Volume 28, Issue 1 (Winter 2021)                   Intern Med Today 2021, 28(1): 70-85 | Back to browse issues page

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Akbarian M, Mohammadi Shirmahleh F, Borjali A, Hasanabadi H, Abolghasemi S. Effect of Acceptance and Commitment Therapy on Depression, Chronic Fatigue, and Pain Intensity in Patients with Fibromyalgia Syndrome: A Study with Expectancy Effect. Intern Med Today 2021; 28 (1) :70-85
URL: http://imtj.gmu.ac.ir/article-1-3684-en.html
1- Department of Health Psychology, Karaj Branch, Islamic Azad University, Karaj, Iran.
2- Department of Health Psychology, Karaj Branch, Islamic Azad University, Karaj, Iran. , m_mohammadi1352@yahoo.com
3- Department of Clinical Psychology, Faculty of Psychology and Educational Science, Allameh Tabataba'i University, Tehran, Iran.
4- Department of Educational Psychology, Faculty of Psychology and Educational Science, Kharazmi University, Tehran, Iran.
5- Department of Rheumatology, Faculty of Medicine, Tehran North Branch, Islamic Azad University of Medical Sciences, Tehran, Iran.
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Fibromyalgia Syndrome (FMS) is a chronic disorder characterized by widespread musculoskeletal pain, which adversely affects functioning in psychological and social aspects of life [
1]. The worldwide FMS prevalence is estimated to be 2% in the general population, with a prevalence of 61%-90% in women. The pain caused by FMS is different because it is diffuse and migratory and can spread to various parts of bod chronically and widely [2]. There is an evidence of psychiatric comorbidities in FMS patients, including depression, anxiety, obsessive-compulsive disorder, and post-traumatic stress disorder, which may be due to their same underlying construct. On the other hand, FMS patients have limited flexibility, which may be due to depression, anxiety, and other psychiatric disorders [3]. The stress that comes from a lack of ability to control pain, along with catastrophic thinking can result in depression which can lead to lower pain tolerance [4, 5]. FMS sometimes overlaps with other diseases such as chronic fatigue syndrome. FMS is associated with chronic pains such as migraine and seizure-related headaches and temporomandibular disorders [6]. Fatigue is an unpleasant feeling that disrupts a person’s psychological and physical functioning and prevents from performing daily tasks [7]. Depression can be treated by antidepressants, psychotherapy, or their combination [8]. Although some pharmaceutical methods have significant advantages, psychotherapy such as Acceptance and Commitment Therapy (ACT) [9] can clinically and significantly improve the majority of patients [9]. In ACT, patients are encouraged to change their relationships to emotions and cognitions by practicing acceptance, mindfulness, and value-based performance [10]. ACT relies on six core processes (acceptance, contacting with the present moment, self as context, cognitive defusion, committed action, and values) to improve psychological flexibility [11]. ACT has a unique quality in treatment of chronic diseases due to focusing not only on the alleviation of pain but also on the increase of pain acceptance [12]. McCracken & Zhao-O’Brien defined chronic pain acceptance as the willingness to perform an activity without attempting to control or ameliorate pain [13], which is associated with less pain and discomfort and lower levels of depression, anxiety, and disabilities. It can also predict some levels of daily activities. In other words, pain acceptance, willingness to experience pain, and activity engagement are the elements of ACT [12]. 
Different treatment approaches have common factors that play a more effective role than the obvious theoretical and technical differences in creating a sense of improvement in patients. Hope and expectation from the treatment are one of these effective factors [
14]. The role of hope in having proper performance has been highly mentioned in psychotherapy literature. The positive effect of hope on mental and physical health is considered as a key factor in psychotherapy [15]. Hope and expectation from treatment as motivating factors can stabilize behavior and have a biological effect like the placebo method [161718]. Considering the effect of ACT on the treatment of psychological disorders such as depression, chronic fatigue, and sleep in the clinical population [19], and given that less attention in studies has been paid to the influential factors of ACT such as patients’ hope and expectations and the durability of treatment effect, more studies are required to definitely talk about the application of ACT. In this regard and given the higher prevalence of FMS among women and the psychological disorders associated with FMS which can interrupt the physical treatment and decrease healthy social and family functioning in patients, the present study aims to evaluate the effect of ACT on depression, chronic fatigue, and pain intensity in FMS patients considering their expectations and using a three-month follow-up. 
Materials and Methods
This was a quasi-experimental research with a pretest-posttest design, a control group, expectancy effect, and a three-month follow-up. The statistical population included all FMS patients who were referred to the rheumatology clinic of Bu Ali Hospital, Tehran during December-February, 2019, selected by convenience sampling. Estimation of sample size based on comparison of two groups using G * Power v 3.1 software and using large effect size with a value of 0.82 and the error rate of the first type is 0.05 and also the power is 0.80 and in Each group received 20 samples and 40 samples in total. The selected subjects were randomly divided into two groups of test and control (expectancy list). Inclusion criteria were women between the ages of 18 and 60 with fibromyalgia who were diagnosed by a specialist based on the 2010 American College of Rheumatology clinical criteria, having a high school education, the presence of pain based on the McGill Pain Scale, and the fact that subjects with this research, they should not participate in any training course on psychological services and should not be under special medical treatment. Exclusion criteria also include not attending intervention sessions for more than one session, unwillingness to continue attending intervention sessions, presence of bone and metabolic disease, diabetes, liver disease, chronic kidney failure, cancer, heart disease and psychiatric disorders such as major depression. By reviewing the client file in the clinic, which had previously been screened by a physician, and undergoing psychological treatment at the same time as the present study. Considering that during the sampling period, no sample was found in the age range of 18 to 30 years for referral to the clinic, so we were satisfied with the selection of samples in the age range of 31 to 60 years. For implementation, after approving the proposal and obtaining the code of ethics, the data were collected at IR.iau.k.iec.1398,066 by referring to the clinic according to the said cases. Afterwards, the subjects were asked to fill demographic characteristics questionnaire, Beck Depression Inventory, McGill Pain Questionnaire, and Krupp Fatigue Severity Scale in the form of a pretest.
However, the protocol was revised for FMS patients and included eight two-hour group therapy sessions. Every week, one session was held for the test group to present the content and principles shown in Table 1 while the control group was on the waiting list.

