were consulted by an ENT doctor.

All dysphonic patients were evaluated by a speech and language therapists who specialised in voice. They were done videostroboscopy with a rigid telescope 70° (Key Pentax, US), an acoustic analysis (Multi Dimensional Voice Program-MDVP) and auditory perceptual analyses (Voice Handicap Index-VHI and GRBAS). Results of examinations are saved in patients’ folders which were numbered in the chronological order of arrival to the center.

The following parameters were collected from the folders and analyzed: age, gender, profession, diagnoses, and information about voice therapy. Information about voice therapy included if patients received therapy or not, if they did, how many sessions they attended.

Statistical Analysis

Descriptive statistics was used for presentation results. Results are viewed in tables and charts. To compare the parameters between genders and age groups, a chi-square test was performed.

RESULTS AND DISCUSSION

Results

Demographic: 474 dysphonic patients’ folders were selected in order to analyse the data. İn 6 folders there weren’t datas which was aimed analysis. That’s why they were excluded from the study. Thus, 468 patients’ folders were included in the study.

There were 279 female (59,62%) and 179 male (40,38%) patients. The patients’ ages ranged from 4 to 74 years. 4-18 year old patients were categorized as pediatric group (24,78%, n=116). 19-74 years of age were categorized as adult group

(75,21%, n=352). The χ2 analysis showed a significant difference in gender by age grouping (P<0,001). However, there was male dominance (68,1%) in the pediatric group, and female dominance (68,75%) among the adult group (Table 1).

34,09% of the adult dysphonic patients were professional voice users. There were teachers, preachers, homemakers, call center workers, singers and actors, lawyers, salespeople, secretaries in this group. The three most prominent groups among professions were teachers (n=66), homemakers (n=64), and students (n=48) respectively (Table 2).

Laryngeal Diagnoses

The percentage of patients who were directed by ENT doctors were 85,47% (n=400) and they had been reported with diagnosis of several dysphonias. Other 14,53% (n=68) patients applied to the center by themselves or they were referred by singing masters, teachers or other doctors with different professions like neurologist, psychiatrist, etc. These patients referred to ENT doctors immediately after the voice evaluation. They had therapies after they were diagnosed by ENT doctors too. All patients with voice complaints were evaluated by a voice-specialized speech and language therapist during the first meeting.

The first three predominant laryngeal diagnoses among children who were directed to voice therapy by ENT doctors in Turkey are vocal nodules (52,59%; n=61), mutational falsetto (16,38%; n=19) and functional dysphonia (13,79%; n=16) (Table 3). Two thirds of children with vocal nodules and functional dysphonia were boys.

Table 1: Age and gender data of patients.

Age groups Female (N) Male (N)

Total (N; %)

Children (4-18) 37 79 116 (24,78%)

Adults (19-74) 242 110 352 (75,21%)

Total(N; %) 279 (59,62%) 189 (40,38%) 468

Table 2: Professions of adult patients.

Professions Number of patients (% of adults)

Teacher 66 (18,75)Homemaker 64 (18,18)Student 48 (13,63)Workman 43 (12,22)Pensionary 27 (7,7)Preacher 14 (3,98)Singerandconservatory’sstudent 12 (3,41)Actor 7 (1,99)Call centerworkers 7 (1,99)Salespeople 5 (1,42)Others (doctor, nurse, engineer, architect, manager, police) 38 (10,80)

Unstated 21 (5,97)Total 352

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The three predominant laryngeal diagnoses among adults who were directed to voice therapy were vocal nodules (24,43%; n=86), functional dysphonia (17,05%; n=60), and vocal fold paralysis (13,07%, n=46) (Table 4). There was a notable predominance of females among cases with vocal nodules and functional dysphonia. In fact, 87% of the cases with vocal nodules and 70% of the patients with functional dysphonia were females. It was determined that 52,17% (n=24) of the cases with vocal fold paralysis were post thyroidectomy surgery.

