Objectives: Individuals with chronic fatigue and chronic fatigue syndrome (CFS) face debilitating symptoms as well as stressful life situations that may result from their condition. The goal of this study was to examine the coping strategies used by fatigue-discordant twin pairs. Methods: We utilized a co-twin design to assess how twin pairs discordant for chronic fatigue and CFS cope with stress. All twin pairs were administered the Revised Ways of Coping Checklist. Results: Overall, the pattern of coping strategies was similar for fatigued and non-fatigued twins. However, twins with chronic fatigue or CFS utilized more avoidance strategies than their non-fatigued counterparts; those with chronic fatigue also used more avoidance relative to problem-focused coping than their co-twins. Conclusions: These results suggest that while fatigue-discordant twins generally exhibit similar behavior patterns in order to cope with stress, there may be an association between fatigue and avoidance coping. Future research should focus on the role of avoidance and its relationship to fatiguing illnesses.
Fatigue is a common symptom in a variety of medical and psychological conditions. It is reported by 20–40% of patients seeking medical care [1], [2] and [3] and large community surveys indicate that up to half of the general population experiences fatigue [4], [5] and [6]. Unexplained persistent and debilitating fatigue is the hallmark of chronic fatigue syndrome (CFS). CFS is also characterized by sleep disturbances, depression, myalgia, neurocognitive difficulties, and other symptoms [7]. In clinical settings, CFS is most commonly diagnosed in educated, previously healthy, and productive women [8]. Because the etiology remains unknown, CFS is a diagnosis of exclusion [7]. Along with the debilitating symptoms, those with CFS often face many stressful life situations. For example, between 26% and 37% of patients with chronic fatigue or CFS were unemployed at their initial clinic visit [9]. In addition, patients with CFS have exhibited significantly worse functional status than the general population and depressed or medically ill patients [10] and [11].
Coping has been defined broadly as a person's cognitive and behavioral efforts in reducing or tolerating the demands of stressful events [12]. This view of coping also suggests that a person may cope by trying to actively manage a distressful situation and/or by attempting to reduce the emotional consequences of experiencing distress; depending on the demands of the situation, each coping strategy could be adaptive or dysfunctional. Individuals with chronic fatigue and CFS have been reported to employ a variety of coping strategies to deal with the debilitating consequences of fatigue. A study of 58 female patients with CFS reported using significantly more escape/avoidance strategies than 104 healthy controls [13]. In a retrospective study, CFS patients reported an increased use of escape/avoidance coping strategies after the onset of illness [14]. A more recent study found that primary care patients with chronic fatigue used an escape/avoidance coping style more frequently than age- and gender-matched patients without chronic fatigue [15].
Coping behaviors, in turn, can influence prognosis. While little is known about adaptive coping strategies in patients with CFS, the use of problem-focused coping has been associated with less depression [16] and better perceived health status [17] in other populations. In terms of maladaptive coping, however, avoidance strategies have been associated with greater fatigue, impairment, and other psychosocial disturbances in patients with CFS [18] and [19]. However, it is difficult to interpret these diverse findings because studies of coping and CFS suffer from numerous methodological shortcomings. These include poorly-defined methods for CFS sample selection, the absence of the consistent application of the Center for Disease Control and Prevention (CDC) criteria to diagnose CFS [7], and the use of inadequate or poorly described comparison groups.
The purpose of the present study was to conduct a co-twin control study of coping strategies in twin pairs discordant for chronic fatigue and CFS. The co-twin control design provides one of the most sensitive approaches for assessing the association of a specific condition, such as chronic fatigue, with subtle clinical, laboratory, or behavioral findings [20]. Since the non-ill twins serve as natural controls for their ill siblings, the co-twin design is especially helpful when the appropriate comparison groups are not well-defined. The twins included in this study were members of the newly constructed Chronic Fatigue Twin Registry.