A posttest was carried out in both groups at the end of the sessions, and the subjects were followed up for three months after that. In order to adhere to ethical considerations, the participants in the control group received ACT training immediately after the posttest. Moreover, data analysis was performed in SPSS software v. 22 using descriptive statistics (frequency, mean and standard deviation), and one-way analysis of covariance. 
The BDI has 21 items rated on a 4-point scale from 0 (not at all) to 3 (severely). The total score ranges 0-63, where a score of 0-13 indicates the minimum level of depression, and scores of 14-19, 20-28, and 29-63 show mild, moderate and severe depression, respectively. Internal consistency of the BDI is 0.92 for outpatients and 0.93 for non-clinical samples, and has a test-retest reliability of 0.93 in a one-week interval [
21]. For its Persian version, there is a correlation between the scores of this questionnaire and the brief symptom inventory (depression scale) (r=0.87). Moreover, its factor analysis identified three factors of somatic-performance, cognitive-affective, and pessimistic- feeling worthless. Furthermore, the reliability of the entire questionnaire was reported α=0.91 [22]. The FSS is a 9-item tool developed by Krupp et al. to assess the severity of fatigue. The items are scored on a 7-point Likert scale from 1 (totally disagree) to 7 (totally agree), where higher scores indicate higher severity of fatigue [23]. reported the reliability of its Persian version as α=0.96 [24]. The MPQ is used to assess the qualitative and quantitative aspects of pain and has 20 sets of words to describe the pain. The scoring is based on the spatial properties of words, meaning that the first words of each set are received one point. Therefore, the selected words not only show the quality of pain, but also their severity. The sum of scores obtained from the selected words in different sets is called the Pain-Rating Index (PRI). Dwoekin et al. reported the Cronbach’s alpha of the instrument as 0.95. For its Persian version, the reliability was reported α=0.85. In a research by Rezvani et al., the concurrent validity of Persian MPQ compared to the Visual Pain Scale was estimated 0.86 [25].
The treatment protocol was derived from Wells and Sorrell’s study on chronic pain [
20] presented to the intervention group after modification for FMS patients which included 8 two-hour group therapy sessions, one session per week (Table 1), while the control group was put on the waiting list.
ACT is a unique approach based on the relational framework theory. ACT combines behavior change techniques, acceptance and mindfulness, and focus on psychoeducation, problem-solving, cognitive defusion, dealing with other strategies, and experiential avoidance. Mindfulness and acceptance skills facilitate the necessary behavioral change for patients to experience a purposeful and vibrant life [
Participants were 40 women with FMS in two groups of intervention (n=20) and control (n=20). In the intervention group, 11% aged 31-36 years, 24% aged 37-42 years, 29% aged 43-48 years, 18% aged 49-54 years, and 18% aged 55-60 years. In the control group, 6% aged 31-36 years, 12% aged 42-37 years, 29% aged 43-48 years, 24% aged 49-54 years, and 29% aged 55-60 years. Furthermore, in the intervention group, 6% had high school education, 40% had diploma, 24% had associate degree, 18% had bachelor’s degree, and 12% had master’s degree. In the control group, 12% had high school education, 46% had diploma, 18% had associate degree, 18% had bachelor’s degree, and 6% had master’s degree. Moreover, in the intervention group, 53% were housewives, 29% were working in government-owned companies, and 18% were working in non-governmental companies, while in the control group 41% were housewives, 35% were working in government-owned companies (35%), and 24% were in non-governmental companies (24%).
Descriptive indexes of the variables of depression, pain intensity, and fatigue in three pretest, posttest, and follow-up modes are presented in (Table 2).

