The Nature of Fatigue in Chronic Fatigue Syndrome.

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research-article2015

QHRXXX10.1177/1049732315573954Qualitative Health ResearchOlson et al.

Article

The Nature of Fatigue in Chronic Fatigue Syndrome

Qualitative Health Research 1–13 © The Author(s) 2015 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1049732315573954 qhr.sagepub.com

Karin Olson1, Oksana Zimka1, and Eleanor Stein2

Abstract In this article, we report the findings of our study on the nature of fatigue in patients diagnosed with chronic fatigue syndrome. Using ethnoscience as a design, we conducted a series of unstructured interviews and card sorts to learn more about how people with chronic fatigue syndrome describe fatigue. Participants (N = 14) described three distinct domains: tiredness, fatigue, and exhaustion. Most participants experienced tiredness prior to diagnosis, fatigue during daily life, and exhaustion after overexertion. We also discuss participants’ ability to adapt to a variety of stressors and prevent shifts to exhaustion, and relate our findings to stress theory and other current research. Primary strategies that promoted adaptation to stressors included pacing and extended rest periods. These findings can aid health care professionals in detecting impending shifts between tiredness, fatigue, and exhaustion and in improving adaptive strategies, thereby improving quality of life. Keywords coping and adaptation; ethnoscience; fatigue / exhaustion; illness and disease, experiences; stress / distress; theory development Fatigue is ubiquitous. In daily life it is commonly understood to be associated with physical labor, exercise, psychological strain, or lack of sleep as well as diseases such as cancer, depression, and chronic fatigue syndrome (CFS). In the context of disease, fatigue appears to develop when least expected or be noticeably absent despite advanced disease (Olson et al., 2002). The lack of research comparing fatigue in ill and non-ill individuals has made it difficult to identify the attributes of fatigue that are common across populations as well as those attributes that are unique in a given population. Knowledge of these variations could be used to guide interventions. To address this gap, we conducted qualitative studies in three ill and two non-ill populations: persons living with cancer, depression, or CFS; shift workers; and recreational runners, respectively (Olson, 2007; Olson, Krawchuk, & Quddusi, 2007; Porr, Olson, & Hegadoren, 2010). Our main finding was the identification of two additional concepts, tiredness and exhaustion, which were closely related to fatigue, and a broader concept called adaptive capacity, which linked the concepts of tiredness, fatigue, and exhaustion in a manner consistent with stress theory (Selye, 1952). Drawing on this work, we proposed an initial model of fatigue (Olson et al., 2008), which we are in the process of testing, and have developed an instrument to measure adaptive capacity (Olson et al., 2011). In this article, we reported the

detailed analysis of our study of fatigue in individuals with CFS.

Literature Review Researchers at the Centers for Disease Control and Prevention (CDC, 2012) have described CFS as a devastating, complex disorder characterized by “severe chronic fatigue for 6 or more consecutive months . . . not due to ongoing exertion or other medical conditions associated with fatigue.” This fatigue must significantly interfere with daily activities and work and be accompanied by at least four of eight additional symptoms (CDC, 2012). The most commonly used case definitions of CFS are summarized in Table 1. Prevalence estimates vary widely depending on the definition used and whether the study involved individuals in primary care (higher prevalence) or community settings (lower prevalence). One well-conducted study estimated CFS prevalence at 422 per 1

University of Alberta, Edmonton, Alberta, Canada University of Calgary, Calgary, Alberta, Canada

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Corresponding Author: Karin Olson, University of Alberta Faculty of Nursing, Level 3, Edmonton Clinic Health Academy, 11405 87 Avenue, Edmonton, Alberta, Canada T6G 1C9 Email: [email protected]

Downloaded from qhr.sagepub.com at Kyungpook National University on August 12, 2015

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Qualitative Health Research

Table 1. Working Case Definitions for Chronic Fatigue Syndrome. Criterion Minimum duration

Fukuda 1994a 6 months

Oxford 1991b

Canadian Consensus 2003c

CFS: 6 months, symptoms 6 months present more than 50% of the time PIFS: Syndrome present 6 months at least 6 months after onset of infection Definite and persistent Substantial, at a minimum change from a previous meets criteria on two level of functioning of three designated subscales

Functional impairment Substantial

Cognitive or neuropsychiatric symptoms

Might be present

Not specified

Other symptoms

Four required

Autonomic, neuroendocrine, and immune manifestations

None required

Fatigue that is severe, Fatigue, postexertional disabling, and affects malaise, sleep physical and mental dysfunction, and pain/ functioning discomfort all required Possible myalgia or mood and sleep disturbances Not specified One or more symptom in two of the three categories required

Onset

New required

Medical exclusions

Clinically important

Psychiatric exclusions

Melancholic depression, substance abuse, bipolar disorder, psychosis, and eating disorder

Two or more required

CFS: Definite onset, not Distinct onset but might lifelong be gradual PIFS: In addition to above, definite evidence of infection at onset or presentation Established medical Extensive list of active conditions known to disease causes produce chronic fatigue Schizophrenia, manic Primary psychiatric depressive illness, disorders and substance substance abuse, eating abuse disorder, and proven organic brain disease

Note. CFS = chronic fatigue syndrome; PIFS = postinfectious fatigue syndrome. a Fukuda et al. (1994); Christley, Duffy, and Martin (2012). b Sharpe et al. (1991). c Carruthers et al. (2003); Jason et al. (2010). d Carruthers et al. (2011).