Attendance to Voice Therapy

72,86% (n=341) of the patients with voice disorders who were referred to our center began voice therapy after assessment. Thus, 341 cases were taken to the therapy, of which 235 (50,21%) patients completed it. Only 54 patients (11,54%) had 3-6 therapy sessions and they dropped out from the voice therapy programme. 52 therapy patients (11,11%) had only 1 or 2 therapies and also they dropped out from the programme too. 27,14% (127 cases) of all study participants didn’t come back

after the evaluation for voice therapy although they had been referred to voice therapy (Figure 1).

There was a significant difference in attendance to voice therapy by age groups (p<0,001). 15,52% of children didn’t apply for the voice therapy after the evaluation by a speech and language therapist, and 69,83% of the children completed it. Only 14,66% of the children dropped out from the voice therapy programme. These figures were as the following among adults: 28,98% of adults didn’t apply for the therapy after the evaluation session; 43,75% of them completed the therapy; and 27,27% of them dropped out (Figure 2).

DISCUSSIONThis research represents the demographic features, diagnoses

of voice therapy patients in Turkey and their attendance to therapy.

According to our research, adult patients are being directed to voice therapy more than children. Children patients constitute only one fourth (25%) of all population although prevalance of voice disorders among children is not less than adults. The reported frequency of occurrence of voice disorders in school age children ranges from 6% to 23% [15, 16]. Carding et al. [17] examined the prevalence of dysphonia in a large cohort of children [n=7389] at 8 years of age. The prevalence of dysphonia according to research clinicians was 6% compared to a parental report of 11%. In a Swedish study of 205 children from different parts of the country with the age of 10 years, the prevalence of hoarseness was 14% [18]. The presence of voice disorders in a large population (n=2445) of preschool children was investigated by Duff et al. They reported that 3.9% of the 2445 preschool children aged from 2 to 6 had hoarseness [19]. These figures are not lower than those of the prevalance of voice disorders in adults. In a study which investigated epidemiological data of a large population (n=2019) with voice diseases by Garcia Martins et al.,children aged between 1-18 years corresponded to 18% of the population. Our findings corroborate this result. However, in that research children aged between 1-6 years constituted one third of all children patients [8]. In our study only 16,38% (19/116) of all children patients were from 4 to 8 years. Taking into account of all these, we can conclude that children with dysphonia are directed to voice therapy relatively fewer than adults in Turkey. The reason is probably the fact that it is difficult to examine the children, that parents do not think dysphonia as a health issue and that the children are not getting into voice therapy easily.

This study confirmed the clear predominance of males in pediatric population (4-18 years) and females in adults (19-74 years). 68,1% of the children were male and 68,75% of the adults were female (Figure 3). Our results are being supported by the findings of other studies [4,5,8,17]. Some studies could not find any difference between genders according to age groups like the present study. However, in one of such studies which investigated prevalence of voice disorders in preschoolers aged between 2-6 years, there wasn’t statistically significant difference for presence of voice disorders in males and females [19]. The percent of preschoolers in the present study population is limited. That’s why the results of this study can’t be compared with that study.

Table 3: Laryngeal diagnosis of children.

Laryngeal diagnosis Number of patients (% of children)

Vocal nodules 61 (52,6)Mutational falsetto 19 (16,4)Functional dysphonia 16 (13,8)Muscule tension dysphonia 6 (5,2)Psychogenic aphonia/dysphonia 4 (3,4)VC paralysis 3 (2,6)VC cyst 3 (2,6)Vocal sulcus 2 (1,7)VC postop case 2 (1,7)Total 116

Table 4: Laryngeal diagnosis of adults.

