Nigerian Journal of Clinical Practice

: 2019  |  Volume : 22  |  Issue : 12  |  Page : 1722--1727

Evaluation of knowledge level related to obstructive sleep apnea syndrome

H Senturk1, MA Eryilmaz1, H Vatansev2, S Pekgor1,  
1 Family Medicine Clinic, Konya Training and Research Hospital, Konya, Turkey
2 Chest Diseases Clinic, Necmettin Erbakan University, Meram Medical Faculty, Konya, Turkey

Correspondence Address:
Dr. H Senturk
Family Medicine Clinic, Konya Training and Research Hospital, Konya


Objective: Our aim in this study is to evaluate the knowledge level of outpatients about obstructive sleep apnea syndrome (OSAS). Subjects and Methods: This cross-sectional analytical study included 1651 patients and patient relatives who applied to Konya Training and Research Hospital outpatient clinics. Sociodemographic data form and OSAS knowledge level questionnaire were applied to participants. SPSS 21 package program was used for the statistical analysis of the data. It was accepted that p value was <0.05. Results: The average knowledge score in the knowledge level questionnaire was 15.1 (3-33). 61% of the participants had never heard of OSAS before. Those who are married, those living in the city center and women have a higher level of knowledge. When age, education level and income level increased, the score of information also increased. Most of the participants' information source was the social media with 56.5% (n = 364) and least were health workers with 19.8% (n = 127). The knowledge level of people whose information sources were doctors, were significantly higher than other information sources such as nurses, friends, internet and television as. There was no significant difference between the other groups. Conclusion: In our study, it was concluded that the level of knowledge about OSAS in the society was not sufficient and that the society had to be informed about this disease which has serious complications and awareness should be established.

How to cite this article:
Senturk H, Eryilmaz M A, Vatansev H, Pekgor S. Evaluation of knowledge level related to obstructive sleep apnea syndrome.Niger J Clin Pract 2019;22:1722-1727

How to cite this URL:
Senturk H, Eryilmaz M A, Vatansev H, Pekgor S. Evaluation of knowledge level related to obstructive sleep apnea syndrome. Niger J Clin Pract [serial online] 2019 [cited 2020 Aug 8 ];22:1722-1727
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Full Text


Respiratory disorders in the sleep are clinical tables that develop due to pathological changes in the respiratory pattern during sleep and lead to increased morbidity and mortality in these patients. The most common and most serious form of these diseases is the obstructive sleep apnea syndrome (OSAS). OSAS is a syndrome characterized by recurrent episodes of complete or partial obstruction of upper respiratory tract during sleep and decrease in blood oxygen saturation.[1] OSAS leads to serious disease burden and is considered as an independent risk factor for cardiovascular, metabolic and psychiatric disorders, such as hypertension, stroke, diabetes, and depression which are global health problems.[2]

OSAS can be seen in both sexes, all of races, ages, socioeconomic levels, and ethnic groups. Many studies have shown that OSAS is a widespread disease both in the general population and in subgroups of specific diseases and populations, and the frequency is increasing steadily.[3] In studies conducted in different societies, the prevalence of OSAS was reported as 1--7.5% in males and 1.2--4.5% in females.[3],[4],[5],[6] In some groups with higher ages, 90% of men and 78% of women have been shown to have OSAS.[3] In middle age it is more common in men, but in women after menopause it is as common as men. It is thought that as the age increases, the frequency of incidence increases depending on other factors.[5],[7] In a meta-analysis of 24 studies, the prevalence of OSAS was reported from 9% to 38%, showing that prevalence increased with age, and it was more frequent in men and obese people. In a study conducted in Turkey prevalence of OSA found to be 0.9--1.9%.[8]

A study measuring the level of knowledge and awareness of the society about OSAS has not been done before. In this study, we aimed to measure the knowledge level of patients and their relatives about OSAS who applied to the outpatient clinics of Konya Education and Research Hospital and to raise awareness in doing so.

 Subjects and Methods

Study population and study parameters

The study was carried out with patients and their relatives who applied to Konya Education and Research Hospital Polyclinics between February and June 2015. Participants were informed about the study by giving written and verbal information and informed consent was obtained. A total of 1651 people over the age of 18 were included in the study. Those who were previously diagnosed with OSAS, health workers, analphabetic people, and those who did not want to fill the questionnaire were not included in the study. Sociodemographic data form and OSAS knowledge level questionnaire were applied. The questionnaire was written by the authors using the literature. There were 37 questions: 15 questions to measure the level of general knowledge, 10 questions to measure information about symptoms, and 12 questions about predisposing causes. In the general knowledge level questionnaire the answers consisted of 'right', 'wrong', and 'no idea' statements. The 'No idea' option was also considered as wrong answer. In the information of symptoms and predisposing causes questionnaire, it was requested to mark the symptoms and predisposing causes among the given expressions. According to the answers given, 1 information point was given for each correct answer and it was evaluated by calculating the average information scores in each questionnaire part and total questionnaire. Those with a total knowledge score of 12 or less as low level, those with score between 12 and 24 as medium level, and those with a level of 24 or higher considered as high level of knowledge. When relations between sociodemographic information and knowledge scores are evaluated, in some data the average information score were used, and information score groups in some data (low, medium, and high) were used.

