Abstract

Background: This study aims to evaluate the effect of self-care interventions based on sleep hygiene practices, nutrition, and physical activity on sleep quality in post-coronary artery bypass grafting patients.

Methods: This randomized-controlled study included a total of 146 patients (109 males, 37 females; mean age 55.31 years; range, 41 to 65 years) who underwent isolated coronary artery bypass grafting at Seyyed Al- Shohada Hospital of Urmia Medical Sciences University, between September 2017 and May 2018. The patients were divided into two groups as the self-care intervention group (n=73) and as the control group (n=73). The self-care intervention group received six educational courses on sleep hygiene, nutrition, and physical activity. Then they received individualized consulting weekly for three months. The control group was instructed to continue their normal life and routine care and received no education. The Demographic Information Form and the Pittsburgh Sleep Quality Index were used for data collection.

Results: The mean Pittsburgh Sleep Quality Index scores in the self-care intervention group decreased to 7.1±2.3 after the intervention, while it increased to 9.5±2.1 in the control group. There was no significant difference between the two groups in terms of the mean global Pittsburgh Sleep Quality Index scores before the study (p=0.91); however, the scores were statistically significantly higher after the self-care intervention (p=0.001).

Conclusion: Patients undergoing coronary artery bypass grafting may benefit from self-care interventions based on sleep hygiene, nutrition, and physical activity to improve the quality of sleep.

Adequate amount and good quality of sleep are basic human needs.[1] Sleep quality is defined as the subject"s satisfaction with sleep experience, integrating domains of sleep initiation, sleep maintenance, sleep quantity, and refreshment upon awakening.[2] Emerging evidence has assigned an important role to sleep as a modulator of metabolic homeostasis. The impact of variations in sleep duration, sleep-disordered breathing, and chronotype to cardiometabolic function encompasses a wide array of perturbations spanning from obesity, insulin resistance, type 2 diabetes, the metabolic syndrome, cardiovascular disease risk, and mortality in both adults and children.[3] Defects in sleep quality can disturb emotions, thoughts, and motivation. Individuals with poor quality of sleep show many physical and cognitive symptoms, such as tiredness, exhaustion, difficulty concentrating, decreased pain threshold, loss of appetite, nervousness, anxiety, and depression.[4]

Coronary artery bypass grafting (CABG) is common in developed countries. In Iran, 60% of open heart surgeries are CABG.[5] Undergoing CABG is a significant life event with an important psychoemotional impact on patients and their families. Most patients report fear and anxiety, and many of them report that uncertainty about the future is more disturbing than their chest pain.[6] Coronary artery bypass grafting contributes to issue such as survival, quality of life, and increase in expectations.[7] Sleep disturbances are common after cardiac surgery. They are reported to occur in 60 to 80% of patients in the immediate post-operative period, and alterations in sleep pattern seem to continue to occur in 39 to 69% of cardiac surgery patients during the first month after hospital discharge.[8] The sleep pattern of these patients is characterized by shorter periods, frequent awakenings, and a perception of poor quality. As a consequence of fragmented sleep, patients usually experience increased daytime sleepiness, fatigue and irritability, which may reduce their motivation to attend rehabilitation therapy, prolong the recovery period, and increase the length of hospitalizations.[9]

Self-care is considered as individuals" performance or practice of activities for their own benefit to maintain health, life, and well-being.[10] Concerning undesirable effects of sleep disorders, nurses should ascertain that their patients have enough sleep and rest as a care duty.[11]

To the best of our knowledge, there is no study examining the effects of self-care interventions including sleep hygiene, physical activity, and healthy nutrition on quality of sleep in post-CABG patients. Therefore, in the present study, we aimed to evaluate the effectiveness of self-care interventions as a safe and well-tolerated method, irrespective of any equipment or device used, on sleep quality in post-CABG patients. Our hypothesis was that self-care interventions would improve the quality of sleep in the intervention group.