International Consensus 2011d Not specified At least a 50% reduction in preillness activity level (mild) Can be moderate (mostly housebound), severe (mostly bedridden), or very severe (completely bedridden and needing help with basic functions) At least one symptom from three of four neurological impairment categories Dyslexia on exertion, difficulty focusing eyes/reading, slow information processing, pain might seem erratic and migrate quicklye Must meet criteria for postexertional neuroimmune exhaustione Headaches/migraines are common Immune, gastrointestinal, and genitourinary impairments: at least one symptom from three of the five categories Energy production/ transportation impairments: at least one symptom Not specified

Physical examination and lab/biomarker testing as indicated by patient history Primary psychiatric disorders, somatoform disorder, and substance abuse “Primary” school phobiae

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Olson et al. 100,000 community-dwelling adults (Jason, Benton, Torres-Harding, & Muldowney, 1999). Significant functional recovery occurs in fewer than 10% of adults diagnosed with CFS. Higher-than-average rates of CFS have been reported in people recovering from viral infections (White et al., 2001), women (Jason, Porter, Hunnell, Rademaker, & Richman, 2011), ethnic minorities (Bhui et al., 2011; Dinos et al., 2009), and people of lower socioeconomic status (Jason et al., 1999). Elevated CFS rates were also evident in people who were depressed or anxious (Henningsen, Zimmermann, & Sattel, 2003), genetically predisposed (Albright, Light, Light, Bateman, & Cannon-Albright, 2011), physically inactive (Bhui et al., 2011), or exposed to environmental toxins (Devanur & Kerr, 2006). Recent evidence has explored the physiologic etiology of CFS. Researchers have identified several mechanisms, including mitochondrial dysfunction (Booth, Myhill, & McLaren-Howard, 2012), chronic inflammation (Maes, Twisk, Kubera, & Ringel, 2012), neuroendocrine dysfunction (Silverman, Heim, Nater, Marques, & Sternberg, 2010), and immune abnormalities (Bansal, Bradley, Bishop, Kiani-Alikhan, & Ford, 2012). In response to the growing body of pathophysiological research on CFS, a panel of researchers, clinicians, teaching faculty, and independent patient advocates from 13 countries developed international consensus criteria (Carruthers et al., 2011). Carruthers et al. devised diagnostic criteria based primarily on physiological dysfunction, including dysregulation of the central nervous and immune systems, dysfunction of cellular energy metabolism and ion transport, and cardiovascular abnormalities. However, this definition has not yet been validated and thus is not commonly used in practice. These researchers argued that a 6-month waiting period should not be a requirement for diagnosis because patients with severe symptoms suffer needlessly for an extended time frame. Instead, they suggested that a diagnosis should be made after appropriate clinical investigation, with no restrictions based on symptom duration. Prior to the recently published work on the pathophysiology of CFS, researchers attributed the persistence of fatigue in CFS to a variety of determinants. Currently, the most strongly predictive factor for prolonged illness, particularly postinfection, is illness severity (Hickie et al., 2006). Other factors include premorbid lifestyle (Van Houdenhove, Neerinckx, Onghena, Lysens, & Vertommen, 2001), cognitive characteristics (Petrie, Moss-Morris, & Weinman, 1995), physical activity, and social support (Bhui et al., 2011). Definitive information on causes and treatments of CFS is still lacking, leading one CFS patient to state that the hopeful thing about the disease is that “You don’t die from chronic fatigue syndrome. And the bad news is, well, you don’t die from

chronic fatigue” (Schoofs, Bambini, Ronning, Bielak, & Woehl, 2004, p. 373). Unlike many other fatigue-related conditions, the multifactorial and diagnostically elusive nature of CFS means that individuals must endure a lengthy and frustrating sequence of testing procedures before a diagnosis is made. This experience is compounded by disease-related pain and disability, and mental anguish when family and trusted health care professionals doubt their illness. Dismissive physician attitudes, in particular, significantly affect the CFS illness experience and can result in a damaged therapeutic relationship, feelings of abandonment, undue stress, delay in diagnosis and treatment, delay in access to social services and support, and inadequate research funding (de Carvalho Leite et al., 2011; Stein, 2001). The purpose of this study was to learn more about the nature and meaning of fatigue to people diagnosed with chronic fatigue syndrome. The primary research question in this study was as follows: Research Question 1: How do individuals with CFS describe fatigue?

