|Year : 2019 | Volume
| Issue : 1 | Page : 36-44
Effect of weight reduction and exercise program on patients with obstructive sleep apnea
Howaida K Zatton1, Eman A Metwaly1, Ashraf E Elshora2
1 Department of Medical Surgical Nursing, Faculty of Medicine, Zagazig University, Zagazig, Egypt
2 Department of Chest Diseases, Faculty of Medicine, Zagazig University, Zagazig, Egypt
|Date of Submission||25-Nov-2018|
|Date of Acceptance||04-Feb-2019|
|Date of Web Publication||10-May-2019|
Eman A Metwaly
Department of Medical Surgical Nursing, Faculty of Nursing, Zagazig University, 44519
Source of Support: None, Conflict of Interest: None
Background Obesity is the most important risk factor for obstructive sleep apnea (OSA).
Aim The aim of the study was to evaluate the effectiveness of weight reduction and exercise program on patients with OSA at a university hospitals in Egypt.
Subjects and methods Research design: A quasi experimental one group pre/post test design was utilized to achieve the aim of the study.
Subjects A purposive sample included 30 patients with a confirmed diagnosis of OSA were recruited in this study. The program implemented through 10 months.
Tools of data collection Five tools of data collection were used: (1) A structured interview questionnaire. (2) Berlin questionnaire. (3) Epworth sleepiness scale. (4) Questionnaire of sleep apnea, and (5) Questionnaire to assess sleep disturbance symptoms associated with obesity
Results There was a significant reduction in weight through decreasing in BMI, neck circumference, and waist circumference with mean±SD 103.87±21.11, 35.27±7.66, 36.67±4.85, 112.83±16.51 respectively after intervention of program that reflected then on decreasing sleep disturbance symptoms associated with obesity. The sleep efficiency increased after intervention of program with mean±SD 88.32±8.50 through increasing in Base SPO2% (oxygen saturation during daytime) and mini SPO2% and reduction in sum of desaturation (difference between sleep and awake), snoring index, AHI (apnea-hypopnea index). In addition, there was a reduction in daytime and nocturnal symptoms of sleep disorder breathing after intervention of program.
Conclusion Hence, it can be concluded that the application of a balanced and low calorie dietary intake and regular exercise training for upper airway was effective on improving severity of OSA.
Keywords: exercise program, obstructive sleep apnea, weight reduction
|How to cite this article:|
Zatton HK, Metwaly EA, Elshora AE. Effect of weight reduction and exercise program on patients with obstructive sleep apnea. Egypt Nurs J 2019;16:36-44
|How to cite this URL:|
Zatton HK, Metwaly EA, Elshora AE. Effect of weight reduction and exercise program on patients with obstructive sleep apnea. Egypt Nurs J [serial online] 2019 [cited 2019 Aug 25];16:36-44. Available from: http://www.enj.eg.net/text.asp?2019/16/1/36/257967
| Introduction|| |
Obstructive sleep apnea (OSA) is a chronic disorder, characterized by repetitive stops and starts in breathing throughout a night of sleep. As muscles within the throat relax, partial (hypopnea) or complete (apnea) blockage of the airway occurs, resulting in symptoms such as snoring, gasping, or choking. Other nighttime events associated with intermittent breathing interruptions include diminished oxygen saturation and arousals from sleep (The Institute for Clinical and Economic Review, 2012).This disorder can lead to excessive daytime somnolence and fatigue, which, in turn, may cause vehicular and industrial accidents. In addition to neurocognitive sequelae, OSA is associated with increased cardiovascular disease morbidity and mortality (Dobrosielski et al., 2015).
A variety of risk factors found to be associated with OSA in several studies have been studied to determine its strength of association with OSA. Obesity has been identified as a strong risk factor, and a number of other parameters such as BMI, waist circumference (WC), waist/hip ratio, neck circumference (NC), neck length, percentage predicted NC, percentage of body fat, and skinfold thickness. Sex, age, smoking, and alcohol intake have also been found to be independent correlates of the apnea–hypopnea index (AHI) (Sharma et al., 2006).
Obesity is the strongest predictor of OSA and weight loss has been recognized as an option for effective management of OSA. The American Academy of Sleep Medicine recommends weight loss through lifestyle modification (e.g. dietary change and exercise) as behavioral treatment options for improving the AHI in obese patients with OSA (Patrascu and Manea, 2018).
