Laryngology
Published: 2018-10-01
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Relationship between socio-demographic characteristics and vocal fold nodules, polyps and oedema

Faculty of Medicine, University of Belgrade, Serbia; Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia
Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia
Faculty of Medicine, University of Belgrade, Serbia; Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia
Institute of Epidemiology, Faculty of Medicine, University of Belgrade, Serbia
Faculty of Medicine, University of Belgrade, Serbia; Clinic for Physical Medicine and Rehabilitation, Clinical Centre of Serbia, Belgrade, Serbia
Faculty of Medicine, University of Belgrade, Serbia; Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia
Center for Radiology and Magnetic Resonance Imaging, Clinical Centre of Serbia, Belgrade, Serbia
Institute of Epidemiology, Faculty of Medicine, University of Belgrade, Serbia
Vocal fold nodules Polyps Edema Epidemiological study

Abstract

The aim of our study was to compare socio-demographic characteristics of vocal fold nodules, polyps and oedema. The study included patients di- agnosed for the first time with vocal fold nodules, polyps and oedema at the Communication Disorders Care Center of Clinic for Otorhinolaryngol- ogy and Maxillofacial Surgery in Clinical Center of Serbia, Belgrade. Diagnosis was made on the basis of symptoms, clinical otorhinolaryngologi- cal and phoniatric examination and endovideolaryngostroboscopic findings. A self-administered questionnaire was used to collect the following data: socio-demographic status, exposure to occupational noise and air pollution, occupational voice demands, health habits, symptoms of the present voice problems and voice problems in the family. By multivariate logistic regression analyses, nodules and oedema were more frequent in women than men in comparison with polyps (p < 0.001). Patients with nodules and polyps were younger than those with oedema (p < 0.001). Pa- tients with nodules were more frequently lecturers, singers and actors compared with polyp patients (p = 0.006), had occupational voice demands more frequently than patients with oedema (p = 0.037) and were less frequently smokers than patients with polyps (p = 0.043) and those with oedema (p < 0.001). Patients with oedema were more frequently current smokers than patients with nodules and those with polyps (p < 0.001). Hoarseness as the main symptom was more frequent among patients with nodules than among patients with polyps (p = 0.040) and those with oedema (p = 0.001).Voice problems in the family was more frequently reported by oedema patients than by patients with polyps (p = 0.005). These findings are in agreement with majority of previous studies and may be of help in investigations on the aetiology of the disease.

Introduction

Vocal fold nodules, polyps and oedema are classified as vocal fold masses, also known as exudation lesions of Reinke space 1 2. The aetiology, pathogenesis, histology and clinical aspects of these lesions are still rather controversial, as well as their management.

It has been considered that both genetic and environmental factors play a role in the development of vocal fold (VF) disease 3 4. Gender, age, education level, occupations, vocal abuse or misuse, cigarette smoking, alcohol consumption, unfavourable microclimate conditions at work and comorbidities such as gastro-oesophageal reflux, infections, allergy and thyroid diseases are recongised risk factors 5-13.

Investigations of factors related to VF nodules, polyps and oedema show some differences between these three forms of VF disease. For example, in the study by Nagata et al. 5 polyps were frequent in middle-aged subjects of both sexes, whereas nodules were more common in boys and middle-aged women. Smoking was more frequently associated with VF oedema than with nodules and polyps 7. These and similar findings raised the question of whether VF nodules, polyps and oedema were the same entity. Although only genetic studies and studies at molecular level might definitively answer the question, it is of help to understand the main differences among VF nodules, polyps and oedema in terms of socio-demographic characteristics.

The aim of our study was to compare the socio-demographic characteristics of vocal fold nodules, polyps and oedema.

Materials and methods

The study included patients diagnosed for the first time with VF nodules, polyps and oedema at the Communication Disorders Care Center of Clinic for Otorhinolaryngology and Maxillofacial Surgery in Clinical Center of Serbia, Belgrade, during October 2014 - March 2015.

