Background: Nurses have experienced several stressors, the most important of which are increased workloads, long shifts, patients' negative results, some patients not responding to treatment, death at high rates, late detection of disease cases, lack of social support system, and limited typical coping.

Aim: The purpose of this study is to assess the effectiveness of mindfulness meditation for clinical nurses to improve perceived stress and somatic symptoms and pro-inflammatory factors. Among Jordanian clinical nurses.

Methodology: The study will be conducted using a post-test randomized controlled experimental design. The study data will be collected using a self-report questionnaire and blood sampling from 102 nurses in in King Abdullah hospitals at baseline and at the end of intervention. Data were analyzed using the Statistical Package for Social Science (SPSS), Version 26.

Introduction

The nursing profession has historically been associated with significant chronic stress due to frequent exposure to various work-related stressors. These include psychological or physical violence in the workplace, coping with patient deaths, staff shortages, and a high patient load. The pandemic has added additional pressures and stressors, including dealing with emergency patients, fear of exposure to the virus, increased working hours, imbalance between work and personal life, disruption of family life, and inability to adapt to a rapidly changing work environment. These unprecedented situations require nurses to work long hours with more limited resources, which lead to sever level of chronic stress.

Some nurses demonstrate resilience in the face of stress. However, most experience prolonged stress that dysregulate physiological functions and reduce physical and psychological health. According to Yaribeygi, et al. (2017) psychological stress is associated with the activation of several body systems, including the hypothalamic pituitary-adrenal axis and the sympathetic nervous system. The activation of these two pathways results in elevated cortisol and catecholamines. Although the mechanism is still not fully understood, chronic stress results in prolonged, excessive production of cortisol, causing chronic release of pro-inflammatory factors such as InterLeukine-6 (IL-6) and TNFα. Such a chronic increase of proinflammatory markers in healthy individuals is generally known as low-grade inflammation, which is associated to several chronic illness such as cardiovascular disease, type 2 diabetes, metabolic syndrome and major depression. Studies have revealed that persistent workplace stress lead to increased inflammatory activity in healthcare professionals with unsatisfied working conditions.

The elevated cortisol and catecholamines also puts nurses at increased risk of developing somatic symptoms, known as physical complaints, that cannot be explained by medical condition, mental disorder, or substance abuse. These complaints are often associated with psychological stress and may involve sleep problems, digestive problems, heart disease, palpitations, headache, weight gain and memory and concentration and muscle tension. A recent systematic review investigating the prevalence of somatic symptoms during the COVID-19 pandemic showed that such symptoms, including shortness of breath, dyspnea, palpitations, and pain, were reported by 7.4% to 67% of patients, healthcare workers, and the general population. Also, a study revealed that the overall prevalence rates somatic symptoms among nurses during COVID-19 pandemic was 50%. Such symptoms affect negatively nurses' quality of life and job performance, resulting in increased errors in patient care.

The high prevalence of somatic symptoms and low-grade inflammation among healthcare professionals, including nurses, indicates unmet needs within this population. Addressing these needs requires implementing preventive strategies to enhance mental resilience, particularly for high-risk individuals such as nurses. Mindfulness is one of the most important methods used in psychotherapy, which is strongly associated with promotion physical and psychological well-being, it is an effective method for reducing stress and improving health. The practice of mindfulness originally began in Asian culture due to meditative practices in Buddhist philosophy and eastern spiritual traditions; where it emphasized the value of presence, non-exaggeration, and experience acceptance. In the 1970s and 1980s, mindfulness began to be used in Western countries, and it gradually developed into one of the most important techniques in contemporary psychotherapy. In recent years, the practice of mindfulness has been widely applied in both clinical and non-clinical settings