Method Design Language is the primary vehicle for sharing cultural knowledge (Evaneshko & Kay 1982; Leininger, 1985; Spradley, 1979). In this study, we therefore used ethnoscience, a qualitative design rooted in anthropology, because it provided a systematic approach for studying how individuals use language to classify and interpret cultural knowledge and the meaning attributed to this knowledge. Researchers using ethnoscience begin with broad, open-ended questions designed to elicit the primary distinguishing attributes (segregates) of a concept or area of interest (domain). They then ask specific questions to elicit smaller descriptive units, called subsegregates, which show the relationships among the segregates. The researcher then conducts a componential analysis to further refine the relationships within the domain (Leininger, 1985). The culture of interest in this study was individuals with CFS. We began by focusing on the attributes of fatigue but added an exploration of tiredness and exhaustion early in the study because participants indicated that these two domains were relevant to the meaning of fatigue.

Sample For the results of a qualitative study to be valid, the sample must comprise individuals who have had firsthand experience with the topic being studied, in this case CFS,


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and can describe their experience in an articulate manner (Morse, Barrett, Mayan, Olson, & Spiers, 2002). For this reason, we selected participants who had been diagnosed with CFS by a physician using the definition published by Fukuda and colleagues (1994). All participants were at least 18 years of age, able to speak and read English, resided in a large Western Canadian city, and had sufficient energy to participate in a 30-minute recruitment interview and at least two to three interviews lasting up to 90 minutes each.

Data Collection and Analysis Following ethical clearance by the Health Research Ethics Committee at the University of Alberta and permission from a local CFS support group to access their members, we presented information about the study at a support group meeting. Some individuals passed information about the study on to other individuals diagnosed with CFS who had not attended the meeting, including individuals who were not part of the CFS support group. A member of the research team met with all individuals interested in the study, answered their questions, obtained written consent from those interested in participating, and scheduled an appointment to begin data collection. The group of individuals with CFS attending the support group in the city where data were collected is small, so our primary concern was related to anonymity. For this reason, we removed all personal identifying information from the transcripts, including the city where the data were collected, and assigned a study identification number to participants. We recruited participants until no new information was obtained. We interviewed participants two or three times each and audiotaped and transcribed all interviews to facilitate analysis. We began the first interview with an opening statement such as, please tell me what a typical day is like for you. When participants made comments pertaining to fatigue, we asked questions that explored the boundaries of this term (e.g., How is the kind of fatigue you have now similar to or different from the kind of fatigue you had before you were diagnosed with CFS?). Participants often used the terms “tiredness” and “exhaustion” to talk about their fatigue, so we expanded the study to focus on all three domains. We reviewed transcripts while listening to the interview recordings to ensure that the transcripts were accurate. Following review and correction of transcripts if necessary, we identified words that either fit the conceptual definitions of tiredness, fatigue, and exhaustion created during the reconceptualization phase of our work (Olson & Morse, 2005) or were new words used to describe tiredness, fatigue, and exhaustion and placed these words on small cards for use during the cardsorting exercise in the second interview (Spradley, 1979).

We conducted second interview with all participants. This interview began with an invitation to sort the cards into as many piles as desired. We asked participants to think aloud as they sorted the cards into piles, to name each pile, and to talk about how the piles were similar to or different from each other. Next, we asked participants to sort the cards into only three piles, again thinking aloud as they sorted the cards and naming each pile. Last, we asked participants to sort the cards into two piles, label the piles, and talk about how they were similar or different. In each case, we noted on the back of the card the name of the pile to which the card was assigned. This interview was also recorded and transcribed to facilitate analysis. Throughout this process, participants were told they could discard cards that did not apply to them or create cards for words that were not included. Thus, at the conclusion of the second interview, the data for each participant included the cards they sorted into piles (including any added cards), each with three labels on the back, one corresponding to each card sort, and the cards that were discarded. Following each second interview, we constructed a matrix with the names of the piles for the first card sort as the column headings and the names of the piles for the second sort as the row headings. We placed each card into the square in the matrix that corresponded to the way the participant had categorized it during the first two card sorts. We drew the results of the third sort on the matrix by hand. By overlapping the card sorts in this way, we were able to identify patterns in the words used. We then tentatively identified the meanings of these words by considering them alongside the descriptions of the piles provided during the card-sorting process and constructed a table using this information. We constructed three tables at the end of every second interview, one each for tiredness, fatigue, and exhaustion. As the study progressed, we compared the tables we constructed following the second interviews of each participant and finally constructed a taxonomy based on these data showing the segregates and subsegregates for each domain (Table 2). We conducted third interviews with two particularly articulate participants to verify the analysis. We conducted the componential analysis by reviewing the final taxonomy and asking a series of yes and no questions of the data, such as, “Did all participants describe reduced activities of daily living (ADLs) as part of fatigue?” and “Did all participants describe the loss of comprehension as part of exhaustion?” This analysis was possible because participants had described experiences from all three domains (tiredness, fatigue, and exhaustion). The objective of the componential analysis was to identify the conceptual boundaries between the domains of tiredness, fatigue, and exhaustion, and particularly to explore whether the relationships between these three