Diagnosis was made on the basis of symptoms, clinical otorhinolaryngological and phoniatric examination and endovideolaryngostroboscopic findings. The diagnosis was established by multidisciplinary team consisted of two phoniatricians, two laryngologists and two logopaedics with at least 20 years of experience in the field of communication disorders. Endovideolaryngostroboscopy was a key tool because it allows all members of the team to take a part in examination at the same time. Inclusion criteria were age over 18 years and voluntary participation. Exclusion criteria were neurological and psychiatric illness, malignant disease, severe hearing loss, transsexual conflict, professional voice needing urgent phonosurgery and no treated comorbidities (reflux, allergy, thyroid end lung disease).

Using a self-administered questionnaire, the following data were collected: gender, age, height and weight, marital status, educational level, occupation, working experience, exposure to occupational noise and air pollution, additional job, occupational voice demands, family income, physical activity, cigarette smoking, alcohol consumption, comorbidity, symptoms of present voice problems and duration in months and voice problems in the family. Body mass index (BMI) was calculated as weight (kg) divided by height (m2). With reference to smoking, each patient was classified as a nonsmoker, former smoker or current smoker. A current smoker was defined as a person who smoked at least one cigarette per day in the 12 months before the disease or who quit smoking within that year. A former smoker was defined as a person who quit for more than a year before the disease occurrence. Regarding alcohol consumption, patients were divided into two groups: ever drinkers and non-drinkers (those who during their life drank less than 12 alcoholic beverages) 14. Physical activity comprised any kind of unprofessional physical activity for 30 min per day during the previous month. Persons who exercised more than once a week were considered physically active and the others physically inactive.

For statistical analysis univariate and multivariate logistic regression methods were used. All test variables with statistical significance of p ≤ 0.10 in the univariate model were included in the multivariate model. Significance was considered with a p value < 0.05. Statistical analysis was performed using the SPSS 20 package.

Results

Of 205 patients with exudative lesions of Reinke’s space, 72 (35.12%) were with nodules, 70 (34.14%) with polyps and 63 (30.63%) with oedema.

Characteristics of patients with nodules, polyps and oedema, and differences between these three groups according to univariate logistic regression analysis, are presented in Tables I-III.

When compared with VF polyp patients, those with VF nodules were significantly more frequent in women, younger, not married and with university education. In comparison with VF oedema patients, those with VF nodules were significantly younger, not married, with university education and with high family income. Patients with VF polyps, compared with VF oedema patients, were significantly more frequent in younger men (Table I).

According to data in Table II, patients with VF nodules, compared with VF polyps, significantly differed in occupation, had significantly shorter working experience, were significantly more exposed to noise in the working place and more frequently with considerable and immense occupational voice demands.

In comparison with VF oedema patients, VF nodule patients also significantly differed in occupation, had significantly shorter working experience and were significantly more frequent in patients with considerable and immense voice demands.

Patients with polyps and those with VF oedema significantly differed only in the working experience, which was shorter in patients with VF polyps.

Table III shows health habits, body mass index, and data from personal and family history of patients with nodules, polyps and oedema.

Patients with VF nodules and those with VF polyps significantly differed only in smoking and BMI. Ever smoking and current smoking were more frequent among patients with VF polyps, who also were more frequently overweight and obese.

According to comparison with VF nodule patients, those with VF oedema were significantly more frequently ever smokers and current smokers, were less frequently physically active and more frequently overweight and obese. They also had hoarseness less frequently as the main presenting symptom and longer duration of symptoms before visiting physician. Altogether other diseases were more frequent among oedema patients, but single disease, allergy, reflux and thyroid diseases were more frequent among VF nodule patients, and cardiovascular diseases among VF oedema patients.

In comparison with VF polyp patients, those with VF oedema were significantly more frequent in ever smokers and current smokers, were less frequently physically active, had less frequently hoarseness as the main symptom and had longer duration of symptoms before visiting a physician. Patients with VF oedema significantly more frequently reported family history positive on voice problems.

Variables with statistical significance of p ≤ 0.10 according to univariate analysis were included in multivariate analysis. According to multivariate logistic regression analyses (Table IV) there were significant differences between groups for several characteristics. Patients with nodules and oedema were more frequent in women than men in comparison with polyp patients (p < 0.001). Patients with nodules and polyps were younger than oedema patients (p < 0.001). Patients with nodules were more frequently lecturers, singers and actors compared with polyp patients (p = 0.006), had occupational voice demands (considerable and immense) more frequently than patients with oedema (p = 0.037) and were less frequently smokers than patients with polyps (p = 0.043) and those with oedema (p < 0.001). Patients with oedema were more frequently current smokers than patients with nodules and those with polyps (p < 0.001). Hoarseness as the main symptom of the present disease was more frequent among patients with nodules than among patients with polyps (p = 0.040) and those with oedema (p = 0.001). Voice problems in the family were more frequently reported by oedema patients than by those with polyps (p = 0.005).