Statistical analysis

Data entry and statistical calculations were evaluated using the SPSS 21 package program. Categorical variables were presented as frequency and percentage; numerical variables were presented as mean, standard error (SE), minimum (min), and maximum (max). In single samples in statistical calculations; descriptive statistics, and Kolmogorov--Smirnov and Shapiro--Wilk analyzes of persistent data distribution compatibility tests were used. In binary samples, Mann--Whitney-U test which is a nonparametric tests was used for the difference between the averages and Spearman correlation analysis was used to measure correlation levels. In more than two samples, Kruskal--Wallis variance analysis, which is a nonparametric test, was used for in the comparison of the averages. The results of all analyzes were evaluated at the 0.05 significance level. To determine the number of people which reflect Konya city center; sample size was calculated according to specific age and gender quotas and data from the Turkey Statistical Institute (TUIK). According to this, the study was calculated with a power analysis of 5% error margin and 95% confidence interval in 1100 people. We included 1651 people to study.


The sociodemographic characteristics of the participants are shown in [Table 1].{Table 1}

A total of 22% of the participants had previously known chronic disease. Previously, the rate of referral to the chest diseases policlinic for any reason was 31.3%. And 61% of participants had never heard of sleep apnea syndrome before. 39% had heard of the disease, but only 11.9% stated that their knowledge was sufficient. When the sources of information about sleep apnea were examined, 20.1% were from doctors, 2% were from nurses, 25.3% from friends, 18.9% from internet, and 42% from television (There were also those who had received information from more than one source.). The knowledge level of those who got their knowledge from the doctors was significantly higher than the other groups (p< 0.001). There were no significant differences between the other groups [Table 2].{Table 2}

A total of 37.3% of participants had low knowledge level, 54.3% had medium knowledge level and 8.4% had high knowledge level. The mean knowledge score of the women was significantly higher than males (p = 0.005). The level of knowledge of those aged 30 or over was significantly higher than those aged 29 years or less (p = 0.010). Knowledge level of those whose education level is high school or further was higher than those whose education level is middle school or lower (p< 0.001). A total of 15.5% of civil servants, 5% of workers, 7.6% of unemployed and housewives, 10.6% of retirees, 5.2% of students, 12.3% of tradesmen, and freelancers had a high level of knowledge. The difference between the groups was statistically significant (p< 0.001). 10.2% of the married, 6.3% of the single, and 8.3% of the widow or divorced have high knowledge level. Married peoples level was significantly higher than singles and widowed or divorced persons (p = 0.003). 8.8% of those living in the city center and 4.1% of those living in countryside were in a high level of knowledge. There was a significant difference between them (p< 0.001). OSAS knowledge level was higher in those with higher income levels (p< 0.001). When the correlation between sociodemographic characteristics and information points was examined, it was found that the average knowledge score increased as age, education level, and income level increased (r = 0.055, P = 0.025, r = 0.127, P < 0.001; r = 0.167, P < 0.001). The mean knowledge scores of patients with any chronic illness were significantly higher than those of healthy individuals (p = 0.005) [Table 3].{Table 3}

Although 13.2% of participants thought that snoring was a normal situation, 16.8% stated that they did not have any idea. 81.8% stated that they should apply to the doctor in case of snoring. About sleep respiratory pauses, 84% of the participants indicated that this was not normal and 8.1% had no idea. When the frequency by gender of sleep apnea is asked, 13.6% of the participants thought that it was seen more in men and 6.4% thought that it was seen more in women. 80.1% had no idea. While 61.9% of participants did not know about polysomnography (PSG) necessity in the sleep laboratory for OSAS diagnosis, 36.3% stated that PSG was used for OSAS diagnosis. While 38.6% of the participants thought that OSAS is a curable disease, 57.5% had no idea about this. Only 5.1% stated that the effective treatment of OSAS is continuous positive airway pressure (CPAP). According to the responses to the situations that OSAS can cause if not treated properly; 14% of the participants knew that it could lead to hypertension, 20.1% to heart failure, 39.7% to sudden death in sleep, 29.8% to rhythm disturbance, and 7.3% to diabetes. The rate of those who stated that it can increase the risk of accident when driving was 27.9% [Table 4].{Table 4}

In the symptom information questionnaire, when symptoms that may cause from the sleep apnea are asked; 44% of the participants stated daytime sleepiness, 59.4% tired waking at morning, 71.4% snoring, and 66.9% respiratory arrest during sleep, among the symptoms. The most marked symptom was “shivering in hands” (83.5%), which is a distracter. The most well-known symptom among the symptoms was snoring (71.4%). The least known symptom (10.4%) was the decrease in sexual desire.