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Olson et al. Table 2. Segregates and Subsegregates of Tiredness, Fatigue, and Exhaustion as Experienced by Patients Diagnosed With CFS. Segregates Domain

Affective

Tiredness

Tense “In control”

Fatigue

Impatient Scared Anxious Not happy Overwhelmed Unable to deal with negative emotions Panicked Devastated “Choose to maintain control”

Exhaustion

Too sick to “feel” “Out of control”

Muscular Weakness Stiffness that does not go away Reduced activities of daily living Muscle spasms Legs like rubber bands Reduced stamina Cannot make limbs move

Physical collapse Cannot get out of bed So tired I fall over “Like being in intensive care”

Somatic Heaviness Sleep disturbance Wake up tired “Like too much to drink” Nausea, vomiting Diarrhea Sensory alterations Metal taste Burning eyes Cannot tolerate noises or pressure Weight changes Echo in head No energy Wiped out Drained

Cognitive

Social

Short attention span Minor brain fog Cannot focus Memory is blocked Cannot identify Cannot write Cannot name Cannot identify Major brain fog Confused

Try to keep going

Memory is gone Cannot comprehend Logic gone

(Continues as above)

Altered relationships Too tired to participate Others withdraw

Note. Subsegregates are shown directly below segregates. CFS = chronic fatigue syndrome.

domains were consistent with the results from our studies of individuals with cancer and depression.

Rigor We addressed rigor in this study by adhering to the verification strategies proposed by Morse et al. (2002). We explicitly selected our design given its fit with the purpose of our study and our research question. We carefully recruited individuals to ensure they had extensive firsthand experience with CFS and continued to recruit participants until no new information was obtained. We used this standard indicator of data saturation as evidence of data adequacy. We analyzed and collected data simultaneously and discussed the findings in relation to other relevant research. In addition to the issues related to sampling outlined above, we safeguarded the validity and reliability of the findings by modifying the questions asked of participants as the study progressed to ensure that our findings reflected emerging concepts central to the experiences of tiredness, fatigue, and exhaustion in this population. We used field notes and transcripts to support the analysis and kept notes of discussions and decisions made in research team meetings.

Results We recruited 15 individuals. One individual who originally volunteered decided to withdraw before the first

interview. Thus, 13 women and 1 man participated in the study. Ages ranged from 37 to 68. The majority of participants were single (n = 6) or married (n = 5). One participant was in a common law relationship, and one was separated. The taxonomy in Table 2 illustrates the segregates and subsegregates of tiredness, fatigue, and exhaustion as experienced by participants diagnosed with CFS. We identified five segregates that were common to all participants: affective, muscular, somatic, cognitive, and social changes. We identified differences among tiredness, fatigue, and exhaustion by focusing on the changes in attributes in our five segregates. The participants described tiredness as something they experienced prior to being diagnosed, while in remission, or once in a while on “good days.” Most participants described leading active lifestyles prior to their CFS diagnosis and continuing to “push” through tiredness only to find themselves increasingly unable to recover energy. Participants experienced symptoms of the fatigue domain on a daily basis and symptoms of the exhaustion domain on overexertion. Several reported periods of exhaustion during which they were unable to regenerate any energy for prolonged periods, even with constant bed rest. One participant described this period as lasting a year and being so severe that the participant’s spouse thought “that I would not make it through.” Most participants discussed structuring their day and activities to prevent exhaustion. They noted that, to a degree, they could predict circumstances that would push them into exhaustion, further demonstrating


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the distinction between the fatigue and exhaustion domains. However, although participants could foresee circumstances to an extent, exhaustion was sometimes completely unpredictable, further adding to the devastating effect CFS had on their lives.

Affective Changes Participants used the words “tense” and “in control” to describe tiredness. Experiencing fatigue, however, was characterized as feeling impatient, afraid, and frustrated because of being unable to function at full capacity, “like I used to.” The subsegregates of affect show the connections among the segregates of fatigue and exhaustion. For example, one participant described feeling frightened in the beginning stages of the illness because of the significant, unexplained change in physical and cognitive ability. Another feared failing to complete tasks or trying anything new. Some participants displayed depressive symptoms at the various stages of CFS. Several were mistakenly diagnosed with depression when symptoms of CFS began to emerge. Treatment for depression was not effective, and they were eventually diagnosed with CFS. Two participants were diagnosed with depression following the onset of CFS and had some relief of depressive symptoms with treatment, but the remainder of the CFS symptoms remained. All but one participant noted that they never experienced anhedonia (inability to experience pleasure) or suicidal ideation, which are common features of depression. Instead, many specifically said that decreased physical and cognitive functioning brought on depressive symptoms. Many participants also noted that they often felt that they were unable to manage negative emotions because of the energy required. One described choosing not to deal with emotional stress as a “defense mechanism” to prevent overexpenditure of energy. Despite the affective attributes of fatigue, participants reported that they still tried to maintain control of their daily lives. Following the onset of exhaustion, in contrast, participants said they felt a complete inability to predict or control any emotions. Several participants described this sensation as being too sick to “feel” anything.

