The study aims to investigate how mindfulness-based intervention (MBI) impacts trait mindfulness, cognitive reappraisal, expressive suppression and quality of life in patients with end-stage renal disease (ESRD) undergoing hemodialysis.

A Randomized controlled trial will be conducted with patients diagnosed with ESRD and undergoing hemodialysis treatment. Participants selected using a convenience sampling method will be randomly assigned into the intervention group (n=52) who received MBI, and the control group (n=52) who received a similar intervention after the study. The intervention involves a 30-minute MBI introduced three sessions per week during hemodialysis sessions over five weeks. Outcome measures included the Mindful Attention Awareness Scale (MAAS) to assess trait mindfulness, the Emotion Regulation Questionnaire (ERQ) for cognitive reappraisal and behavioral suppression, and the Kidney Disease-related Quality of Life Questionnaire for quality of life. Data were collected at baseline and post-intervention.

Chronic kidney disease (CKD) is a comprehensive term encompassing various stages of diminishing kidney function. Kidney damage or sustained estimated glomerular filtration rate (eGFR) of less than 60 ml/min per 1.73 square meters sustained for three months or more are hallmarks of chronic kidney disease (CKD). Individuals affected by CKD commonly encounter symptoms such as fatigue, headaches, weakness, nausea, vomiting swelling in the legs and feet occurs frequently. Challenges in concentration also manifest. If left untreated, CKD can lead to serious complications such as fluid retention high blood pressure, anemia bone disease. Effective management of CKD, such as regular monitoring, lifestyle changes, medication, and other medical interventions remains pivotal in mitigating its progression and associated complications. Left unaddressed, CKD has the potential to advance to end-stage renal disease (ESRD). This necessitates life-saving interventions like dialysis or kidney transplantation (Khusainova et al., 2023; Vaidya & Aeddula, 2023).

ESRD has emerged as a leading global cause of death, standing out as one of the few non-communicable diseases with a rising mortality rate over the past two decades. Over 800 million people worldwide suffer from ESRD, a degenerative illness that affects more than 10% of the population (Kovesdy, 2022). In the United States, ESRD exhibits an incidence rate of 390.2 cases per million and a prevalence rate of 242 cases per million. Black and Hispanic patients had rates of ESRD that were 3.4 and 1.5 times higher, respectively, then those of the general population. Individuals aged 65 and older are at the highest risk of developing ESRD, accounting for about three-quarters of all cases (Johansen et al., 2021).

The prevalence of chronic kidney disease (CKD) is highest in low- and middle-income nations, where controlling its effects is difficult (Kovesdy, 2022). In Jordan, the Jordanian Ministry of Health (MOH) (2020) states that the total number of patients who were registered and treated in the Jordanian Renal Registry will be 7747 by the end of 2020, of which 7290 are Jordanians (94. 1%) and 457 are non-Jordanians (5.9%). The number of Jordanian patients enrolled and hospitalized for ESRD in 2020 was 7290, while the number of new ESRD cases in 2020 was 975, with 898 (92.1%) Jordanians and 77 (7. 9%) non-Jordanians (Jordanian Ministry of Health, 2020).

Renal replacement therapies become necessary when kidneys can no longer perform essential functions ensuring that waste products and excess fluid are removed from the body adequately (Vaidya & Aeddula, 2023). Among renal replacement therapies, hemodialysis is a key therapy that extends life by excreting or removing harmful waste products of metabolism from the circulatory system of humans. Of patients with ESRD, hemodialysis accounts for 70.7% of treatment, with kidney transplantation accounting for 29.3% of cases in the United States (Johansen et al., 2021). In Jordan, the total number of dialysis machines (944) in all units was distributed as follows: 441 (47%) machines in Ministry of Health units, 86 (9%) machines in Royal Medical Service (RMS) units, 32 (3%) machines in university hospitals, and 385 (41%) machines in private sector hospitals. Of the 7290 patients with prevalent ESRD, 3318 patients (45.5%) were treated in dialysis units of the Ministry of Health, 1424 patients (19.5%) in RMS dialysis units, 191 patients (2.6%) in dialysis unit of the University Hospital, and 2,357 patients (32.3%) were treated in private dialysis units.