Methods

This single-center, randomized-controlled study (RCT No. IRCT20180515039677N1) with a prepost- test design included a total of 146 patients (109 males, 37 females; mean age 55.31 years; range, 41 to 65 years) between September 2017 and M ay 2 018. I nclusion c riteria w ere a s f ollows: undergoing isolated CABG (not combined with valve replacement surgery), willingness to participate in the study, giving a written informed consent, having sleeping problems on the basis of the Pittsburgh Sleep Quality Index (PSQI), and being older than 18 and younger than 65 years. Exclusion criteria were as follows: previous diagnosis of sleep disorders, chronic use of hypnotics, previous additional surgery within the last six months, participation in another interventional sleep study within the last six months, having major depression, a physical/psychiatric disorder which could seriously impair their physical mobility, and giving consent for withdrawal from the study. The flow diagram is shown in Figure 1. A written informed consent was obtained from each participant. The study protocol was approved by the Ethics Committee of Urmia University of Medical Sciences, Urmia, Iran (IR.UMSU.REC.1396.234). The study was conducted in accordance with the principles of the Declaration of Helsinki.

For randomization in this study, an independent investigator made random allocation cards using computer-generated random numbers. The allocator kept the original random allocation sequences in an inaccessible third place and worked with a copy. Instead of the letters A and B, she used the codes I and C (I for the intervention group and C for the control group) to avoid further confusion. Then, she continued randomization until 40 samples were allocated to the intervention group and 40 to the control group.

Figure 1: CONSORT flow diagram.

Intervention method
Interventions for experimental group
First part of intervention (Self-care education)
A master nursing student at the Division of Critical Care Nursing instructed self-care courses for the intervention group. She also took self-care educational course during her master program before this research.

The self-care educational courses were held for each 10 to 11 patients twice a week. Each session lasted 1.5 h, and in total six sessions (including two sessions on sleep hygiene, two sessions on healthy nutrition emphasized on necessary diet changes to get a good night"s sleep, and two sessions on physical activity were hold for each of these courses.

In total, seven courses, each of them including six educational sessions, were held. The patients participated in these courses according to the schedule. Fortunately, in the present study, the participants did not have more than one absence session, and the content of the missed session was instructed to them individually at the end of next session.

Second part of intervention (weekly consulting)
All participants in the intervention group were asked to attend at the counseling sessions (for solving their self-care problems) weekly for three months.

In these counseling sessions, self-care checklist including dietary plan, physical activity, and sleep hygiene during the last month was reviewed by the investigator and its feedback was given to them. Furthermore, they were encouraged to have healthy lifestyle including sleep hygiene, healthy nutrition emphasized on necessary diet changes to get a good night"s sleep, and physical activity.

Interventions for control group
The control group had their routine/traditional care and treatment. They did not receive any self-care intervention or counseling.

Data collection and measurements
A Demographic Information Form (DIF), and the Persian Version of PSQI were used to collect data. The PSQI is a self-rated questionnaire to evaluate subjective sleep quality in general and clinical populations over the previous month. It consists of 19 self-related questions and five questions that should be answered by bedmates or roommates. These last five questions are used only for clinical information and, therefore, they are not tabulated in the scoring. The 19 self-related questions are categorized into seven components and graded on a score ranging from 0 to 3. The PSQI components are as follows: (i) subjective sleep quality, (ii) sleep latency, (iii) sleep duration, (iv) habitual sleep efficiency, (v) sleep disturbances, (vi) use of sleeping medication, and (vii) daytime dysfunction. The sum of these components yields one global score, which ranges from 0 to 21, where the highest score indicates the worst sleep quality. A global PSQI score greater than 5 indicates major difficulties in, at least, two components or moderate difficulties in more than three components.[12] The validity and reliability of the PSQI were carried out in several studies. In the study of Ghavami and Akyolcu, Cronbach"s alpha reliability coefficient of the Persian version of the PSQI scale (a) in the first measurement was calculated as 0.746 and it was 0.783 in the last measurement.[13] Furthermore, Farrahi Moghaddam et al.[14] reported a sensitivity of 100%, specificity of 93%, and a Cronbach"s alpha coefficient of 0.89% for the Persian version of the questionnaire. The PSQI and DIF were filled for all the participants before the intervention. The PSQI was filled again for all the participants one month after the end of the intervention.