Muscular Changes Participants described the subsegregates of tiredness as persistent muscle weakness and stiffness, and noted that these sensations occurred primarily prior to the CFS diagnosis or during remission. The fatigue domain was characterized by more significant muscular function deficits. Many participants had difficulty carrying out ADL, such as caring for their hair, fastening buttons, or tying shoes,

because of arm pain and weakness. One participant described “drop attacks,” a loss of control of the arms resulting in dropping objects. Another participant explained being unable to recuperate from normal activities: “After I cooked supper . . . my legs would just sort of be like rubber bands, like I experienced after I had done this marathon thirty-mile walk.” Many participants described frequently lacking stamina to walk for more than a few blocks or do any activity for an extended period. They “pushed” themselves to perform activities, exhaustion frequently resulted. Exhaustion was characterized by complete physical collapse and an inability to get out of bed. It usually came on suddenly and was “all-consuming,” “like being in intensive care.” One participant described being “somewhere between unconscious and semiconscious.”

Somatic Changes Within the tiredness domain, participants identified a sense of heaviness as the most frequent attribute. One participant said she felt as if she was “loaded with sandbags.” Sleep disturbances also characterized tiredness, and in the initial stages of the illness, the cumulative effect of sleep disturbance eventually resulted in fatigue. The morning was usually the most difficult time for participants. “I couldn’t sleep well, and I’d always wake up feeling worse, actually worse than when I went to bed.” Each participant described a variety of sensory alterations, such as blurry vision, burning eyes, ringing in ears, and crawling skin and a decreased tolerance of noise and pressure. Malaise and lethargy were also common. One participant described the associated sensation as being like having “too much to drink.” Diarrhea, nausea, and vomiting all manifested within the domain of fatigue and were sometimes referred to as “flu symptoms,” which “came and went.” Exhaustion was consistently described as feeling drained and wiped out: “It’s just completely unrelenting, it’s debilitating, it’s totally unpredictable exhaustion. You’re just totally wiped, and you have absolutely no energy.”

Cognitive Changes One of the most prevalent and debilitating attributes of CFS was alterations in cognitive functioning. Participants recalled a change in cognitive function that started in the tiredness domain and was characterized by a short attention span, minor brain fog, and trouble focusing. Participants typically noticed this change first when they began struggling in school or in their careers. As the illness progressed into the fatigue domain, participants described memory lapses, “huge blanks,” and “gaps in memory.” Many described frequently getting lost or leaving the


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Olson et al. house and being unable to remember where they were going or how to get home: “It just seems that you cannot remember where you put things; when you go there you’ve got something wrong, you carry the wrong thing to the wrong place; and you’re totally confused.” Some participants struggled with reading or writing because of difficulties with recognizing words, understanding sentences, recalling what was just read, and concentrating: “We call it brain fog when you’re doing something—like, if you’re reading a page in a book, and you read it four times, and you still don’t connect with it.” One participant described having difficulty recognizing people or things: “I don’t recognize I have to pee. I don’t recognize our dog, I don’t recognize our house . . . I just stare.” All participants mentioned that if they overexerted themselves, they would “pay for it,” referring to exhaustion, and would need to rest substantially more than usual for the next few days. When exhausted, participants described, they were unable to function mentally, having no memory and being unable to comprehend speech or make logical decisions.

Social Changes Social interaction was important to participants, and they used a variety of strategies to maintain it when possible. The times during which participants could engage socially were unpredictable and varied widely from one individual to the next, from minutes to a whole day. Many participants agreed that social withdrawal was a consequence of the cumulative effect of the other segregates, particularly decreasing physical and cognitive functioning. Participants reported that prior to their diagnosis with CFS, they felt more withdrawn from social circles because of their inability to maintain the same physical activity. Initially, in the tiredness phase, participants felt themselves working harder to maintain relationships and, despite symptoms, still tried to keep engaged in social circles. Many described slowly withdrawing from social circles as they entered the fatigue phase for the first time and maintaining relationships only with the closest family and friends because of the significant physical and mental effort required. Several participants described others in their social circles who withdrew from them: “You lose friends because, um, the friends you had sort of ran at the same pace as you did. Uh, your really good friends stay with you.” Participants said they felt too tired to participate in functions, lunches, or sometimes even phone calls and described how this altered their relationships. Several participants stated that doing too many activities with friends or doing simultaneous activities, such as eating and conversing with friends or family, “wipes you out.” Such

“oversocialization” would typically push participants into exhaustion, and they would have to rest for days or weeks.