. Several studies support the potential benefits of MBI on psychological health among nurses. Duarte and Pinto-Gouveia reported that an abbreviated MBI resulted in significant improvement in compassion fatigue, burnout, stress, life satisfaction and self-compassion in oncology nurses. In a systematic review conducted by Chiappetta et al., MBI has been found to significantly decrease stress, burnout, anxiety, and depression, and improve self-compassion and quality of life among healthcare professionals. Similarly, Lomas et al. in their systematic review supported these results, indicating that MBI significantly reduced anxiety, depression, stress, and overall well-being in nurses. Lin et al. conducted in randomized control trial and found that an eight-week MBSR program reduced stress and negative affect while increasing positive affect and resilience among Chinese nurses. Two other systematic review studies by Sulosaari et al. and Ramachandran et al. found that MBI significantly improved psychological well-being, resilience, and quality of life, while reducing stress, depression, and burnout among nurses.

However, rare studies examined the effect of such intervention on nurses' physical health such as somatic symptoms and inflammation. MBI, as a holistic approach, has been found to improve a wide range of health outcomes in different healthy and ill populations including somatic symptoms and proinflammatory markers. The mechanism underlying the effect of mindfulness intervention on somatic symptoms and inflammatory biomarkers can be explained by the Cognitive Reappraisal Model. According to this model, the effects of mindfulness practices on health outcomes are postulated to be mediated by improvement in trait mindfulness and emotion regulation skills. Frequent mindfulness practice boosts the mental capacity of mindfulness trait, known as present-moment awareness and non-judgmental observation over thought and feelings. Such mental capacity helps people become aware of and detach from the stressful thoughts and emotions by enabling cognitive reappraisal as an emotion regulation skill. This is the process by which people can re-interpret stressful events in less negative ways, resulting in lower perceived stress levels. By alleviating perceived stress through cognitive reappraisal, mindfulness intervention can improve the physiological responses associated with stress, such as the activation of the hypothalamic-pituitary-adrenal (HPA) axis and the release of proinflammatory biomarkers.

Research have supported the hypotheses of the Cognitive Reappraisal Model indicating the mindfulness intervention can potentially reduce somatic symptoms and inflammatory biomarkers (e.g. interleukin 6 and TNF-alpha) by reducing perceived stress. However, to the best of our knowledge, these effects have not been examined among nurses in Jordan. Thus, this study aimed to examine the effect of mindfulness intervention on perceived stress, somatic symptoms, proinflammatory biomarkers such as interleukin 6 and TNF alpha.

Methods Design This was an experimental study using pretest post-test randomized controlled design. This design is described as a plausible tool in terms of the control on extraneous variables using various strategies, including manipulation, control group, and random assignment. Participants were randomly assigned into the experimental and control groups. Researchers who are not involved in the recruitment process and patient assessment, were randomly assign the participants to the intervention group or the control group, using a simple 1:1 computer-generated sequence.

Sample and setting The hospital can accommodate 750 beds, but in an emergency, that number may be raised to 900. Participants who were having psychiatric illnesses, disorders of the immune system (e.g., immunodeficiency or autoimmune disorders), and current infections and taking anti-inflammatory or antimicrobial medications were excluded.

G*Power software version 3.1 was used to calculate the required sample size. Based on an independent t-test, with an alpha level of 0.05, a power of 0.8, and a moderate effect size of 0.5, the required sample size was determined to be 102 participants.

Intervention The experimental group received eight 60-minute weekly sessions of MBI over eight weeks in a private and quiet room at the hospital, according to Smith's (2005) recommendation. The study intervention was an audio based MBI sent to them by the WhatsApp application. It is a free, self-paced program developed by a study researcher based on the Smith's (2005) protocol. This study researcher was an experienced practitioner with a Ph.D. degree in nursing and received extensive stress management training, including MBI at a Psychology Department at a university in the United States 10 years ago. Since then, he has been practicing the MBI daily. The audio recording of the MBI was evaluated and validated for the clarity of voice and the MBI content by two psychologists who are experts in MBI.