Statistical analysis
Statistical analysis was performed using the SPSS version 15.0 software (SPSS Inc., Chicago, IL, USA). Descriptive data were expressed in mean ± standard deviation (SD) and number (n) and frequency (%). To examine the quantitative variables, paired sample t-test was used, while the chi-square test was used to examine the qualitative variables. The Smirnov- Kolmogorov test was used to analyze the normal distribution of sleep quality scores in both groups before or after the self-care intervention. To compare the global PSQI scores before and after self-care intervention in each of the study groups, the paired t-test and independent t-test were used. The sample size was calculated as 73 participants for each group, based on the findings of a similar study[2] with a confidence interval (CI) of 95% and a test power of 80%. A p value of 0.05 was considered statistically significant.

Results

In the present study, 23.3% participants in the control group and 27.4% participants in the intervention group were female. A total of 60.3% participants in the control group and 39.7% in the intervention group were illiterate. In the control group, the mean age was 55.7±5.1 years, while it was 56.9±6.5 years in the intervention group. In addition, 100% participants in both groups were married.

The distribution of sleep quality scores was normal (p>0.05) (Table 1).

Table 1: Sleep quality scores before and after self-care intervention*

Based on the paired t-test, in the intervention group a significant difference was found between the mean global PSQI scores before and after the intervention (p=0.001). However, in the control group, there was no significant difference between the mean global PSQI scores before and after the intervention (p=0.36) (Table 2).

Table 2: Global Pittsburgh Sleep Quality Index scores before and after self-care intervention*

Based on the results of the independent t-test, there was no significant difference in the mean global PSQI scores before the intervention between the control and intervention group (p=0.914), although the difference between the two groups was significant after the intervention (p=0.001) (Table 3).

Table 3: Global Pittsburgh Sleep Quality Index scores before and after self-care intervention*

Discussion

This randomized-controlled study was designed to evaluate the effectiveness of a self-care intervention based on sleep hygiene practices, healthy nutrition emphasized on necessary diet changes to get a good night"s sleep, and physical activity on quality of sleep in post-CABG patients. Our study findings support our hypothesis that self-care intervention would improve the quality of sleep in post-CABG patients. The results of this study showed a statistically significant difference between the sleep quality before and after the intervention (p=0.001), suggesting that applying self-care intervention in post-CABG patients improved their sleep quality.

The improvements in the quality of sleep in post- CABG patients observed in this study were also consistent with changes obtained with other nonpharmacological interventions which had a positive effect on improved quality of sleep in patients with cardiovascular disease, including nurse-led intervention,[5] aromatherapy with lavender oil,[15] massage therapy,[16,17] jaw relaxation,[18] acupressure,[19] supervised exercise training program,[20] and CD-based relaxation program.[21] All of the a forementioned non-pharmacological interventions led to improved quality of sleep in patients with cardiovascular disease. However, negative aspects of most of these methods included the requirement of equipment, increased physiotherapist work force, and an increased cost of treatment. The self-care interventions, as described in our study, were safe and well-tolerated, irrespective of any equipment or device used.

Furthermore, our study is consistent with a previous study carried out by Ranjbaran et al.[2] on sleep quality in patients after CABG, which was an interventional study using PRECEDE-PROCEED model. The authors reported that addition of an intervention based on the PRECEDE-PROCEED model to the cardiac rehabilitation program might further improve the sleep quality of patients.