Obesity incidence is increasing globally; the prevalence of obesity in Asian countries has risen to about 30. There is a linear correlation between obesity and OSA. In obese people, fat deposits within the upper respiratory tract narrow the airway; there is a decrease in muscle activity in this region, resulting in hypoxic and apneic episodes, ultimately leading to sleep apnea. These episodes of hypoxia/apnea cause a decrease in oxygen that is available in body tissues and blood vessels. The diminished action causes tissue hypoxia, which is the main contributing factor to atherosclerosis, the main risk factor for cardiovascular diseases (Shazia et al., 2017).
Lifestyle change is an integral part of the management of sleep apnea. Smoking cessation, weight loss, reduced alcohol intake (especially at night), and decreased use of sedatives will all help with both the condition itself and with general health and well-being. However, such changes are not always easy to make, especially if the person is under stress, while trying to achieve too many goals at the same time can be counterproductive, for example, it is common for people to put on weight when trying to stop smoking and this may exacerbate the condition (Malcolm, 2005).
Nursing interventions begin with identifying patients at risk for OSA even if the patient has not expressed concerns about the signs and symptoms of OSA, like snoring and excessive daytime somnolence. So, nurses should pay particular attention to patients with neurobehavioral problems such as anxiety, depression, and anger; cardiovascular problems such as hypertension, heart failure, angina and/or myocardial infarction; and type 2 diabetes and/or obesity (Simmons and Pruitt, 2012). Therefore, the purpose of this study was to evaluate the effect of weight reduction and exercise program on improving OSA.
The overall prevalence of any OSA ranged from 9 to 38% in the general adult population, from 13 to 33% in men and from 6 to 19% in women, although much higher in the elderly groups. There is no epidemiological study about OSA in Egypt.
In addition to its high magnitude, the clinical importance of OSA comes from its cardiovascular effects, consequences on morbidity and mortality and also neuropsychological changes that increase the occurrence of occupational and traffic accidents. OSA is a risk factor for hypertension and it is also known that high blood pressure risk increases with the severity of OSA. In fact, given the high frequency of OSA within individuals with hypertension, the latest standard for hypertension diagnostic approach recommends performing OSA diagnosis in cases of high blood pressure which are resistant to treatment and have a non-Dipper pattern on 24 h records of blood pressure.
Significance of the study
OSA is a significant problem in the USA and worldwide. The prevalence in men is estimated to be between 3 and 7% and the prevalence in women to be between 2 and 5%. Obesity is considered the main risk factor for OSA, and being overweight is also a risk factor. Some patients with OSA are not obese or overweight. OSA occurs in approximately 48% of people who have a BMI of greater than 28 and is more common with advancing age. Less common in children, OSA affects about 3% of them. As OSA is often unrecognized, it may be untreated and lead to medical and employment problems. These problems can be costly; lead to unintended injuries, depression, and anxiety; and affect social and family relationships.
| Aim|| |
The aim of the study was to evaluate the effect of weight reduction and exercise program on patients with OSA at a University Hospital.
- Assess nocturnal and daytime symptoms of sleep breathing disorders.
- Design and implement the weight reduction and exercise program.
- Evaluate the effect of weight reduction and exercise program on patients with OSA.
- Mean scores of polysomnographic data of the patient will improve after intervention than before.
- Daytime symptoms of sleep breathing disorder will be low after intervention than before.
- Nocturnal symptoms of sleep breathing disorder will be low after intervention than before.
- Mean scores of Epworth test, Berlin, and apnea questionnaire will decrease after intervention than before intervention.
- Mean scores of sleep disturbance symptoms associated with obesity will be low after intervention than before.
| Participants and methods|| |
A pretest and post-test quasi-experimental design was used to achieve the aim of the study.
The study was conducted in Sleeping Disorders Unit of Chest Department, University Hospitals in Egypt.
Purposive sample of 30 adult patients with OSA were recruited in this study. The sample was calculated by power and the sample size calculated through Epi Info (Epidemiological Information System, http://www.cdc.gov/epiinfo/) software version 6 according to the following collected data, the confidence level 95% and a power of study 80%.
The following inclusion criteria were established: newly diagnosed sleep apnea patients, able to exercise, and their age ranged between 18 and 60 years and approval to participate in the study, while, the exclusion criteria included patients with physical obstruction in the nose or throat, abnormal large tonsils (who need surgery to improve OSA), and the presence of psychiatric history.
- A structured interview questionnaire for patients: it was designed by the researchers in the light of relevant literatures. It included the following parts:
- Demographic characteristics of the patient, for example, age, sex, marital status, occupation, level of education, etc.
- Physical examination of the patient (pretest/post-test), for example, height, weight, BMI, and NC and WC.
- Comorbidity, for example, respiratory system, gastrointestinal tract, neurological, etc.
