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Received: 22 December 2021 / Accepted: 15 April 2022 / Published online: 30 April 2022
DOI 10.34689/SH.2022.24.2.007 UDC 616-053.2-28-002
RISK FACTORS OF HEARING IMPAIRMENT IN PEDIATRIC PATIENTS WITH CHRONIC OTITIS MEDIA
Timur Shamshudinov1*, Saule Taukeleva2
1 City Center of Pediatric Otorhinolaryngology, General Hospital №5, Almaty, Republic of Kazakhstan;
2 Kazakh-Russian Medical University, Almaty, Republic of Kazakhstan.
Summary
Introduction. Chronic otitis media (COM) is one of the most common disorders in pediatric practice. The burden of the disease in industrialized countries is associated with hearing loss and further developmental delay in the child. COM is most often associated with a conductive type of hearing impairment since bone elements of the auditory chain undergo destruction due to the chronic purulent inflammation.
Objective: The aim of our study is the identification of risk factors in pathogenesis if COM for the possible development of effective preventive measurements.
Materials and methods: The current study presents the analysis of personal data and medical records using the descriptive and regression statistics. Sixty-five pediatric patients with chronic otitis media were enrolled. The study was conducted otorhinolaryngological department of the City Clinical Hospital No. 5 of the Health Department of Almaty in the period from March 2018 to March 2020.
Results and conclusions. The results of our investigation demonstrated that some prevalent characteristics of paediatric patients with chronic otitis media may act as possible risk factors for the impairment of hearing function. Thus, the avoiding of acute inflammatory middle ear diseases and total cancelling of treatment with ethanol containing ear drops may contribute greatly in the prevention of hearing loss and impairment. Key words: chronic otitis media, risk factors, hearing loss.
Резюме
ФАКТОРЫ РИСКА СНИЖЕНИЯ СЛУХОВОЙ ФУНКЦИИ У ДЕТЕЙ С ХРОНИЧЕСКИМ СРЕДНИМ ОТИТОМ
Тимур Шамшудинов1*, Сауле Таукелева2
1 Городской центр детской оториноларингологии, Городская клиническая больница №5, г. Алматы, Республика Казахстан;
2 Казахстано-Российский Медицинский Университет, г. Алматы, Республика Казахстан.
Введение. Хронический средний отит (ХСО) является одним из наиболее распространенных заболеваний в педиатрической практике. Бремя болезни в индустриально развитых странах связано с потерей слуха и дальнейшей задержкой развития ребенка. ХСО чаще всего сочетается с кондуктивным типом тугоухости, так как костные элементы слуховой цепи подвергаются деструкции вследствие хронического гнойного воспаления.
Целью нашего исследования является выявление факторов риска в патогенезе ХСО для последующей разработки эффективных профилактических мероприятий.
Материалы и методы. В настоящем исследовании представлен анализ персональных данных и медицинских карт с использованием описательной и регрессионной статистики. В исследование было включено 65 детей с хроническим средним отитом. Исследование проводилось в оториноларингологическом отделении Городской клинической больницы №5 Департамента здравоохранения города Алматы в период с марта 2018 года по март 2020 года.
Результаты и выводы. Результаты нашего исследования показали, что некоторые наиболее распространенные характеристики детей с хроническим средним отитом могут выступать в качестве возможных факторов риска нарушения функции слуха. Таким образом, предотвращение острых воспалительных заболеваний среднего уха и полная отмена лечения ушными каплями, содержащими этанол, могут в значительной степени способствовать профилактике потери и нарушений слуха.
Ключевые слова: хронический средний отит, факторы риска, потеря слуха.
Тушндеме
СОЗЫЛМАЛЫ ОРТА ОТИТКЕ ШАЛДЫККАН БАЛА ЖАСЫНДАГЫ НАУКАСТАРДЫИ ЕСТУ КАБ1ЛЕТ1Н1Н Т0МЕНДЕУ ФАКТОРЛАРЫ
Тимур Шамшудинов1*, Сауле Таукелева2
1 Бала оториноларингологиясыньщ калалык орталыгы, №5 Калалык клиникалык емхана, Алматы к., Казакстан Республикасы;
2 Казакстан-Ресей Медициналык Университетi, Алматы к., Казакстан Республикасы.