Similar to our study, as a non-pharmacological treatment for symptom management in post-cardiac surgery patients, Akinci et al.[22] showed that posture and relaxation training had beneficial effects on sleep quality, reducing sleep medication use, alleviating dyspnea and pain, and increasing quality of life. On the other hand, the study of Atalan et al.[23] showed that the prevalence of sleep disturbances, particularly excessive daytime sleep or poor sleep, were significantly more common in patients with delirium 12 months after surgery. Hence, applying interventions for improving quality of sleep such as self-care interventions, as in our study, may contribute to reduced delirium rates in post-CABG patients.[23]

Furthermore, in the study of Akinci et al.[22] investigating the effects of posture and relaxation training on sleep in patients with cardiac surgery demonstrated that, in the postoperative period, sleep medication use might cause side effects such as respiratory depression, anxiety, cognitive impairments, and weakness. This may also affect the compliance of the patient to the rehabilitation program.

The results of our study provided new insights into how self-care interventions based on; sleep hygiene practices, healthy nutrition emphasized on necessary diet changes to get a good night"s sleep, and physical activity, can contribute to improve the quality of sleep and, consequently, to decrease sleep medicationsrelated side effects such as respiratory depression, anxiety, cognitive impairments, and weakness in post- CABG patients.

Nonetheless, there are some limitations to this study. First, the participants in our study were recruited only from one hospital. Second, the duration of intervention in our study was relatively short. Therefore, we recommend further multi-center studies with longer intervention duration to confirm our findings.

In conclusion, despite the high rate of sleep disorders among post-coronary artery bypass grafting patients, using practical and safe methods such as self-care interventions based on sleep hygiene practices, healthy nutrition emphasized on necessary diet changes to get a good night"s sleep, and physical activity can contribute to improved quality of sleep, comfort level, and quality of life among these patients. Traditionally, poor sleep quality prompts physicians to prescribe drugs for patients which may be associated with certain adverse effects, such as memory impairment, drug resistance, dependence, and addiction. Our study results suggest that self-care interventions based on sleep hygiene practices, healthy nutrition emphasized on necessary diet changes to get a good night"s sleep, and physical activity can be useful to decrease sleep disturbances in this patient population.

Acknowledgments
This article was extracted from a master"s thesis. The authors would like to express their thanks to the patients who participated in this research.

Declaration of conflicting interests
The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Funding
The authors received no financial support for the research and/or authorship of this article.

References

1) Yazdi Z, Loukzadeh Z, Moghaddam P, Jalilolghadr S. Sleep Hygiene Practices and Their Relation to Sleep Quality in Medical Students of Qazvin University of Medical Sciences. J Caring Sci 2016;5:153-60.

2) Ranjbaran S, Dehdari T, Sadeghniiat-Haghighi K, Majdabadi MM. Poor Sleep Quality in Patients after Coronary Artery Bypass Graft Surgery: An Intervention Study Using the PRECEDE-PROCEED Model. J Tehran Heart Cent 2015;10:1-8.

3) Koren D, Dumin M, Gozal D. Role of sleep quality in the metabolic syndrome. Diabetes Metab Syndr Obes 2016;9:281-310.

4) Tel H, Tel H, Esmek M. Quality of sleep in hemodialysis patients. Dial Transplant 2007;36:479-84.

5) Mousavi Malek N, Zakerimoghadam M, Esmaeili M, Kazemnejad A. Effects of nurse-led intervention on patients" anxiety and sleep before coronary artery bypass grafting. Crit Care Nurs Q 2018;41:161-9.

6) Rosenfeldt F, Braun L, Spitzer O, Bradley S, Shepherd J, Bailey M, et al. Physical conditioning and mental stress reduction--a randomised trial in patients undergoing cardiac surgery. BMC Complement Altern Med 2011;11:20.

7) Kaya U, Çolak A, Becit N, Ceviz M, Koçak H. Intraoperative transit-time flow measurement in on-pump coronary artery bypass graft surgery: Single center experience. Turk Gogus Kalp Dama 2018;26:167-76.