- Polysomnographic data of the patient (pretest/post-test) is used to diagnose sleep apnea, including sleep efficiency, snoring index, AHI, etc.
- Nocturnal symptoms of sleep disorders breathing (pretest/post-test).
- Daytime symptoms of sleep breathing disorder (pretest/post-test).
- Berlin questionnaire (Netzeret al., 1999) (pretest/post-test): is a simple, self-administered validated predictive assessment tool designed to assess three OSA risk categories: the presence and frequency of snoring behavior, wake time sleepiness or fatigue, and a history of obesity and/or hypertension. Scoring, Category 1 is positive with greater than or equal to 2 positive responses to questions 1–5. category 2 is positive with greater than or equal to 2 positive responses to questions 6–9. category 3 is positive with a self-report of high blood pressure and/or a BMI of greater than 30 kg/m2, high risk of OSA. Two or more categories were scored as positive. Low risk of OSA less than two categories were scored as positive.
- Epworth sleepiness scale (ESS) (Johns, 1991) (pretest/post-test): to measure a patient’s usual level of daytime sleepiness or average sleep propensity: score 0: would never doze, 1: slight chance of dozing, 2: moderate chance of dozing, and 3: high chance of dozing. Total score greater than or equal to 12 is considered excessive daytime sleepiness.
- Questionnaire of sleep apnea (pretest/post-test): scores 1: rarely, 2: sometimes, 3: often, 4: most of the time.
- Questions to assess sleep disturbance symptoms associated with obesity (pretest/post-test): scoring, yes: 2, sometimes: 1, no: 0.
Content validity and reliability
Once the tools were prepared, their face and content validity were ascertained by a panel of three experts (two professors of medical surgical nursing and one professor of chest diseases), who revised the tools for clarity, relevance, applicability, comprehensiveness, and ease of implementation. The agreement percentage was between 80 and 100%. In light of their assessments, minor modifications were applied. The reliability of the Berlin scale was assessed in the present study, showing reliability with a Cronbach’s α coefficient (r=0.97), and ESS showing reliability with a Cronbach’s α coefficient (r=0.97).
Description of the intervention
The intervention program was designed to be practical in nature addressing the knowledge and practice for the patient with OSA. The program was developed after reviewing the related literature (Strobel and Rosen 1996). It covered two sections (OSA and obesity). The first section (OSA) included sleep cycle, OSA definition, causes, signs, and symptoms; diagnosis, treatment, exercise for improving sleep apnea included; exercise of mandible, tongue, soft palate, neck, and throat; and promotion of self-management and patient education. The second section (obesity) included measuring BMI, following balanced diet using the food pyramid paradigm as well as ways to reduce caloric intake. No special diets, medications, or behavioral modifications were prescribed. A booklet containing the program materials and illustrations was prepared in simple Arabic language.
Implementation of the program consisted of theoretical and practical parts. The theoretical part implemented through seven sessions. Each session took 30 min The practical part is implemented through 10 sessions. Each session get even 45 min. One month for the preparatory phase, 1 month for the theoretical part, and 3 months for the practical part, then collecting the posttest, using the same data collection tools after four months of intervention which took one month. The program was implemented through presentation, group discussion, videos, and role play.
After an official permission was granted from the research and ethics committee at the Faculty of Nursing, Zagazig University, and from the Director of Zagazig University Hospitals. Additional written consents were taken from the patients who participated in the study after explaining its purpose. The aim of the study and the procedures were explained to patients to obtain their cooperation for data collection. The study was implemented during the period from September 2017 to June 2018, which lasted over 10 months. The data used was collected every day from the sleep disorders unit of Chest Department, Zagazig University Hospital from 9:00 a.m. to 1:00 p.m. The patients were grouped for administering the content of the program. Each group included 4–5 patients.
The patients were handed the program booklet, with some explanations from the researchers regarding its use. At the end of the program, the effectiveness of the program was evaluated through a post-test, using the same data collection tools after 4 months of intervention.
A pilot study for tools of data collection was carried out on three patients within the selected criteria to test for clarity, relevance, comprehensiveness, understandability, feasibility, applicability, and ease of implementation. The results of the data obtained from the pilot study helped in the modification of the tools. The items were then corrected or added as needed. The patients who shared in the pilot study were excluded from the main study sample.
The ethical research considerations in this study included the following: the research approval was obtained before the program implementation, the objectives, and the aims of the study were explained to the participants, the researcher confirmed the confidentiality of participants, voluntary participation, and right to withdraw from study at any time without penalty.