Discussion

It is still a paradigm how to classify vocal fold nodules, polyps and edema 15. Although it seems reasonable to place all of the three together, there are some differences between them. In the present study, patients with nodules, polyps and oedema significantly differed in seven characteristics: gender, age, occupation, occupational voice demands, smoking, family history of voice problems and symptoms.

Age and gender related risks for specific voice disorders have been highlighted by other authors 16 17. In our investigation, the three groups were strictly divided. VF nodule patients were predominantly at the age of 40 and under, and VF oedema patients at the age of 41 and over. The VF polyps group was more balanced, with 32 patients with an age of 40 and under, and 38 patients with an age of 41 and over. In the investigation by Yoon Se Lee et al. 18 the age range for vocal fold polyps in the group of 41 males and 51 females was 22-72 years, with an average of 51. The reasons for this age distribution are still not clear, but from a socio-demographic point of view it seems that VF nodules are a disease of the young, and that VF oedema is a disease of an older population because of large differences in vocal and health behaviour of these two groups.

In our investigation, in the VF polyps group 52.9% of patients were men, compared to only 4.2% in the VF nodules group and 11.1% in the VF oedema group. This gender difference may be related to many factors, both genetic and psychological, but also with environmental factors 3.

It would seem that gender and age are of importance in determination in which direction one exudative lesion of Reinke’s space will develop. Women with vocal folds in the presence of risk factors will develop nodules rather than polyps. Older women with vocal folds in the presence of risk factors will develop oedema rather than polyps. The reasons for this are still unclear, probably lying at the molecular level, and likely associated with contributing factors such as occupational voice demands, smoking and delay of seeking medicine attention.

The type of occupation has also been recognised as a risk factor for VF disease 8. In fact, the type of occupation is related to voice demands and air pollution. The incidence of vocal fold nodules and polyps correlates with vocal overuse 19. Increased vocal use, predominantly linked to the VF polyps group, was connected with professions such as army and police commanders, street and other sale persons, receptionists, medical stuff and speech and language therapists, lawyers, judges, hair dressers. Considerable vocal use, mostly linked to VF nodules group, was registered in teaching stuff, telephone operators, clerks, politicians, sport trainer and managers. For example, in a study from Spain, the prevalence of voice disorders among teachers was 14% for nodular lesions, 2% for polyps and 1.2% for Reinke’s oedema 20. In the study conduted by Krecicki et al. 8, women formed the majority, and teachers formed the largest occupational group (30%). Immense vocal use, also linked to the VF nodules group, is present in singers, actors, TV and radio speakers and showmen 19. In our investigation, VF nodules were linked to voice overuse (considerable and immense occupational voice demands). Alvarez also found that voice abuse or misuse was the main factor in patients with VF nodules 21.

There is general acceptance of a close relationship between chronic cigarette smoke exposure and onset of voice pathology, especially Reinke’s oedema 7. In the study by Krecicki et al. 8 most VF oedema patients (86%) were smokers. According to the investigation by Alvarez et al. 21 smoking was the main symptom in polyps and oedema. In our study, smokers were most frequent among VF oedema patients. Up to 98.4% of patients with oedema were ever smokers, and 85.7% were current smokers. Among patients with VF polyps, 70.0% were smokers (37.1% current smokers), which was less than among patients with oedema but more than among those with nodules. However, there are few basic investigations on this subject, and the existing studies do not give firm evidence about the effects of smoking on formation of vocal fold oedema 22 23.

In the present study, family history positive for vocal problems was reported by 11.4% to 28.6% patients, and was most frequent in oedema patients. It has been considered that genetic factors play role in the development of VF nodules, polyps and oedema 3 4. There is a possibility that various genes are associated with each of VF disorders – nodules, polyps, edema – and that their expression is influenced by various environmental factors. However, there is also possibility of recall differences between compared groups.