Laryngeal diagnosis Number of patients (% of adults)

Vocal nodules 86 (24,4)Functional dysphonia 60 (17,0)VC paralysis 46 (13,1)Muscle tension dysphonia 34 (9,7)VC postoperative case 25 (7,1)Laryngopharyngeal reflux 24 (6,8)VC cyst 11 (3,1)Post laryngectomy 9 (2,6)Mutational falsetto 8 (2,3)Psychogenic aphonia/dysphonia 8 (2,3)VC polyp 7 (2,0)VK benign lesions [cyst or nodule?] 7 (2,0)Reinke’s edema 7 (2,0)Vocal sulcus 6 (1,7)Spasmodic dysphonia 6 (1,7)Presbiphonia 5 (1,4)Myasthenia 1 (0,3)Contact ulcer 1 (0,3)Vocal hemorrhage 1 (0,3)Total 352

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2019 patients with dysphonia, domestic employees, students and teachers have been reported as the predominant professions [8]. Our results are similar with those of that study; but the frequency is different. In a lot of studies a high frequency of occurrence of voice disorders was shown among teachers, and prevelance figures among them change from 20 to 50%. Many studies assert that teachers suffer from voice disorders more frequently than others in general populations [4, 21].

According to the results of the present study, predominant laryngeal diagnoses were vocal nodules, mutational falsetto and functional dysphonia among dysphonic children. Vocal nodules were the most frequent diagnoses among dysphonic children. About half of all children (52,59%) were identified with vocal nodules in this study. This result supports other studies’ results in the literature [8,22-24]. As follows, in the study of Garcia Martin et al., vocal nodules were diagnosed in 57% of 304 children aged between 4-18 years and in the study of Smillie et al., it was diagnosed in 52% of 154 children aged between 1-16 years [23, 24]. In another study, the predominant diagnosis in all three age groups of children (1-6;7-12;13-18 years) was vocal nodules [8]. Similar to previous studies, our study showed that males represented the majority of the dysphonic children population.

The second frequent diagnosis among children was puberphonia (16,38%). It needs to be written down that this diagnosis was identified only in males. Probably, the cause of this result was the fact that the pitch changes in puberty are less dramatic for the females.

Vocal nodule and functional dysphonia were also the predominant diagnoses (24,43% and 17,05%) among dysphonic adults who were directed to voice therapy. These diagnoses are among predominant causes of dysphonia in literature, but they are not always the first predominant diagnoses depending on research population. In a retrospective study of data from a large, nationally representative administrative U.S. claims database, acute laryngitis was the most common dysphonia diagnosis. In that study, the other common dysphonia diagnoses were nonspecific dysphonia, benign vocal fold lesions, and chronic laryngitis. That is to say acute laryngitis was diagnosed most closely by primary care physicians, but nonspecific dysphonia, chronic laryngitis, and laryngeal pathology by otolaryngologists [5]. As in other reports describing laryngeal disorders in 731 children evaluated by otolaryngologists, subglottic stenosis was the first most frequent laryngeal pathology. The other most common pathologies were vocal nodules, laryngomalacia, functional dysphonia and vocal fold paralysis. The data were collected at a major children’s hospital otolaryngology clinic where more extreme medical conditions were treated [25].

In the present study, the third predominant laryngeal diagnosis among adult population was VCP (13,07%). The most common cause (52,17% of cases) of VCP was tyroidectomy. Although some authors have suggested that thyroid surgery is decreasing as a cause for VCP due to improved techniques, thyroidectomy is still the most common reason causing VCP in literature [26-28]. Our result supports studies that documented the causes of laryngeal paralysis. A study found that surgery was the most common cause of VCP (40,2% of 291 cases) and thyroidectomy represented the most common surgery for VCP

Figure 1 Attendance to therapy of dysphonic patients.

Figure 2 Attendance to therapy by age groups.

Figure 3 Ratio of gender among age groups of dysphonic patients.

Another study found that laryngeal pathologies were relatively more in males than females (7,2% and 5% in accordance). They studied 428 otolaryngology patients, and males were found to be more than females (262 males/ 166 females); but patients with functional dysphonia were not included in it [20].

Another finding in the present study is the fact that one third of adult patients (120/ 352) with voice complaints were professional voice users. They were teachers, preachers, call center workers, singers and actors, lawyers, salespeople, secretaries and trainers. It confirms the relation between dysphonia and heavy vocal use. The studies denote that professional voice users suffer more frequently from voice disorders than the general population [3,4]. It’s an expected condition due to the fact that professional voice users are required to speak and/or to sing for long periods.