Componential Analysis Throughout the interview and card-sorting process, most participants referred to having the ability to anticipate consequences of actions to some degree. These consequences were typically in the form of the necessary recovery period. For example, one participant stated, “If I were to walk half a mile, it would take me probably two weeks to recover from that exertion.” The ability to anticipate consequences of actions helped participants manage their disease. Consequently, most participants followed a highly structured routine to prevent overexpenditure of energy (overexertion). It also seemed, however, that energy requirements needed for a given activity varied. Days in which an activity required less energy than usual were called “good days,” whereas those that required more energy than usual were called “bad days.” Good days and bad days were often unpredictable. However, participants stated that they could sometimes sense impending overexertion and then used appropriate strategies to prevent exhaustion. In Figure 1, we illustrate the decision-influenced shifts between tiredness, fatigue, and exhaustion. Participants described perceiving the attributes of tiredness during the diagnosis phase and trying to use various adaptive strategies, such as activity pacing. Eventually, these adaptive strategies were no longer effective, and they noticed the attributes of fatigue. With time, participants began adapting and adjusted to fatigue, and the attributes of this domain defined a “new normal” for them. Periodically they slipped into exhaustion, usually because of overexertion. With rest, they were able to move back to fatigue but rarely moved to tiredness, as if they were trapped in a perpetual cycle of fatigue and exhaustion (represented by the dotted line within the model). Participants noted that they seldom experienced tiredness after the diagnosis. However, several described temporary periods of remission, during which they moved into the tiredness domain. Only one participant reported a full recovery. Several participants described the process of conserving and recovering energy to plan for special events in an attempt to prevent exhaustion. For example, one participant described resting for at least a month to prepare for a Christmas party. Participants described having no control over the body during exhaustion and typically having to rest for days, weeks, and sometimes months before they regained control and energy. Throughout the interviews, they frequently used terms such as “plug has been pulled,” “wiped out,” and “drained” to describe the lack of energy during exhaustion.


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Figure 1. CFS patients’ decision-influenced shifts between tiredness, fatigue, and exhaustion. Note. CFS = chronic fatigue syndrome.


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Olson et al.

Discussion Members of our research group developed the fatigue adaptation model from a series of five studies, including this one, of ill and non-ill participants experiencing fatigue (Olson et al., 2008). The findings we described in this article are consistent with those of our first two studies about tiredness, fatigue, and exhaustion in individuals with cancer (Olson et al., 2007) and depression (Porr et al., 2010). Comparing the results of this study to those from our studies of fatigue in individuals with cancer or depression, we found that some attributes of tiredness, fatigue, and exhaustion were experienced by individuals in all three study populations, but there were also some attributes that were unique to each study population. Comparison of these results to fatigue in our non-ill study populations (recreational runners and shift workers) will be discussed once those results are published. The attributes of tiredness varied the most among the three groups. Participants in the depression groups seemed to have a higher functional status than those in the cancer or CFS groups. However, members of all three groups described feelings of heaviness and weakness. The fatigue domain, on the other hand, displayed more consistent attributes among the three groups and included a sense of cognitive decline and the perception that one needed to push oneself to maintain activity. Attributes of the exhaustion domain were the most consistent among the three groups and can best be described by the word “cannot.” The depression group could not connect with anyone nor move. The cancer group could not move, use any energy, or have any emotions. The CFS group could not feel, get out of bed, comprehend, or use logic. We view this inability to do as an indicator of the loss of ability to control the body, as if the body has taken over control in a manner that is independent of participants’ intentions or desires. Some but not all participants in this study frequently experienced depressive symptoms throughout the course of their illness. Only two of those with symptoms were diagnosed with depression following diagnosis with CFS. Although some believe there is a significant overlap between CFS and depression, growing evidence, including our study’s findings, shows that CFS and depression are two distinct conditions (Griffith & Zarrouf, 2008; Hawk, Jason, & Torres-Harding, 2006). Our results suggest that depression diagnosed following diagnosis with CFS might be secondary to the debilitating nature of CFS. Another key finding in this study was the participants’ ability to adapt slowly to CFS symptoms and structure their lives to account for depleted energy reserves. We have named this ability adaptive capacity. Adaptation was a central theme in Selye’s (1952) stress theory and