Kipicne. Созылмалы орта кулак отит (СОО) педиатриялык т8жiрибеде жиi кездесетiн аурулардыч 6ipi болып табылады. Индустриалды дамыган елдердеп аурудыч ауыртпалыгы есту кабiлетiнiк жогалуымен ж8не баланыч дамуыныч одан 8рi кешiгуiмен байланысты. СОО Ke6ÍHece есту кабтетУч жогалуыныч вткiзгiш тYрiмен бiрiктiрiледi, вйткенi есту тiзбегiнiи сYЙек элементтерi созылмалы iрiчдi кабыну салдарынан жойылады.
Максаты. Бiздiи зерттеуiмiздiн максаты келешектеп тиiмдi алдын алу шараларын 8зiрлеу Yшiн СОО патогенезiндегi кауiп факторларын аныктау болып табылады.
Материалдар мен тэсшдер. Бул зерттеу сипаттамалык ж8не регрессиялык статистиканы пайдалана отырып, жеке деректер мен медициналык жазбалардыч талдауын усынады. Зерттеуге созылмалы орта кулак отитiмен ауыратын 65 бала катысты. Зерттеу Алматы каласы Денсаулык сактау баскармасыныч №5 калалык клиникалык ауруханасыныч оториноларингология бвлiмшесiнде 2018 жылдыч наурыз айынан 2020 жылдыч наурыз айына дейiн жYргiзiлдi.
Нэтижелер мен корытындылар. Бiздiи зерттеуiмiздiн н8тижелерi созылмалы орта кулак отитi бар балалардыч еч жиi кездесетiн кейбiр сипаттамалары есту кабтетУч жогалуыныч ыктимал кауiп факторлары ретiнде 8рекет етуi мYмкiн екеын кврсеттi. Осылайша, ортачгы кулактыч жедел кабыну ауруларыныч алдын алу ж8не курамында этанол бар кулак тамшыларымен емдеудi толыгымен токтату есту кабтетУч жогалуы мен нашарлауыныч алдын алуга Yлкен ыкпал етедi.
TYÜiHdi свздер: созылмалы отит медиасы, к,ау'т факторлары, есту цабшетшщ жогалуы.
Bibliographic citation:
Shamshudinov T., Taukeleva S. Risk factors of hearing impairment in pediatric patients with chronic otitis media // Nauka iZdravookhranenie [Science & Healthcare]. 2022, (Vol.24) 2, pp. 57-62. doi 10.34689/SH.2022.24.2.007
Шамшудинов Т., Таукелева С. Факторы риска снижения слуховой функции у детей с хроническим средним отитом // Наука и Здравоохранение. 2022. 2(Т.24). С. 57-62. doi 10.34689/SH.2022.24.2.007
Шамшудинов Т., Таукелева С. Созылмалы орта отитке шалдыккан бала жасындагы наукастардыч есту КабтетУч темендеу факторлары // Гылым жэне Денсаулык сактау. 2022. 2 (Т.24). Б. 57-62. doi 10.34689/SH.2022.24.2.007
Introduction
Chronic otitis media (COM) is one of the most common disorders in pediatric practice. Annually about thirty million patients seek for medical service because of the inflammation of the middle ear. Since the diagnostic and classification approaches in definition of the disease vary throughout the world the prevalence of COM in the world ranges from 65 to 330 million cases per year [4]. The burden of the disease in industrialized countries is associated with hearing loss and further developmental delay in the child. In developing countries, the problem of COM is strongly correlated with deaths and severe complications leading to disability Exacerbations of COM may lead to the antibiotic resistance, deterioration in the quality of life of children and their parents. The economic losses linked with the management of the disease and temporary disability of parents due to the opening of sick leave to care for a child [11].
Obviously, COM is most often associated with a conductive type of hearing impairment since bone elements of the auditory chain undergo destruction due to the chronic purulent inflammation. However, the constant presence of
pathogenic flora in the middle ear cavity promotes the absorption of microbial toxins and macromolecules that can affect the structures of the inner ear, leading to the development of sensorineural hearing loss [2]. Intracranial complications of COM can lead to the development of deafness in 10% of patients [13].
Conceptually, the main trigger in the pathogenesis of COM is the acute inflammation of the middle ear. In the majority of cases the acute otitis media becomes a complication of the respiratory infections, manifested clinically by inflammation of the pharynx with damage of the Eustachian tube's mucous membrane. The defeat of the Eustachian tube (ET) is accompanied by a violation of the cycle of opening and closing of the pharyngeal opening, which leads to a decrease in pressure in the middle ear cavity and, as a result, aspiration of pathogenic bacteria from the nasopharynx. In addition, the viral infection itself provokes inhibition of the function of ET clearance, which is expressed in a decrease in mucus secretion in goblet cells and a slowdown in the sweeping movements of ciliated cells. Viruses can also promote the expression of certain molecules of the mucosal cell wall as additional co-
receptors of pathogenic bacteria [3, 9]. Another hallmark of COM is the development of mucositis, which is characterized by a hyperplastic process in the mucous membrane and excessive production of exudate. The mucositis itself is formed from biofilm - a structure consisting of microbial cell wall polysaccharides, fibrin and mucins of the macroorganism [5].