Given the establishment of the assumptions of the covariance test, we used the summary of the result of the analysis of variance/covariance. In addition, the Shapiro-Wilk test was applied to assess the normality of the scores of depression, pain intensity, and fatigue. The normality of the two groups in terms of the scores of depression, pain intensity, and chronic fatigue at two pretest and posttest stages showed the normal distribution of the scores (P>0.05). In addition, the data normality assumptions were met. Furthermore, the results of the Box’s M test were indicative of the similarity of the covariance matrix in the two groups in terms of these variables. Levene’s test was applied to evaluate the equality of the variance of the two groups, and the results were indicative of no significant difference of variance in the two groups. Moreover, the F statistic test demonstrated the interaction of the independent and covariate variables in the data of both research variables, which was not significant in this index (P>0.05). Therefore, the assumption of inequality of regression slope was not rejected. According to the results presented in (Table 3) and the assumptions of repeated measures ANOVA test such as shapiro-Wilk tests,Levin's test and Mauchly's sphericity test demonstrate they are met in this survey.

According to Table 4, there was a significant difference between the two groups regarding the scores of depression, pain intensity, and fatigue in the posttest stage by controlling the impact of the pretest (P<0.05).

As observed in Table 5, time had a significant effect on the variable of depression (F=121.593, P<0.001).