8) Greve H, Pedersen PU. Improving sleep after open heart surgery: effectiveness of nursing interventions. J Nurs Educ Pract 2016;6:15-25.

9) Machado FS, Souza RCS, Poveda VB, Costa ALS. Nonpharmacological interventions to promote the sleep of patients after cardiac surgery: a systematic review. Rev Lat Am Enfermagem 2017;25:e2926.

10) Barroso LMM , Brito DMS , Galvão MTG , Oliveira Lopes MVO, Utility of the self-care theory to assist the bearer of human immunodeficiency virus/acquired immunodeficiency syndrome. Acta Paul Enferm 2010;23:562-7.

11) Malekshahi F, Aryamanesh F, Fallahi S. The effects of massage therapy on sleep quality of patients with end-stage renal disease undergoing hemodialysis. Sleep and Hypnosis 2018;20:91-5.

12) Del Rio João KA, Becker NB, de Neves Jesus S, Isabel Santos Martins R. Validation of the Portuguese version of the Pittsburgh Sleep Quality Index (PSQI-PT). Psychiatry Res 2017;247:225-9.

13) Ghavami H, Akyolcu N. The impact of lifestyle interventions in breast cancer women after completion of primary therapy: a randomized study. J Breast Health 2017;13:94-9.

14) Farrahi Moghaddam J, Nakhaee N, Sheibani V, Garrusi B, Amirkafi A. Reliability and validity of the Persian version of the Pittsburgh Sleep Quality Index (PSQI-P). Sleep Breath 2012;16:79-82.

15) Moeini M, Khadibi M, Bekhradi R, Mahmoudian SA, Nazari F. Effect of aromatherapy on the quality of sleep in ischemic heart disease patients hospitalized in intensive care units of heart hospitals of the Isfahan University of Medical Sciences. Iran J Nurs Midwifery Res 2010;15:234-9.

16) Khosravi A, Bolourchifard F, Ikhani M, Pourhoseingholi MA. The effect of massage therapy on sleep quality in cardiac care unit patients. Biosci Biotech Res Comm 2017;10:645-51.

17) Nerbass FB, Feltrim MI, Souza SA, Ykeda DS, Lorenzi- Filho G. Effects of massage therapy on sleep quality after coronary artery bypass graft surgery. Clinics (Sao Paulo) 2010;65:1105-10.

18) Kashi MS, Goyaghaj NS, Hoseini MA, Shahbolaghi FM, Bakhshi E. Evaluation of the effect of jaw relaxation on sleep quality in patients with myocardial infarction. Medical - Surgical Nursing Journal 2016;4:49-55.

19) Yaghoubi A, Golfeshan E, Azarfarin R, Nazari A, Alizadehasl A , Ehasni A. Effects of acupressure on sleep quality after coronary artery bypass surgery. Iranian Heart Journal 2017;18;28-34.

20) Suna JM, Mudge A, Stewart I, Marquart L, O'Rourke P, Scott A. The effect of a supervised exercise training programme on sleep quality in recently discharged heart failure patients. Eur J Cardiovasc Nurs 2015;14:198-205.

21) Johansson A, Adamson A, Ejdebäck J, Edéll-Gustafsson U. Evaluation of an individualised programme to promote self-care in sleep-activity in patients with coronary artery disease -- a randomised intervention study. J Clin Nurs 2014;23:2822-34.

22) Akıncı B, Yeldan İ, Bayramoğlu Z, Belhhan Akpınar T. The effects of posture and relaxation training on sleep, dyspnea, pain and, quality of life in the short-term after cardiac surgery: a pilot study. Turk Gogus Kalp Dama 2016;24:258-65.

23) Atalan N, Sevim ME: Postoperative delirium associated with prolonged decline in cognitive function and sleep disturbances after cardiac surgery. Turk Gogus Kalp Dama 2013;21:358-63.