In most cases, the disease develops in early childhood, most often during the first two years of life. When clarifying the details of the anamnesis of life and disease, it is possible to identify such risk factors for the development of chronic otitis media as frequent episodes of acute otitis media, upper respiratory tract infections, trauma to the eardrum, and nutritional deficiencies [15]. Other causes associated with the development of COM are pathological conditions that affect the functionality of the auditory tube -congenital anomalies of the facial skeleton and diseases of the pharynx. One of the significant risk factors for the development of pathology is the low level of income in the family in which the child was born and grows [18].
The understanding and considering all risk factors for the development of inflammation of the middle ear and chronicity of the process make it possible to create a successful tactic for the management and treatment of patients with childhood COM. Thus, the aim of our study is the identification of risk factors in pathogenesis if COM for the possible development of effective preventive measurements.
Materials and methods
Enrollment of the participants in the study took place among patients hospitalized in the otorhinolaryngological department of the City Clinical Hospital No. 5 of the Health Department of Almaty in the period from March 2018 to March 2020. The inclusion criteria for the study were the following characteristics of patients: verified diagnoses of chronic otitis media with the concurrent adenoid hypertrophy (ICD10 codes - H66.1 Chronic perforated otitis media; J35.2 Adenoid hypertrophy grades 2-3); age <18 years; availability of informed consent of children and/or their parents or guardians. Children whose parents or guardians refused to participate in the study were excluded from the sample. The study was approved by the Ethics Committee of Kazakh medical university of continuing education (Protocol no.: 1, from January 15, 2019), and the research was conducted in compliance with principles of the Declaration of Helsinki and the Guideline for Good Clinical Practice.
For the collection of collect personal data and medical information, a clinical register of the study participant was developed. The register was filled in by copying information from the outpatient records and the patient's medical history. The missing data was obtained during a face-to-face meeting, telephone conversation, correspondence via mobile messengers or e-mail.
The clinical register was developed by the author of the study and includes the following sections:
1) passport data;
2) data on the antenatal period of development;
3) data on the characteristics of breastfeeding;
4) development of the child from birth to 12 months;
5) history of respiratory disorders;
6) history of hearing impairment;
7) otosurgical features;
8) nasopharyngeal surgery;
9) early and late postoperative periods.
The last part - the results of tone threshold audiometry (measurement of the air-bone interval) and otoendoscopy (anatomical integrity of the neotympanic membrane) - was filled out during repeated control examinations after 1, 3, 6, 12 months from the date of the surgical intervention.
Statistical analysis
The R 3.6.3 software (R Foundation for Statistical Computing, Vienne, Austria) was used for statistical analyses. Descriptive statistics for categorical variables are presented as absolute and relative frequencies (percentages, %), for quantitative ones - as medians (1st and 3rd quartiles) and mean (standard deviation).
The Mann-Whitney test was used to compare quantitative variables. Fisher's exact test was used to analyze the association between categorical variables. Regression analyses were carried out: dependent variable - air-bone gap; independent variables - different parameters from personal and medical records. A p-value <0.05 was defined as statistically significant.
Results
For the identification of risk factors of hearing loss 65 pediatric patients with chronic otitis media in combination with adenoid hypertrophy receiving the surgical treatment were enrolled within 2 years. The age median of sample was 9,42 (5,73-12,22). The males: females' ratio was equal to 1,24 (36 boys and 29 girls).
Table 1 demonstrates the health condition of maternal health condition, the details of history of delivery and feeding. On third of mothers had some somatic pathologies, and every fifth female was affected with the disorder of reproductive system. The vast majority of children were born in term, but only half of them were fed with breast milk. Only 4% of participants were feeding in vertical position.
Table 1.
The history of pregnancy and breast feeding (n=65).
Variables N %
Extragenital pathology of mother 19 29,23
Genital pathology of mother 13 20,0
Delivery Natural 50 76,92
Caesarean section 15 23,08
Delivery time In term 56 86,15
Premature delivery 9 13,85
Child feeding Breast 35 53,84
Bottle-feeding 5 7,69
Mixed 25 38,47
Feeding position Vertical 3 4,62
Horizontal 22 33,85
Mixed 40 61,53
Also, we checked the prevalence of possible risk factors within the first year of life (Table 2). About one third of children had the allergy in their history. The overwhelming majority of patients were vaccinated according to the Kazakhstani national vaccination calendar. More than half of participants suffered from exudative otitis. The quarter of patients had the relatives with the hearing impairment. About 80% of children were treated with ethanol-containing ear drops.