The results of the study also indicate that the predominant professions which are directed to voice therapy were teachers, homemakers and students in Turkey. In study, which evaluated

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(57 cases) [26]. Another study found that surgery contributed to increased incidence of postoperative RLNP [28]. According to other authors, thyroidectomy is the main cause for bilateral paresis in adults [27,29,30]. But we didn’t investigate the causes of unilateral and bilateral VCP separately in our study.

Consequently, we think our results don’t represent the frequent causes of dysphonia in fact. They represent predominant diagnoses which are directed to voice therapy.

As mentioned before, this study presents that most of the therapy patients were directed by ENT doctors (85,47%). This is an expected result such that if a person has a voice complaint, s/he consults to an ENT doctor in Turkey. After the medical exam, the ENT doctor directs the patient for voice therapy if it is required. In a retrospective study which analysed referrals to speech and language therapy in 11 centres, it is showed that referrals from ENT surgery have risen from 1987 to 1995. ENT services were in the top five referrers in 1995 [31].

This study investigated the attendance to voice therapy too. Only half of the population (50,21%) completed the voice therapy. 27,14% of the patients who were referred for voice therapy didn’t return after the evaluation session by a speech and language therapist. Results showed that 15,52% of the children didn’t apply for voice therapy after the evaluation by a speech and language therapist and 69,83% of them completed it. These figures were 28,98% and 43,75% among adults properly. According to our results, though children were directed to therapy fewer than adults, their rates of completion of therapy were higher. 22,65% of all patients dropped out after beginning the therapy sessions:11,54% (54 patients) had 3-6 therapy sessions but didn’t complete the voice therapy programme. 11,11% (52 patients) had only 1 or 2 therapies. There are few studies in literature about attendance to voice therapy. In a review of patient adherence to the recommendation for voice therapy, Portone et al. showed that47% of voice therapy patients have been recorded as not returning after the initial speech-language pathology evaluation. They investigated the primary reasons for nonattendance and reported that insurance denials, healing spontaneously, and distance to the clinic were the primary reasons for nonattendance [12]. Our rates were low, and we didn’t search the reasons of nonattendance to therapy. In another study of the same authors, it was found that more patients dropped out of voice therapy than the ones completed the therapy. They showed only 35.4% of the 147 participants completed the therapy and 64.6% dropped out. And there was no significant difference between the ones who completed the therapy and the ones who dropped out on the demographic variables (gender, age, and race/ethnicity) [13]. Smith et al. also showed a high percentage of patients (44%) who essentially did not attend the therapy [14]. Our data support high percentage of nonattendance to voice therapy too.

CONCLUSIONThis study is the first of its kind which analyzes the

demographic features, the diagnoses of voice therapy patients in Turkey and patient’s attendance to therapy. Most of the patients were referred by ENT doctors. Adults were directed more frequently than children. The frequent diagnoses of patients who

were referred for voice therapy were nodules and functional dysphonia in Turkey. It is observed that there is a high percentage of nonattendance to voice therapy sessions. Future research may examine the causes of low referrals of pediatric patients to voice therapy and the reasons of dropouts of therapy sessions. It is offerable to improve the awareness about vocal hygiene, voice health, voice disorders and therapy for raising the endurance to voice therapy.

ACKNOWLEDGEMENTSThis article is dedicated to Prof. Saime Seyhun Topbaş for her

part in establishing the first Education, Research and Training Centre for Language and Speech Disorders in Turkey.

We acknowledge Mr. Elkhan Abbasov for his assistance in estimating the data in this study.

The data of the study were presented in the 8th National Audiology and Speech Disorders Congress.

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Abbasova A, Ozkan ET (2018) Features of Voice Therapy Patients of the Education, Research and Training Centre for Language and Speech Disorders in Turkey. Ann Otolaryngol Rhinol 5(2): 1206.

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