Despite its role in extending the lives of patients with ESRD, research indicates that individuals undergoing hemodialysis experience a lower quality of life (QOL) compared to those with other chronic illnesses (Dehghan et al., 2020). QOL is a widely recognized concept that reflects an individual's perception of their physical health, psychological well-being, independence, social relationships, beliefs, and personal values (Madadkar & Basiri, 2018). Patients with ESRD undergoing hemodialysis face numerous physical symptoms that limit their daily functioning and threaten their overall physical health. Also, the treatment itself is physically and mentally demanding, as patients typically receive hemodialysis 2 to 3 times per week for 4 to 5 hours per session, which significantly impacts their psychosocial well-being. The combined effects of the illness and the treatment create a substantial burden, jeopardizing the overall QOL for those undergoing hemodialysis (Lim & Lee, 2022).

Patients on hemodialysis who experience a decline in QOL may experience effects on many aspects of their lives, including a diminished capacity to do daily tasks (Madadkar & Baser, 2018). Furthermore, poor QOL contributes to dependency, sadness, social isolation, a reduction in daily activities, and a rise in the financial burden (Dehghan et al., 2020). The work, familial, and social status of individuals with ESRD also altered because of changes in their quality of life (Adamopoulou et al., 2019; Nguyen et al., 2022) Hence, effectively managing diminished QOL and addressing its underlying symptomatic causes are crucial for enhancing clinical outcomes in individuals undergoing hemodialysis. Both pharmacological and non-pharmacological approaches are employed to address these issues. However, a significant number of patients continue to experience psychosomatic symptoms even with the utilization of medications. Presently, there is a growing focus on integrating non-pharmacological and complementary therapies within healthcare systems for improved outcomes (Madadkar & Basiri, 2018). Methods in complementary medicine typically carry minimal side effects and risks, making them suitable for standalone use or in conjunction with other approaches (Kaplan Serin et al., 2020). These therapies, known for their holistic nature, are employed to enhance both the physical and mental well-being of patients (Nguyen et al., 2022).

Mindfulness-based intervention (MBI) is a common and effective complementary therapy that has widespread use in a variety of contexts, groups, and applications (Howarth et al., 2019). MBI teaches people how to cultivate a non-judgmental awareness that is oriented toward the present moment. This intervention has shown potential for treating a number of mental health conditions, including anxiety and depression, as well as persistent physical illnesses (Rigas et al., 2022). In hemodialysis settings, MBI has been found to be effective in improving multiple psychosomatic symptoms such as perceived stress, emotion regulation, sleep disturbances, stress, depression, and anxiety in patients with ESRD worldwide (Razzera et al., 2021). Also, there is initial evidence in the literature supporting the beneficial effect of MBI on quality of life in such patients (Alhawatmeh et al., 2022).

There have been several studies supporting the potential positive effects of MBI on psychophysical health and overall QOL among patients undergoing hemodialysis. However, the mechanisms underlying the beneficial effects of MBI on health among such patients have been rarely studied. In recent years, there has been an increasing interest in identifying the underlying mechanisms of MBI because of growing evidence of its benefits on mental disorders and physical well-being (Gu & Zhu, 2022; Zhang et al., 2021). Several theoretical approaches have been suggested to identify how MBI affects quality of life.

The mechanisms of MBIs have been hypothesized to involve improvements in trait mindfulness, which then facilitate gains in emotion regulation skills, thereby culminating in improved quality of life outcomes (Niazi & Adil, 2017; Shapero et al., 2018; Teper & Inzlicht, 2013; Zhang et al., 2021). T. Indeed, this view is supported by evidence from several studies (Niazi & Adil, 2017; Shapero et al., 2018; Teper & Inzlicht, 2013; Zhang et al., 2021). In the context of the above-outlined framework, the major two strategies for emotion regulation that are mostly studied include cognitive reappraisal and behavioral suppression. Research showed that MBIs enhance cognitive reappraisal, described as reinterpretation of stressful situations in a positive way to lower emotional distress. Evidence on the effectiveness of MBI in behavioral suppression, understood as the suppression of emotional expressions, remains scant and ambiguous. Though findings might be mixed, some studies do indicate a possible positive influence of MBI on cognitive reappraisal, but when it comes to behavior suppression, their effect is negligible or non-significant. This may be related to the fact that the basic mechanism of MBI tends to improve trait mindfulness through present-moment awareness and acceptance rather than suppression of emotions.