Table 2.
First 12 months of life and history of ENT disorders.
Variables N %
History of allergic conditions and diseases 23 35,39
Vaccination on schedule 54 83,08
Family history of hearing impairment 19 29,23
Episodes of impaired breath 29 44,62
History of acute otitis media 16 24,62
Episodes of otorrhea 38 58,46
Use of ethanol containing ear drops 51 78,46
Table 3 shows the condition of nose, throat and the presence of adenoid hypertrophy. Every third patient had the II degree of disease. Approximately half of the patients suffered from sleep obstructive apnea syndrome. It seems obvious that some patients had the ENT comorbidities. About half of children had the 1-3 months history of sinusitis of different locations.
Table 3.
History of upper airways pathology.
Variables N %
Degree of adenoid hypertrophy I degree 10 15,38
II degree 21 32,31
III degree 10 15,38
II degree + choanal syndrome 13 20,0
III degree + choanal syndrome 11 16,93
Sleep obstructive apnea syndrome 31 47,69
Pharmacological treatment of sinusutis 49 75,38
Local intranasal glucocorticosteroids 26 40,0
History of sinusitis 1 month 19 29,23
1-3 months 32 49,23
3-6 months 9 13,84
More than 3 months 5 7,7
About 60% of patients suffered from COM more than 3 years. The ration of participants with one sided and two-sided forms of disease was 1:1. More than 60% of children were treated with systemic and local antibiotics. Two thirds of patients had the experience of exposure to ethanol-containing ear drops. The median of air-bone gap was equal to 43,48 (38,03-51,97) dB. According to computer tomography half of the children had the sclerotic type of pneumatization of temporal bone Table 4.
Table 5 contains the analysis of possible risk factors of hearing impairment. In this case the linear regression method was used. It allows to evaluate the impact of several qualitative parameters on the air-bone gap variable. The significant increase of air-bone gap was associated with the previous history of acute otitis media, the episodes of otorrhea, and the treatment with ethanol-containing ear drops.
Table 4.
History of chronic otitis media and hearing impairment.
Variables N %
1-3 months 4 6,15
History of COM 3-12 months 4 6,15
1-3 years 17 26,15
More than 3 years 40 61,55
Affected side One sided 36 55,38
Two sided 29 44,62
Exacerbation of otitis Less than 1 month 1 1,54
prior to surgery as 1-3 months 17 26,15
an otorrhea More than 3 months 47 72,31
No exacerbations 1 1,54
Frequency of exacerbations From 1 to 3 times per year 42 64,62
More than 3 times per year 22 33,84
ENT* interventions
Systemic antibiotics 64 98,46
Inhaled forms of 38 58,46
Pharmacological treatment glucocorticoids
Local antibiotics 62 95,38
Local corticosteroids 47 72,31
Ethanol containing ear drops 61 93,85
Conducting hearing loss, bilateral (H.90) 35 53,85
Conductive hearing loss, unilateral with
Type of hearing impairment unrestricted hearing on the contralateral side 29 44,61
according to ICD-10 (H90.1)
before the surgery Mixed conductive and
sensorineural hearing loss, unilateral with 1 1,54
unrestricted hearing on the contralateral side
(H90.7)
Air-bone gap, dB
(median (1st and 3rd quartiles) 43,48 (38,03-51,97)
Good pneumatization 19 29,23
Computer Sclerotic type of pneumatization 32 49,23
tomography Loss of pneumatization 13 20,0
Pathological lesions 1 1,54
Remission period of COM before the Less than 1 month 9 13,85
1-3 months 25 38,46
surgery More than 3 months 35 53,84
*Ear, Nose, Throat
Table 5.