Therefore, a significant difference was found between the mean scores of depression in the pre-test, post-test, and follow-up, regardless of the test group. Moreover, the interaction between time and the group was significant in the depression index (P<0.001), which showed a difference in the mean score of depression in various times with regard to the variable categories of groups. In addition, the impact of the group on the mean score of pain intensity was not significant regardless of time (F=0.039, P=0.844). On the other hand, time had a significant effect on the variable of pain intensity (F=84.58, P<0.001). As such, there was a significant difference between mean scores of depression in the pretest, posttest, and follow-up regardless of the test group. Furthermore, there was a significant interaction between time and group regarding depression (P<0.001), which demonstrated that different mean scores of depression were different at various times depending on the variable categories of the group. On the other hand, the group had an insignificant effect on the mean score of depression regardless of time (F=0.680, P=0.416). In addition, time had a significant effect on the variable of fatigue (F=75.553, P<0.001). Accordingly, there was a significant difference in the mean scores of fatigue in the pretest, posttest, and follow-up stages regardless of the test group. Moreover, time and group had significant interaction in depression (P<0.001), which showed the difference between the mean scores of depression at different times according to the variable categories of the group. On the other hand, the group had an insignificant effect on depression score regardless of time (F=0.034, P=0.564)
The purpose of the present study was to evaluate the effectiveness of ACT in reducing depression, pain intensity, and fatigue in patients with FMS and assess the impact of treatment considering other factors, including patients’ hope and expectations using a 3-month follow-up period. According to the results, the effect of ACT on the two groups was significant. In other words, the effects were constant not only at baseline but also three months after. In this regard, our findings are consistent with the results of Javadi et al. [
19], Hagh Ghadam et al. [27], Taheri et al. [28], Golestanifar & Dasht Bozorgi [29], Zahedi et al. [30], Hamidah [31], Lin et al. [32], and Feliu-Soler et al. [33]. These studies had clearly shown the impact of ACT on patients with various diseases. 
According to Hayes, many therapies believe that negative emotions and thoughts, (e.g. anxiety, depression, obsessions, or delusions) are problems that should be eliminated. In ACT, these negative and unpleasant emotions are not considered as the primary goals of treatment, and efforts to avoid these emotions are considered inefficient. For example, trying to escape from emotional pain only intensifies it, making the person more involved and turning the pain into a traumatic experience [
34]. Furthermore, one of the important principles in ACT is its emphasis on acceptance. Through various metaphors and training, patients learn the difference between acceptance and tolerance, and train acceptance skills in a variety of difficult internal events. They learn to experience intense feelings or pay attention to intense physical emotions without any harm [35]. Therefore, it can be argued that the goal of ACT is not to change our negative thoughts and emotions but is to take the necessary measures to help us accept and be aware of them [36]. Therefore, the main goal is to increase patients’ willingness towards psychological flexibility, where a person can be fully present here and at the present moment without judgment, evaluation, and rejection of experiences, thoughts, feelings, emotions, and physical symptoms. 
In the present study, the acceptance-related techniques (such as the quicksand metaphor, solving depression, somatization, and sitting with emotions to decrease pain and increase flexibility) could reduce depression, chronic fatigue, and pain intensity in patients with FMS. The commitment-related techniques (such as value identification, tombstone exercise, and praising others), patients were helped to identify the valuable aspects of their life, recognize obstacles in their path and, consequently, increase self-satisfaction and life satisfaction which led to their reduced depression [
30]. There is promising support for the cost-effectiveness of ACT; however, the current evidence is still insufficient to confirm the cost-effectiveness of this method [33]. 
In our study, acceptance and commitment to hope and expectation during treatment had a significant impact on depression, pain intensity, and fatigue in FMS patients. Various studies have confirmed the effectiveness of ACT in Iran and other countries [
272829, 30, 37383940]. Lotfi Kashani et al. discussed the role of hope as a common factor in the effectiveness of different psychotherapy approaches and reported the significant contribution of hope and expectation of treatment in the feeling of improvement in patients, which is not in line with our findings [41]. Moreover, studies have shown that hope causes positive changes in the central nervous system [42], promotes health [43], reduces anxiety symptoms as a psychological mediator [44], and helps patients have lower depression, anxiety, and pain. Therefore, by having such perspective on hope and expectation about treatment, it can be used to facilitate the treatment process of patients. However, according to our findings, the concept of hope and expectation is not the same as that of ACT, and are ranked lower in terms of contribution and impact on the treatment process. 
ACT has a significant impact on depression, pain intensity, and chronic fatigue in FMS patients. Our findings could be employed by health specialists and therapists and help take measures to improve the mental health level and reduce symptoms in FMS patients, which can lead to increased life expectancy, adaptation to the disease conditions, and better interpersonal relationships.
One of the major drawbacks of the present study was including only female patients and lack of male patients. Moreover, this study was conducted in one city (Tehran). To generalize the results, pilot studies should be carried out in other cities so that different people with chronic diseases can benefit from these services.

Ethical Considerations
Compliance with ethical guidelines

All ethical procedures were considered in this study. An ethical approval was obtained from the Research Ethics Committee of Islamic Azad University, Karaj Branch (ID:IR.IAU.K.IEC.1398.066). Informed consent was obtained from all participants.

This study received no financial support from any organization.

Authors' contributions
All authors had contributed equally to preparing this work.

Conflicts of interest
According to the authors, there was no conflict of interest.

All the people who participated in the present study are appreciated.

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Type of Study: Original | Subject: Mental Health
Received: 2021/04/3 | Accepted: 2021/06/30 | Published: 2022/01/1

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