However, these eight weekly sessions were conducted by one of the study researchers to explain the rationale and procedures of MBI including a demonstration of the entire MBI protocol for the participants in the experimental group. He was also present during the delivery of MBI session to confirm and facilitate the administration of the MBI sessions and answer any participants' questions. This study researcher has a master's degree in nursing and received extensive MBI training. The participants in the experimental groups were encouraged not to share any information regarding the MBI with anyone during the study.

The theory-based program (Smith, 2005) includes the ABC standardized versions of MBI (Smith, 2005), described as follows:

• Meditation of the body (Body sense meditation): Individuals pay attention in the present moment without judgment.
• Meditation of the body (Rocking meditation): Individuals allow themselves to gently rock back and forth in their chairs, effortlessly and quietly, while paying mindful attention to the gentle, silent motion of the rocking
• Meditation of the body (Breathing meditation): Individuals allow their breathing to flow naturally, free and easy, while simply focusing on the rhythm of the breath as it moves in and out.
• Meditation of mind (Mentra meditation): Individuals allow a calming word, like 'peace,' to gently enter their minds, like an echo in the distance, while quietly and effortlessly focusing as the word repeats over and over
• Meditation of mind (visual Image): Individuals visualize a simple spot of light, such as a candle flame or a star, and quietly focus their attention on it.
• Meditation of sense (External image): Individuals slowly open their eyes halfway and gently gaze at a certain object (e.g. candle) in front of them
• Meditation of the senses (A sound): Individuals choose a quiet, continuous sound and gently focus their attention on it
• Open monitoring (Mindfulness): Nurses quietly observe, acknowledge, and release every internal and external stimulus-such as thoughts, feelings, sensations, sounds, and ideas-that enters their awareness. They refrain from analyzing, resisting, or trying to manage these experiences and do not concern themselves with the connections between each stimulus. Instead, they simply allow each stimulus to arise and fade away, patiently waiting for the next one.

Participants in the control group were not asked to do anything during the study, except their traditional practices. However, mindfulness meditation was provided to them after the study.

Data collection and Ethical consideration Following IRB approval, one of the study researchers contacted the hospital administrators to seek permission to conduct the study. Once approval was granted, the nurses were approached in person, and the study's purpose was explained to them. Those who agreed to participate were asked to sign a consent form. Participants' confidentiality and anonymity were strictly maintained. A researcher not involved in recruitment or patient assessment then randomly assigned participants to either the intervention or control group using a simple 1:1 computer-generated sequence. The mindfulness-based intervention (MBI) schedule was provided to participants in the experimental group, aligned with their work schedules.

Baseline and post-intervention measurements were conducted at the hospital by a researcher (nurse). To minimize measurement errors due to variations in data collection, self-reported measures were completed after the objective measures, such as biological markers, to reduce stress-related biases. All measurements for both the intervention and control groups were taken under consistent conditions, including room temperature and environment, by a well-trained nurse with a master's degree in nursing. The ELISA protocol for blood sampling was meticulously followed, and neurotransmitter and hormone levels were measured at 8 a.m. for all participants, who were seated during testing.

Statistical Analysis Data were analyzed using the Statistical Package for Social Science (SPSS), Version 26. Descriptive statistics were used to describe the study participants as appropriate. For instance, frequency and percentage were used to describe the categorical variables, while mean and standard deviation (SD) were used to describe the continuous variables. Also, the baseline statistical equivalence between the study groups on the dependent and sociodemographic variables was evaluated using independent t-tests. Dependent t-tests were used to examine if there were statistically significant changes between the pretest and posttest in each study group. Finally, independent t-tests were used to examine if there was a statistically significant difference between the experimental and control group at the end of the intervention.

Inclusion Criteria:

• Nurse working in the hospital in Jordan
• Being at least 21 years old
• Having a smartphone
• Being able to read and write in English

Exclusion Criteria:

• Having psychiatric illnesses
• Having disorders of the immune system (e.g., immunodeficiency or autoimmune disorders) and current infections.
• Taking anti-inflammatory or antimicrobial medications

Due to the ethical constraints

The outcome assessor will be blinded to the participants' group assignment