general adaptation syndrome (GAS). Selye described the GAS as the systemic adaptive response to a non-specific stressor and noted that it occurs in three distinct stages: the alarm reaction, resistance, and exhaustion. The alarm reaction is the body’s initial response to prevent the onset of illness. After the attempt to return to homeostasis fails (because of increased intensity of stressor or prolonged exposure to the stressor), the body enters the resistance stage, in which adaptation takes place (Selye, 1952). In this study as well as our studies of individuals with cancer and depression (Olson et al., 2007; Porr et al., 2010), we found a period of increasing inability to recover energy, which was followed by participants’ use of a similar set of energy-sparing adaptive strategies. This, in turn, was followed by a slow recovery of energy and the ability to engage in a modified set of routine daily activities. This adaptive pattern is the primary cornerstone of our working hypothesis, that fatigue is a behavioral marker for the resistance stage of the GAS. Living beings possess a finite amount of adaptive energy over their life span, and an organism can use up this energy slowly over a relatively stress-free life or all at once on encountering an extreme stressor (Selye, 1952). This explanation is congruent with the unpredictable and rapid onset of exhaustion reported by our participants, who were unable to implement energy-sparing strategies. Over a prolonged illness such as CFS, the individual’s adaptive energy slowly dissipates, and he or she has less energy to adapt to even slight stressors. Similar to Selye’s (1952) exhaustion phase, which begins after adaptive energy is fully expended, all participants described exhaustion as having “no energy,” like being “drained” or “unplugged.” Selye also asserted that “a complete and prolonged rest period can again restore considerable resistance and adaptability to subsequent exposure” (p. 49). Our participants learned to pace daily activities with frequent rest periods in an effort to prevent exhaustion. They needed prolonged rest periods after exertion and even longer ones after overexertion. Another theory that relates to adaptive capacity is the model of conservation of resources (Hobfoll, 1989). Hobfoll described psychological stress in terms of the interaction between the environment and the cognitive domain. He asserted that people strived to gain, retain, and protect resources to offset the threat of potential or actual loss. Resources include objective ones such as a house or job; conditions such as health, marriage, tenure, and seniority; personal characteristics such as mastery, self-esteem, and optimism; and energies such as time, money, and knowledge (Hobfoll, 1989; Taylor, Jason, Shiraishi, Schoeny, & Keller, 2006). Hobfoll maintained that the foundational principle defining stress was the perceived or actual loss of resources, and that individuals inherently prioritize their value. Consequently, the loss of


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more valuable resources results in a higher level of stress. It follows that the loss of resources to a person with CFS might further diminish their adaptive capacity. This was evident in our participants’ descriptions of lost careers and educational opportunities, which depressive symptoms often followed. It is interesting to note that Hobfoll (1989) specifically discussed social support as being a resource only to the extent that it facilitates the preservation of valued resources, such as intimacy or self-esteem, because social relationships can also detract from the individual’s resources. This point is consistent with our findings. Social relationships were valuable only when participants had enough energy to participate. This often meant that the benefits of a social circle were outweighed by the drawbacks of expending excessive energy in maintaining such circles. Hobfoll’s work suggested that social support could increase adaptive capacity but only if it increased an individual’s access to a valuable resource.

Implications for Practice The results of this study suggest that fatigue management should be rooted in strategies that increase adaptive capacity. The primary strategy that participants used to improve adaptation was activity pacing. Consistent with widely accepted management strategies, pacing encourages patients to remain as active as possible within the limits set by their illness (Goudsmit, Nijs, Jason, & Wallman, 2012). Symptom-contingent pacing is rooted in concepts from the energy envelope theory, which suggests that effective management of CFS can be achieved through the alignment of energy expenditure with perceived energy levels (available energy) each day (Jason, 2008). Staying within the energy envelope refers to staying in a comfortable range of energy expenditure, preventing overexertion while maintaining optimal activity levels (Jason, Benton, Torres-Harding, & Muldowney, 2009). Jason et al. (2009) and Brown, Khorana, and Jason (2011) found that patients who stayed within their energy envelopes had improved physical functioning and decreased fatigue severity over time when compared with patients who functioned outside their energy envelopes. More specifically, CFS patients who began non-pharmacological treatment inside their energy envelope had a 37.6% improvement in physical functioning, and 16.0% improvement in fatigue severity compared with a 6.0%, and 2.7% improvement for those who started treatment outside their energy envelope (Brown et al., 2011). Individuals with CFS might find it helpful to record perceived energy every morning and continuously track fatigue levels after each activity. These results could be reviewed with a health care professional to help individuals identify