In the predisposing factor information questionnaire; participants stated the reasons for sleep apnea as smoking (53.1%), alcohol (36.1%), curved nasal bone (56.4%), hypertrophic tonsils (37.6%), thick neck (10.1%), adenoid hypertrophy (57.4%), large tongue (22.4%), goiter (27.3%), small jaw (4.1%), and obesity (55.2%). The most marked one was “being short” (94.6%) which is a distracter. Adenoid hypertrophy (57.36%) had the highest rate and small jaw (4.06%) had the least rate between correct answers.


In the literature, studies were carried out between medical faculty and dental faculty students and doctors in various fields on knowledge level of sleep disorders and OSAS. But there are very few studies on the knowledge level of the people. In Turkey, there are few studies among physicians[9],[10] but there is no study that measured the public's knowledge about it.

Our study population has similar demographic characteristics to the population according to TUIK2015 data. According to the sociodemographic characteristics, the information points were higher in those who were 30 years or older than those who were under 30 years old. Contrary, there were no differences between age and knowledge scores in several studies conducted with dental school students and doctors.[11],[12]

Contrary to similar studies, women's knowledge scores were higher in our study than males.[13],[14] The information scores of the married people were higher than singles. It is known that OSAS and its major symptom snoring was more likely to seen in men. It can be considered that married women are in need of research and learning related to this subject as closest witness to this situation because of their husbands' snoring. In some studies evaluating the level of knowledge about different diseases, found that women are more knowledgeable and this suggests that women's consciousness of health and desire to research and learn is higher than men.[15],[16],[17]

In our study, those with higher education level, those living in the city center, and those with a high level of income had higher level of knowledge. This is an expected result in terms of the effect of sociocultural level and the ease of access to information sources. Those who have previously referred to the chest diseases policlinic for any reason and those with a chronic illness had more accurate information about OSAS. Patients with chronic illness may have verged because they are more intertwined with health problems and perhaps because of their common symptoms with OSAS.

When the sources of information were examined, it was seen that most of the information was obtained from the social media and least of it from the health personnel. While the knowledge level of those obtain information from doctor is higher, no significant difference was found between the other groups. This proved the importance of the health personnel to inform the society correctly.

In our study, 70% of participants stated that snoring was not a normal condition and 81.8% said that snoring individuals should apply to the doctor. These questions have not been addressed in other studies. In our study, 49.9% of the participants stated that sleep apnea was a condition where stopped, ensnarled or decreased breathing during the sleep. Shaw et al.'s study which is the only study done on this subject in the literature revealed that when participants were asked about their thoughts about OSAS, it has been perceived in many different ways. The three most frequently encountered responses are: a kind of insomnia, a condition that develops with age, and a condition that depends on activities during the sleep. Some expressed OSAS as be unable to sleep and some as frequent waking at night. Some stated that as a natural consequence of aging. Although OSAS is misunderstood like this, answers to the results or effects of OSAS have become more accurate. Symptoms indicated by participants include headache, daytime fatigue, lack of concentration, anxiety, and hypertension.[18] Similarly, also in our study, it was seen that the symptoms were more known when the knowledge level about OSAS was low. A total of 13.5% of the participants in our study stated that OSAS was seen more in men. In similar studies conducted on students, 72% and 61.5% of the respondents respectively stated that OSAS is more frequent in males.[11],[19] We can say that the effect of gender is obviously less known among the population. The common expressions in our work and other studies answered right at lower rate in our study, such as PSG is the diagnostic method, CPAP is the treatment method, OSAS causes hypertension and rhythm disturbance, increases the risk of accident, causes snoring and daytime sleepiness, and alcohol is a risk factor. This situation may have been caused by that other studies have been conducted between doctors and medical faculty and dental faculty students.[11],[19],[20],[21] In our study, only 15.6% of the participants were in the high knowledge level, 67.9% of them in moderate level, and 16.4% of them in low knowledge level. The presence of sleep laboratory in two large hospitals and some private hospitals in our city may have contributed to the public's perception on this issue and may have affected the results. The strengths of our study are it is the study on the knowledge level of OSAS among society and the sample size is sufficient to represent the population of Konya. In addition, the study was done in one of the largest hospitals in Central Anatolia. The findings also reflect Central Anatolia because patients come from near cities to our hospital. Limitations of our study are there was not validity and reliability of the questionnaire we used, and study was conducted only on patients and relatives who applied to the hospital.


The ratio of people who has never heard about OSAS before in our community is found to be quite high (61%). The level of knowledge of women, married people, civil servants, those with a high education and income level, those living in the city center, those with chronic diseases, and those who had previously been examined in the chest diseases policlinics was found to be higher. Despite being most commonly referred to as television and social media as a source of information, most accurate information source were doctors.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of Sichuan University research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The Ethics Committee of Necmettin Erbakan University approved this study.

Informed consent

Informed consent was obtained from all individual participants included in the study.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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