In patients with VF oedema, symptoms other than hoarseness were more frequent (39.7%) than in the other two groups of patients. This can be explained since in a large number of patients with oedema, symptoms lasted more than 12 months before they visited a physician.

In summary, on the basis of mutual comparisons of patients with VF nodules, polyps and oedema, the main characteristics of these three types of vocal fold were as follows: patients with nodules were most frequently women ≤ 40 years old, with a high-risk occupation (lecturer, singer, actor), with considerable and intensive occupational voice demands, with a similar proportion of ever smokers and non-smokers, and hoarseness as a dominant symptom; patients with polyps were almost equally distributed by gender and age, were most frequently administrative workers, frequently ever smokers and current smokers and had hoarseness as a dominant symptom; patients with oedema were most frequently women 41 or more years old, without or with slightly increased occupational voice demands, almost all were ever smokers and large proportion were current smokers, more than a quarter of them had positive family history on voice problems, and a considerable number had symptoms other than hoarseness.

Besides limitations related to collection of data by the use of the questionnaire, the main limitation is the relatively small number of patients.

Conclusions

Mutual comparisons of patients with VF nodules, polyps and oedema showed that they differed in several main characteristics. These findings are in agreement with the majority of existing studies and may be of help in future investigations on the aetiology of the disease.

Conflict of interest statement

None declared.