Factors affecting the air-bone gap parameter._
Variable ß [95% CI] P* р**
Male gender 1.3 [-3.5; 6.0] 0.5966
Extragenital pathology -1.6 [-6.8; 3.6] 0.5320
Genital pathology 5.2 [-0.6; 11.0] 0.0773
Caesarean section 1.1 [-4.5; 6.7] 0.6893
Premature delivery 1.2 [-5.6; 8.1] 0.7213
Child feeding Bottle-feeding 7.7 [-1.3; 16.7] 0.0930 0.2152
Mixed -0.2 [-5.1; 4.7] 0.9315
Feeding position Horizontal -4.1 [-15.9; 7.7] 0.4904 0.6892
Mixed -4.9 [-16.3; 6.6] 0.3997
History of allergic conditions and diseases 2.7 [-2.2; 7.6] 0.2723
Family history of hearing impairment 4.2 [-0.9; 9.3] 0.1079
Vaccination on schedule -1.3 [-7.6; 5.0] 0.6892
Episodes of impaired breath -3.8 [-8.4; 0.9] 0.1111
History of acute otitis media 6.7 [1.5;11.9] 0.0128
Otorrhea 4.7 [0.6; 8.8] 0.0448
Use of ethanol containing ear drops 5.6 [0.3; 10.9] 0.0353
Sleep obstructive apnea syndrome 0.0 [-4.7; 4.8] 0.9889
p* - p-values were evaluated in comparison with the base figures; p** - p-values were evaluated in comparison of subgroups
Discussion
One of the most common causes of conductive hearing loss is chronic inflammatory diseases of the ear, such as otitis media with persistent discharge due to perforation of the tympanic membrane. Without adequate treatment of chronic otitis media, some of the symptoms of the disease -hearing loss or ear discharge - can significantly reduce the patient's quality of life [13, 21].
There is a wide range of modified and non-modified risk factors of chronic otitis media. The assumption about the role of heredity in the chronicity of the inflammatory process in the middle ear is confirmed by a large-scale longitudinal study by Rovers et al. (2002). A prospective follow-up of 1373 pairs of twins in England and Wales demonstrated the concordance of the middle ear disease scale (MEDS) with different variables. If in the development of acute otitis media the influence of the external environment was decisive (0.18 vs 0.10), then heredity turned out to be a statistically significant anamnestic factor for COM (0.57 vs 0.72) [16]. Another risk group for the development of inflammatory pathology of the middle ear are children with congenital pathology of the facial skeleton. These data are also confirmed by a series of experimental studies, during which a gene responsible for the development of one or another bone and cartilage structure of the facial skeleton was deactivated in knock-out mice. Such interventions led to various anatomical and physiological disorders of the Eustachian tube, followed by the development of inflammation of the middle ear [6, 7, 17]. In addition,
adenoiditis can serve as an independent variable that has a prognostic value in the success of surgical treatment of patients with COM. According to Hong et al. (2008) one third of cases of chronic inflammatory pathology of the middle ear is accompanied by adenoiditis, and adenotonsillectomy reduces the frequency of exacerbations of chronic reflux and significantly improves the function of the Eustachian tube [8]. Another important risk factor for the development of pathology of the middle ear is the passive smoking. Children of smoking women are especially at risk, in this case, the likelihood of developing otitis media increases by 50% or more [19]. Another modifiable cause contributing to infection of the middle ear cavity is the use of pacifiers and teethers. The results of a controlled cohort study by Niemela et al. (2000) showed that children whose parents stopped using pacifiers after reading an information booklet about their dangers had 33% fewer episodes of acute otitis media [12].
The results of our investigation demonstrated that some prevalent characteristics of paediatric patients with chronic otitis media may act as possible risk factors for the impairment of hearing function. This data is concordant with the data from other studies. There is significant decrease of hearing function (more than 40dB) in every fifth child with chronic otitis media [1]. Thirty percent of patients with bilateral sensoneural loss of hearing had the middle ear disorder. Furthermore each exacerbation of the inflammatory process may worsen the already existing hearing impairment [10]. In its turn the impairment or loss of
hearing is followed with development and speech delay, the worsening of verbal communication and socialization, and behaviorial and cognitive disorders [20].
Conclusion
Thus, the avoiding of acute inflammatory middle ear diseases and total cancelling of treatment with ethanol containing ear drops may contribute greatly in the prevention of hearing loss and impairment.
Authors contribution:
Shamshudinov T. initiated the study, collected personal and clinical data.
Shamshudinov T. and Taukeleva S. designed the study and wrote the manuscript together.
Shamshudinov T. contributed to statistical analysis.
All authors read and approved the final manuscript.
Competing interests: The authors declare that they have no competing interests.
Funding: This research was carried out as the part of PhD project.
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Corresponding Author
Shamshudinov Timur - Head of Department, City Center of Pediatric Otorhinolaryngology, General Hospital №5, Almaty, Republic of Kazakhstan.
Mailing address: Republic of Kazakhstan, 005056, Almaty, 46, Al-Farabi Street. E-mail: [email protected] Mobile phone: +77012041070