The collected data were coded, computed, and statistically analyzed using SPSS (the Statistical Package for the Social Sciences; SPSS Inc., Chicago, Illinois, USA), version 22. Qualitative variables were presented as frequency and percentages using χ2 for comparison of categorical variables and was replaced by Fisher’s exact test if the expected value of any cell was less than 5. Quantitative continuous variables were presented as mean±SD if they were normally distributed and paired t-test was used for comparison. Quantitative continuous variables were presented as minimum to maximum and media if they were not normally distributed using Wilcoxon signed-rank test for comparison. The difference was considered significant at P less than or equal to 0.05.
| Results|| |
[Table 1] shows that 66.7% of patients had their age between 50 and 60 years with mean±SD of 53.2±9.77. Also the table shows that 96.7% were married, had insufficient outcome, and had insufficient sleep hours as they sleep 5 to less than 7 h and 100% were living with their family.
[Table 2] shows that the mean±SD of weight was 113.33±22.98 before intervention and decreased to 103.87±21.11 after intervention. Also, the mean±SD of BMI was 42.82±7.66 before intervention and decreased to 35.27±7.66 after intervention. In addition, the mean±SD of NC was 43.70±4.62 before intervention and then decreased to 36.67±4.85 after intervention.. Also, the mean±SD of WC was 124.13±16.93 before intervention and decreased to 112.83±16.51 after intervention. The table showed a statistically significant difference in weight, BMI, NC, and WC after intervention (P=0.000).
|Table 2 Physical examination of the studied group before and after intervention intervention (n=30)|
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[Table 3] cleared that the most common comorbidities were hypertension, psychological state, and activities of daily livings; 36.7% of patients had hypertension before intervention and decreased to 20% after intervention. Also, 66.7% had no psychological problem, after intervention. None of the patients was independent in activities of daily living before intervention while 93.3% of them became independent in their activities of daily livings after intervention.
|Table 3 Comorbidities of the studied group before and after intervention (n=30)|
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[Table 4] illustrates that the mean±SD of sleep efficiency was 81.13±13.77 before intervention and increased to 88.32±8.50 after intervention; Also, base and mini SPO2% (oxygen saturation) was 94.07±3.08 and 75.63±11.12, respectively, before intervention and increased to 95.23±2.16 and 82.27±6.71, respectively, after intervention. Furthermore, mean±SD of the sum of desaturation was 33.73±13.83 before intervention and decreased to 22.35±11.06 after intervention. Also, the mean±SD of snoring index was 224.87±159.74 before intervention and decreased to 102.77±73.37 after intervention. In addition, the mean±SD of AHI was 49.68±22.47 before intervention and decreased to 29.43±12.47 after intervention. The table shows a statistically significant difference in sleep efficiency, SpO2, sum of desaturations, snoring index, and AHI (P=0.000).
|Table 4 Polysomnographic data of the studied group before and after intervention (n=30)|
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[Table 5] indicates that 50% of the studied patients had a decrease in snoring and 50% of them had no observed apnea. Also, 93.3% of them had no chocking and nocturnal polyuria, 86.7% had no insomnia after intervention with statistically significant difference (P=0.000).
|Table 5 Nocturnal symptoms of sleep-disordered breathing before and after intervention (n=30)|
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[Table 6] show that the studied patients had difficulty in waking up, dry mouth on waking, morning headache, excessive daytime sleepiness, tiredness, and irritability before intervention (76.7, 70.0, 76.7, 96.7, 76.7, and 70.0%, respectively) and the same symptoms disappeared after intervention (70.0, 63.3, 73.3, 66.7, 83.3, and 83.3%, respectively) with statistically significant difference (P=0.000).
|Table 6 Daytime symptoms of sleep-disordered breathing before and after intervention (n=30)|
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[Table 7] presents that 100% of patients were at high risk before intervention, while 80% of them had no risk after intervention with statistically significant difference (P=0.000).
[Table 8] clarifies that the mean±SD of Berlin, Epworth, and sleep apnea were 8.63±2.06, 15.30±4.64, 53.77±8.67, respectively, before intervention and then decreased to 3.07±1.71, 7.57±2.62, 31.20±1.40, respectively, after intervention with statistically significant difference (P=0.000).
|Table 8 Average score of Berlin questionnaire, Epworth sleep, test and questionnaire of sleep apnea before and after intervention (n=30)|
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[Table 9] identifies that patients had difficulty in breathing, fatigue and stress, headache, sleep disturbance, weakness in physical strength, nervousness and anger, and snoring during sleep before intervention (96.7, 93.3, 76.7, 96.7, 100, 100, 96.7%, respectively), then the patients sometimes had the same symptoms after intervention (96.7, 93.3, 83.3, 86.7, 96.7, 76.7, 83.3%, respectively). Also, the table showed a statistically significant difference in all sleep disturbance symptoms associated with obesity (P=0.000).