Figures and tables

Variable Patients with p value * for
VF nodules (n = 72) VF polyps (n = 70) VF oedema (n = 63) VF nodules vs VF polyps VF nodules vs VF oedema VF polyps vs VF oedema
N (%) N (%) N (%)
GenderMaleFemale 3 (4.2)69 (95.8) 37 (52.9)33 (47.1) 7 (11.1)56 (88.9) < 0.001 0.139 < 0.001
Age (years)≤ 40> 40 55 (76.4)17 (23.6) 32 (45.7)38 (54.3) 6 (9.5)57 (90.5) < 0.001 < 0.001 < 0.001
Married 37 (51.4) 53 (75.7) 46 (73.0) 0.003 0.011 0.722
EducationElementary to high schoolFaculty 34 (47.2)38 (52.8) 45 (64.3)25 (35.7) 47 (74.6)16 (25.4) 0.042 0.010 0.200
IncomeLowMiddleHigh 1 (1.4)38 (52.8)33 (45.8) 2 (2.9)45 (64.3)23 (32.9) 3 (4.8)41 (65.1)19 (30.2) 0.104 0.042 0.614
Table I.Socio-demographic characteristics of patients with vocal fold nodules, polyps and oedema.
Variable Patients with p value * for
VF nodules (n = 72) VF polyps (n = 70) VF oedema (n = 63) VF nodules vs VF polyps VF nodules vs VF oedema VF polyps vs VF oedema
N (%) N (%) N (%)
Type of occupationSinger, ActorLecturerPhysical workerAdministrative workerHealth workerUnemployedRetired 9 (12.5)20 (27.8)3 (4.2)23 (31.9)6 (8.3)9 (12.5)2 (2.8) 3 (4.3)4 (5.7)7 (10.0)40 (57.1)5 (7.2)3 (4.3)8 (11.4) 2 (3.2)4 (6.3)11 (17.5)23 (36.5)3 (4.8)1 (1.6)19 (30.2) 0.003 0.044 0.238
Working experience (years)< 20≥ 20 51 (81.0)12 (19.0) 39 (58.2)28 (41.8) 16 (25.8)46 (74.2) 0.006 < 0.001 < 0.001
Has additional job 27 (37.5) 20 (28.4) 19 (30.2) 0.259 0.370 0.841
Noise in the working place 49 (68.1) 35 (50.0) 34 (54.0) 0.030 0.095 0648
Polluted air in the working place 36 (50.0) 35 (50.0) 30 (47.6) 0.782 1.000 0.784
Occupational voice demandsNoIncreasedConsiderableImmense 18 (25.0)17 (23.6)25 (34.7)12 (16.7) 28 (40.0)26 (37.1)12 (17.1)4 (5.7) 35 (55.5)19 (30.2)7 (11.1)2 (3.2) 0.002 < 0.001 0.078
Table II.Type of occupation, occupational conditions and professional voice use in patients with vocal fold nodules, polyps and edema.
Variable Patients with p value * for
VF nodules (n = 72) VF polyps (n = 70) VF oedema (n = 63) VF nodules vs VF polyps VF nodules vs VF oedema VF polyps vs VF oedema
N (%) N (%) N (%)
Smoking statusNon smokerFormer smokerCurrent smoker 35 (48.6)21 (29.2)16 (22.2) 21 (30.0)23 (32.9)26 (37.1) 1 (1.6)8 (12.7)54 (85.7) 0.017 < 0.001 0.002
Alcohol consumption 18 (25.0) 27 (38.6) 16 (25.4) 0.084 0.958 0.107
Physically active (recreation) 56 (77.8) 50 (71.4) 32 (50.8) 0.386 0.001 0.015
Body mass indexNormal weightOverweight or obese 56 (77.8)16 (22.2) 35 (50.0)35 (50.0) 27 (42.9)36 (57.1) 0.001 < 0.001 0.847
Present disease symptomsHoarsenessDyspneaOther 62 (86.1)1 (1.4)9 (12.5) 55 (78.6)1 (1.4)14 (20.0) 38 (60.3)3 (4.8)22 (34.9) 0.229 0.001 0.033
Duration of symptoms (months)≤ 12> 12 60 (83.30)12 (16.7) 50 (71.4)20 (28.6) 29 (46.0)34 (54.0) 0.093 < 0.001 0.003
Has some other diseases 36 (50.0) 41 (58.6) 45 (71.9) 0.306 0.012 0.123
Type of other diseaseAllergyRefluxThyroidCardiovascularOther 7 (19.4)10 (27.8)7 (19.4)5 (13.9)7 (19.4) 5 (12.2)12 (29.3)7 (17.1)7 (17.1)10 (24.4) 3 (6.7)6 (13.3)8 (17.6)17 (37.8)11 (24.4) 0.414 0.016 0.093
Voice problems in the family 11 (15.3) 8 (11.4) 18 (28.6) 0.502 0.064 0.016
Table III.Smoking, alcohol consumption, recreational physical activity, body mass index, and personal and family history of patients with vocal fold nodules, polyps and oedema.
Variable VF nodule patients vs VF polyp patients VF nodule patients vs VF oedema patients VF polyp patients vs VF oedema patients
OR (95% CI) p value OR (95% CI) p value OR (95% CI) p value
Gender (women/ men) 30.30(8.13-111.11) p < 0.001. 0.07(0.02-0.24) < 0.001
Age (≤ 40 years/> 40 years) 14.03(3.58-54.92) p < 0.001 17.27(4.36-68.36) < 0.001
Occupation * 2.50(1.30-4.76) 0.006
Occupational voice demands 2.04(1.04-4.0) 0.037
Smoker (no; former; current) 0.59(90.35-0.98) 0.043 0.15(0.06-0.37) < 0.001 0.19(0.08-0.43). < 0.001
Symptoms of the present disease(hoarseness/dyspnoea and others) 2.93(1.05-8.20) 0.040 13.49(2.75-66.15) 0.001
Voice problems in the family (yes/no) 0.13(0.03-0.53) 0.005
Table IV.Characteristics which significantly differed between patients with vocal fold nodules, polyps and oedema, according to multivariate logistic regression analysis.

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Affiliations

J. MILOVANOVIC

Faculty of Medicine, University of Belgrade, Serbia; Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia

M. VUKASINOVIC

Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia

A. JOTIC

Faculty of Medicine, University of Belgrade, Serbia; Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia

H. VLAJINAC

Institute of Epidemiology, Faculty of Medicine, University of Belgrade, Serbia

A. MILOVANOVIC

Faculty of Medicine, University of Belgrade, Serbia; Clinic for Physical Medicine and Rehabilitation, Clinical Centre of Serbia, Belgrade, Serbia

B. PAVLOVIC

Faculty of Medicine, University of Belgrade, Serbia; Clinic for Otorhinolaryngology and Maxillofacial Surgery, Clinical Centre of Serbia, Belgrade, Serbia

B. BANKO

Center for Radiology and Magnetic Resonance Imaging, Clinical Centre of Serbia, Belgrade, Serbia

J. MAKSIMOVIC

Institute of Epidemiology, Faculty of Medicine, University of Belgrade, Serbia

Copyright

© Società Italiana di Otorinolaringoiatria e chirurgia cervico facciale , 2018

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