Despite these advances, evidence is still developing, and more research needs to be done in order to understand how MBI relate to disparate strategies for regulating emotions. Importantly, such processes have not as yet been investigated empirically in hemodialysis patients-a population experiencing emotional burdens and low quality of life. To the best of our knowledge, no study has yet systematically investigated how MBI would affect emotion regulation processes, namely cognitive reappraisal and expressive suppression, in this patient population. Furthermore, the wider effects of MBI on trait mindfulness and quality of life among hemodialysis patients remain largely unaddressed. The present study therefore tried to fill these gaps in knowledge by assessing the impacts that MBI have on trait mindfulness, cognitive reappraisal, and expressive suppression in hemodialysis patients. It further aimed to explore the impact of MBI on quality of life, thereby offering insight into possible therapeutic benefits that may be gained from the practice of MBI in this highly specific clinical setting.

Methodology

Design An experimental study with a pretest-posttest, randomized, parallel control group design was employed. Participants who were selected using a convenience sampling method were randomly assigned into the intervention group who received MBI, and the control group who received the similar intervention after the study. The intervention involved 30-minute MBI introduced three sessions per week during hemodialysis sessions over a five-week period. The study data were collected at baseline and the end of the intervention.

Setting and Sample This study was conducted at a military hospital Military in the dialysis department, which contains 58 dialysis machines. In this department, there are three sessions per day throughout the week, with three dialysis sessions for each patient per week. The dialyis department receives approximately 174 patients daily, divided into three sessions throughout the day. This dialysis department is considered as the largest dialysis unit in the Middle East, with a monthly capacity of between 2,200 and 2,240 patients (Shqeirat et al., 2021).

Determination of Sample Size G*power 3.1.9.4 was used to calculate the sample size. Given an independent t-test, a medium effect size of 0.5, an alpha of 0.05, and a power of 0.8, the calculated sample size was 102. Taking in consideration an attrition rate of 15 % (Alhawatmeh et al., 2022), the required sample size is 117 participants. To be more conservative, 3 participants were added, resulting in a final required sample size of 120 participants. Of the 170 assessed for eligibility, 120 participants were deemed eligible and agreed to participate. Of these, 104 completed the study and their data were analyzed. The remaining 16 participants chose to withdraw from the study before baseline data collection due to health issues (See Figure 1).

Intervention In the present research, the standardized, theory based MBI was introduced to the experimental group (Smith, 2005). This 30-minute protocol involves a series of activities, including paying attention to and being aware of breath, body sensations, thoughts, and sounds without judgment. This protocol is a widely recognized and utilized method due to its simplicity and accessibility, making it an ideal choice for this study (Alhawatmeh et al., 2022; Smith, 2005).

Smith's (2005) MBI protocol comprises six components:

The MBI protocol developed by Smith (2005) consists of six parts:

1. Practicing mindfulness of the breath by inhaling deeply and slowly, paying attention to the movement of air.
2. Practicing body awareness by paying attention to all of the senses the body has from head to toe and recording any sensations you experience.
3. Being aware of the thought by paying attention to the mind as ideas and thoughts arise and pass, noting them, letting them go, and returning to the mind again and again.
4. Paying attention to sounds without passing judgment on them, observing them, letting them go, and waiting still are examples of mindfulness of sound.
5. Walking mindfully by visualizing yourself on a road devoid of obstacles. Just picture the location of each step without considering where to go.
6. Full meditation: by opening one's eyes and living mindful of the world of the moment, when noting something (sound, thought, sensation, etc.), the individual must let it go and wait for what comes next.

Participants in the experimental group completed three weekly sessions of MBI for five weeks during their hemodialysis treatments (Alhawatmeh et al., 2022). Participants were provided with audio recordings of the MBI protocol, which they could practice during hemodialysis sessions. These recordings were delivered via email and WhatsApp, depending on their preference. This audio recording was developed based on the Smith's protocol by a certified study researcher who had a higher degree in nursing and extensive experience in practicing and delivering MBIs. The audio recording was validated by two psychologists who have good experience of MBIs. The researcher supervised the delivery of the MBI, manage any interruption and protect privacy during the MBI delivery and make sure they could practice successfully. Participants were encouraged to practice the MBI at home during the five-week study period, although it was not mandatory. Participants in both groups were instructed to maintain their usual routines before the study and to avoid seeking psychiatric or alternative treatments for mood improvement. They were also asked to inform the researcher if they decided to pursue such treatments during the study period.