patterns in their energy that might permit activities of interest (Goudsmit et al., 2012). Such a structured approach to energy use might also help participants regain a sense of control over their daily lives. Cognitive behavioral therapy and graded exercise therapy are two other common non-pharmacological treatments used in CFS populations. Although not discussed by our participants, these therapies have showed positive results for some CFS patients (White et al., 2011). Our findings also indicate that it might be possible to prevent progression from fatigue to exhaustion by recognizing symptoms such as disturbed sleeping pattern and muscular “mushiness,” which indicate declining adaptation. Participants in our study said that strategies such as activity pacing, increased rest periods, stretching, massage, and division of large tasks into smaller, more manageable steps help to prevent progression into exhaustion. Taylor et al. (2006) successfully used the model of conservation of resources to develop a consumer-driven rehabilitation program for CFS patients. The program focused on assisting participants in recovering a net gain of resources to counteract the loss that accompanies a CFS diagnosis. Taylor et al. helped patients to regain control of their lives and used goal setting to motivate participant progress. In a series of illness management groups led by peer counselors, participants discussed a variety of topics, including activity pacing, cognitive coping skills, relaxation and meditation, employment and economic self-sufficiency, social relationships, medical approaches, and nutrition. Following these sessions, participants received seven additional months of individually tailored peer counseling focusing on self-advocacy training, goal attainment, and care coordination. Participants experienced moderate to large gains across all resources, including interpersonal, energy, material, work, well-being, and mastery (Taylor et al., 2006). Such resource-driven programs could substantially improve adaptive capacity in CFS patients by improving energy consumption and by helping individuals build ways to manage stress and gain required resources.

Limitations An assumption in anthropologic studies is that if participants are thoroughly enculturated and the analysis is conducted carefully, the descriptions generated will resonate with other individuals who are part of the same culture. Culture, however, is not monolithic. Rather, cultures are relational and comprise factors such as age, gender, ethnicity, race, socioeconomic status, geographical location, occupation, and personal and family situation (Kleinman, Eisenberg, & Good, 2006). The results of this study reflect the experience of those who participated, who were each part of many cultures. Additional research is


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Olson et al. needed to determine the extent to which the findings of our study resonate with others who were not part of the sample. Although we deliberately sought negative cases from among those within the CFS support group, it is possible that given the debilitating nature of CFS and the difficulties associated with obtaining a CFS diagnosis, the full range of the experience of CFS might not be included. Last, although little progress has been made over time in the treatment of CFS (Friedberg et al., 2012), the definition of CFS has evolved. Thus, the results of this study should be interpreted cautiously, and replications in other groups of individuals with CFS using the current case definition are strongly encouraged.

Concluding Remarks We used ethnoscience, a qualitative design, to explore how individuals diagnosed with CFS described fatigue. The results of our study indicated that fatigue in CFS was characterized by three separate domains—tiredness, fatigue, and exhaustion—with five segregates, including affective, muscular, somatic, cognitive, and social changes. A comparison of the subsegregates comprising each of these segregates showed how participants moved between tiredness, fatigue, and exhaustion. Consistent with Selye’s (1952) stress theory, our results provided additional support for our hypothesis that fatigue is a behavioral marker of entrance into the resistance stage of the GAS. Participants used a variety of adaptation strategies, including activity pacing, breaking activities into small and manageable tasks, and frequent rest periods to maintain their energy levels and prevent progression to exhaustion. Health care providers could utilize the findings of this study to help their patients understand the nature of CFS. In addition to research investigating biological markers and diagnostic testing for CFS, further research is needed to illuminate more fully the intersections between the psychosocial and physiological dimensions of CFS, and the optimal adaptation strategies that could prevent the transition from fatigue into exhaustion and help individuals with CFS manage their illness trajectory. Acknowledgment We thank Linda Niehaus, Janice Morse, and Betty Wills, who graciously assisted with data analysis.

Declaration of Conflicting Interests The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Small Faculty Grant from University of Alberta (no grant number received).

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Author Biographies Karin Olson, RN, PhD, CHPCN(C), is a professor at the Faculty of Nursing, University of Alberta, Edmonton, Alberta, Canada. Oksana Zimka, RN, BScN, is a master of nursing student at the University of Alberta, Edmonton, Alberta, Canada. Eleanor Stein, MD, FRCP(C), is a psychiatrist in private practice and a clinical lecturer in the Department of Psychiatry at the University of Calgary, Alberta, Canada.


The chronic fatigue syndrome.

The measurement of fatigue and chronic fatigue syndrome.

Chronic fatigue syndrome.

Chronic fatigue syndrome.

Chronic fatigue syndrome.

Chronic fatigue syndrome.

Chronic fatigue syndrome.

Chronic fatigue syndrome.

Chronic fatigue syndrome.

Chronic fatigue syndrome.

Redefining the chronic fatigue syndrome.

Predictors of Fatigue among Patients with Chronic Fatigue Syndrome.

Metabolome of chronic fatigue syndrome.

History of chronic fatigue syndrome.

Outcome in the chronic fatigue syndrome.

Outcome in the chronic fatigue syndrome.

Magnesium and chronic fatigue syndrome.

Supplements for Chronic Fatigue Syndrome?

Chronic fatigue syndrome and heterogeneity.

Myth of the chronic fatigue syndrome.

Taking chronic fatigue syndrome seriously.

Magnesium and chronic fatigue syndrome.

Chronic fatigue syndrome and depression.

Gender differences in chronic fatigue syndrome.