|Table 9 Sleep disturbance symptoms associated with obesity before and after intervention (n=30)|
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| Discussion|| |
The importance of weight loss and its effectiveness in treating OSA are evaluated in earlier studies. The bulk of studies concerning weight reduction and sleep disorder have evaluated the result of a low-calorie diet program in moderately overweight patients with OSA (Tuomilehto et al., 2009). However, most of the dietary modes urged for weight loss specialize in energy content and macronutrient composition. Persons who are overweight or who have category I obesity should reduce their energy intake by 500 kcal/day. Persons with category II and category III obesity ought to attempt for 500–1000 kcal/day reduction. With a reduction of 500 kcal/day energy intake, a weight reduction of 0.5 kg/week can be achieved (Fock and Khoo, 2013).
As regards demographic characteristics, two-thirds of patients included in the study had their age more than 50 years. This was in the same line with Sharma et al. (2006) who mentioned that age was also determined to be an independent predictor of OSA. Older patients (i.e. >45 years of age) had more than three times the increased risk of having OSA. Regarding physical examination, after intervention there was a significant reduction in weight, BMI, NC, and WC. This may be due to the effectiveness of the program. This agreed with Barnes et al. (2009) who found that there was a significant reduction in BMI, body fat percentage, and abdominal girth.
As regards NC, there was a significant reduction in NC after intervention. This result was in accordance with Mohamed et al. (2016) who found that there was decrease in NC for the intervention group.
Concerning comorbidities, there was reduction in blood pressure after the intervention program. This result was in accordance with Norman et al. (2000) who proclaimed that the participants demonstrated a significant improvement in cardiovascular conditioning as well as a significant reduction in the mean resting blood pressure profile post-training.
According to the polysomographic data, there was a significant reduction in snoring index, AHI from 50 to 30, and desaturation. There was also a significant increase in sleep efficiency and SpO2%. This may be due to the effect of exercises (including mandible, tongue, and soft palate) on improving OSA through decreased upper airway edema and collapsibility that also improve tongue position and overcome the bad action of soft palate and uvula mostly present in OSA. Also exercises have a positive effect on facial muscles contractility during chewing and training muscles to elevate the mandible and the hyoid bone to avoid mouth opening.
This result was supported by Puhan et al. (2005), who explained that there was a reduction in AHI (P=0.05) by playing didgeridoo for 4 months indicated by the decrease in the collapsibility of the upper airways. Also, this result was in accordance with Iftikhar et al. (2014) who found a significant reduction in the AHI and daytime sleepiness. There was increase in sleep efficiency and peak oxygen consumption in adult patients with OSA.
The results of the present study clarified that there was a significant reduction in nocturnal and daytime symptoms of sleep-disordered breathing after implementing the program. This can be due to the effectiveness of the program on the reduction of weight, NC and WC, and AHI that reflected on increasing sleep efficiency, and improvement in nocturnal and daytime symptoms of OSA. This interpretation is in the same line with Norman et al. (2000) who clarified that a number of patients with OSAS have reported that they had fewer symptoms or no symptoms of OSAS when they were previously exercising regularly and weighed significantly less than they did at the time of diagnosis.
The finding revealed that there was a significant reduction in category I, II, and III of Berlin questionnaire after intervention of the program. All the studied patients were at high risk of OSA by Berlin questionnaire before intervention, while 80% of them had no risk after intervention with statistically significant difference. This was in contrast with Karakoc et al. (2014) who reported that the Berlin questionnaire does not seem to be an effective screening tool for clinical and research purposes in determining the risk of OSA.
Finally, there was significant reduction in average score of Epworth test, sleep apnea, and Berlin questionnaire. This was in accordance with Mohamed et al. (2016) who mentioned that daytime sleepiness (ESS) improved significantly to moderate OSA after intervention. This is in accordance with Tuomilehto et al. (2010) who found that the ESS decreased greatly in the intervention group. There was also a significant reduction in ‘witnessed apneas’ in the intervention group.
| Conclusion|| |
On the basis of the results of the present study, it can be concluded that the application of a balanced and low-calorie dietary intake and regular exercise training of upper airway was effective in improving the severity of OSA.
- Replication of the study on a large probability sample to achieve generalization.
- Further studies to evaluate long-term follow-up of the program to improve sleep apnea.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8], [Table 9]