A face-to-face educational session prior to the intervention was performed in order to enhance participants' understanding of the intervention. Accordingly, there was an additional 2-hour education session in which the participants in the experimental group had detailed information from the researcher regarding the purpose and method of intervention. The session included a thorough walkthrough of the entire intervention process; participants were introduced to the basics of the MBI program. The participants were encouraged to ask questions and engage in discussions to ensure a clear understanding of the intervention. The researcher gave an examples to illustrate the potential outcomes and benefits of the intervention. Overall, the pre-intervention training session aimed to establish a solid foundation of knowledge and create a sense of confidence among the experimental group's participants regarding the intervention's effectiveness and implementation (Alhawatmeh et al., 2022).

The control group did not receive any intervention from the researcher. However, upon completion of the study, the control group participants were provided with and given an explanation of the audio recordings of the intervention protocol.

Procedure After getting the IRB approval, the hospital managers were contacted by a study researcher to obtain approval for conducting the study in their institution. When approved, the researcher contacted patients in person to explain the purpose and procedure of the study. Patients agreeing to participate in the study were requested to sign the informed consent form. Then, the participants randomly allocated into the experimental group and control group using a cluster random assignment to avoid contamination. To conduct this assignment strategy, a list of patients who met the study criteria was compiled, including their shifts (A, B, and C). Patients received their hemodialysis sessions three times per week, either on Sunday, Tuesday, and Thursday (STT), or on Monday, Wednesday, and Saturday (MWS). This setup resulted in six clusters (two shifts per week (STT or MWS) × three shifts (A, B,and C) per day). The clusters were defined based on the combination of hemodialysis days and shifts: 1) STT Shift A, 2) STT Shift B, 3) STT Shift C, 4) MWS Shift A, 5) MWS Shift B, and 6) MMWS Shift C. All six clusters, each comprising 20 participants as determined during the sample size calculation, were first listed. Subsequently, these clusters were randomly assigned to either the experimental group or the control group. Randomization was achieved using a random number generation method to ensure an unbiased allocation. This randomization strategy was performed by an independent researcher who did not participate in the recruitment process and remained blinded to the participant list.

After randomization, the study sociodemographic and dependent variables were measured at baseline in the hemodialysis unit before starting the intervention. At the end of the intervention (after five weeks of the actual MBI training), the study dependent variables were measured again. A well-trained research assistant who would not be involved in other study parts collected the data. This research assistant is an experienced nephrology registered nurse. All measurements were privately taken in similar situations (e.g, sitting position) and environments (e.g temperature) in the hemodialysis unit. Nobody was present when they filled out the questionnaire.

Data Analysis The statistical package for social science (SPSS) version 25 was used to analyze data. Descriptive statistics was used to describe the study data as appropriate. Frequency and percentage was used to describe the categorical variables while mean and standard deviation was used to describe the continuous variables. The assumptions for the t-test were tested to confirm the validity of the study results. Normality was examined using histograms, the Shapiro-Wilk test, and by evaluating skewness and kurtosis values. Homogeneity of variance was checked using Levene's test. These checks ensured that the data sufficiently met the necessary assumptions for performing the t-tests. Independent t-tests was used to examine any baseline differences between the study groups on the continuous sociodemographic variables and main study outcomes. Chai square tests were used to examine any baseline differences between the study groups on the categorical sociodemographic variables. A dependent t-test was used to assess changes in the mean scores of the outcomes between the pre-test and post-test within each study group. Finally, independent t-tests were used to examine the significant differences between the study groups at end of the intervention.

Ethical Considerations The Institutional Review Board (IRB) approved the proposed study (Approval Number: 136-2024). Participants who agreed to participate in the study were asked to sign a consent form that described the purpose and scope of the research. They confirmed that they had the freedom to reject participation in the study and that such rejection would not affect the care they received. They were assured that the research data would be stored in a secure location in a locked cabinet accessible only to the researcher, with numbers replacing their names to avoid their personal identification. No patients were excluded from the trial because of their gender, race, or nationality. During the intervention, if any patient felt dizzy or uncomfortable, the intervention was stopped, and the attending physician was informed immediately.

Inclusion Criteria:

• Patients with ESRD undergoing hemodialysis at least three sessions a week
• Being at least 18 years old
• Having a smartphone
• Being capable of reading and writing in Arabic

Exclusion Criteria:

• Patients under psychotherapy or taking regular psychopharmacological and analgesic treatment

Because of ethical restrictions