Journal of Community Psychology Volume 21. October 1993

Strategies in Identifying People with Chronic Fatigue Syndrome Leonard A. Jason, Genevieve Fitzgibbon, Stephanie L. Taylor,

Sharon Johnson, and Doreen Salina DePaul University

Chronic Fatigue Syndrome is an illness that is characterized by debilitating fatigue. Few non-treatment-based epidemiological studies have been con- ducted in assessing rates of this disorder. Problems in conducting non- community-based prevalence studies are discussed. In addition, pilot data showing strategies to reach people afflicted with CFS are presented. It is argued that community-based epidemiological efforts are needed in order to estimate prevalence rates o f this disorder.

Chronic Fatigue Syndrome (CFS) appears to be a heterogeneous disease syndrome that may be triggered by a variety of factors (Bakheit, Behan, Dinan, Gray, & O’Keane, 1992; Jason, 1993; Krupp, Mendelson, & Friedman, 1991; Shafran, 1991), and immune activation seems to be associated with many cases (Landay, Jessop, Lennette, & Levy, 1991; Ur, White, & Grossman, 1992). Attempts to specify diagnostic criteria for CFS have aroused considerable controversy (Armon & Kurland, 1991; Grufferman, 1991).

Holmes et al. (1988) developed the first working case definition of Chronic Fatigue Syndrome. Recently, Schluederberg et al. (1992) have modified this definition by broaden- ing the case definition. Several studies have estimated fatigue in the general population (David, Wessely & Pelosi, 1991; Lewis & Wessely, 1992), and there have been many uncontrolled reports of the prevalence of CFS (Murdoch, 1987; Shafran, 1991). Many of these studies are based on estimates from tertiary care centers, but these are sites where patients are more severely ill or are more highly motivated in seeking help (Gruffer- man, 1991).

The first epidemiological study was conducted by Lloyd, Hickie, Boughton, Spencer, and Wakefield (1 990). Physicians selected patients whose chronic fatigue had been present for at least 6 months, and where it was producing significant disability in the patient’s usual daily activities. With age-standardization, the CFS prevalence rate was 39.6 cases per 100,OOO at the end of the study. The authors asked 50 of the originally contacted 104 medical practitioners to review the notification procedure. Of the 43 who responded to this request, 32 had not notified cases, and 3 1 of them said that there were no cases in their practice. In other words, of these 50 sampled medical practitioners, only 11 notified cases. It is likely that many of the medical practitioners did not adequately survey their patients for CFS.

Under the direction of Walter Gunn (1991), an ongoing epidemiological study was begun at the Centers for Disease Control, and physicians in four cities referred their patients to the study. The prevalence rates of CFS in the four sites ranged from 1.8

The authors wish to thank Harriet Melrose, Lisa Schicht, Ruth Robins, and Nancy Flynn for their valuable

Requests for reprints should be sent to the first author, Department of Psychology, De Paul Unversity, feedback in developing our questionnaire.

Chicago, IL 60614.

339

340 JASON, FITZGIBBON, TAYLOR, JOHNSON, AND SALINA

to 6 per 100,OOO (Gary, Reyes, & Fukuda, 1992). As with the Lloyd et al. (1990) study, it is likely that many physicians are skeptical of the CFS diagnosis, thereby leading to an underepresentation of patients.

Price, North, Wessely, and Fraser (1992) provided prevalence estimates based on a random sample. Only one individual out of the entire sample would have been diagnosed with CFS (7.4 cases per l00,OOO). However, their definition represents a sig- nificant departure from Holmes et al.’s (1988) criteria. In addition, excluding patients with psychiatric illness is a procedure that underrepresents the extent of this illness.

The disparate rates mentioned above are possibly due to differences in criteria defini- tions and methods of case identification. The lowest rates were found in Price et al.3 (1992) study, which excluded all individuals with psychiatric diagnoses. Gunn’s (1991) and Lloyd et al.’s (1990) studies relied on physician referral for generating their initial samples. However, some physicians remain skeptical of the validity of the diagnosis of CFS, and this attitude probably precludes some CFS patients from entering the health care system. Finally, some patients do not have the economic resources to gain access to the health care system.

A recent study by Jason et al. (in press) attempted to avoid some of the above problems. In that study, nurses were directly surveyed through a mailed questionnaire, thus avoiding potential physician bias. The prevalence rates were 680 per 100,OOO for those nurses indicating they had CFS. These results need to be interpreted with caution because independent medical and psychiatric examinations were not conducted, and such data are currently being collected in a follow-up study. Of course, by focusing on nurses, who might constitute a high-risk population, it is possible that these data cannot be generalized to the entire population (Grufferman, 1991).

The present study explored some of the reasons for the discrepant prevalence rates reported above. By interviewing a sample of CFS-afflicted people, attempts were made to evaluate issues related to gaining access to a CFS population. In addition, potential confounds when deriving prevalence data from physician referrals were explored.

Method In the fall of 1992, the authors contacted ten CFS-afflicted individuals and requested

that they participate in a survey on methodological issues related to evaluating this disease. These individuals were known by the authors, and they represented a wide spec- trum of cases. Some of the CFS-afflicted individuals had been met during the course of conducting several CFS-related research projects during the past year. All participants were assured of the confidentiality of their responses. Once the 10-minute interviews were completed, we asked the participants if they knew of any other individuals with CFS who might be willing to be interviewed. Using this method, the authors generated a list of 46 individuals for this study. We specifically did not want to recruit people from a physician’s office, because we felt that method would preclude individuals who were not currently being treated by a physician. In addition, we did not want to recruit our participants from a CFS support group because we felt such a group might not be a representative sample of CFS-afflicted people.

Attempts were made to telephone all individuals, and careful records of these at- tempts were recorded. When we received an answering machine message, we did not leave any message. If someone other than our target person answered the telephone, and the CFS-afflicted person was not home, we indicated that we would call back but we did not leave a message. These efforts were initiated in order to insure that normal

STRATEGIES IDENTIFYING CFS 34 1

telephone answering behavior occurred during the course of our study. Once we reached these CFS-afflicted individuals, they were asked a variety of questions concerning their symptoms, medical or psychiatric diagnoses, and demographic variables. In addition, we asked questions related to how reseachers might gain access to interviewing them. No one refused to complete the survey.

Two of the 46 individuals had other diseases (i.e., multiple sclerosis, hepatitis C) that might have accounted for their symptoms, and they were eliminated from the sample. Two individuals had moved and left no forwarding number. As for efforts required to locate by telephone the remaining 42 individuals, 39 individuals were reached during the 8-week survey period within eight telephone attempts (93% success rate). For those three individuals we did not reach, on the eighth telephone call, we left a message on their answering machines requesting they call us back to complete our questionnaire on CFS. None of these individuals returned our call; thus, our final sample included 39 people. These 39 individuals all indicated that at least one physician had given them the diagnosis of CFS.

Results Table 1 presents the demographic characteristics and CFS symptoms of the final

sample (n = 39) that completed the telephone questionnaire. Twelve of the sixteen people on disability indicated that they received it for CFS. Our sample had an average of 9 minor symptoms (range 5-1 1). In addition, 92% had a greater than 50% reduction in activity level for 6 months or longer. Eighty-five percent of the sample fulfilled the con- servative Holmes et al. (1988) criteria for CFS (eight or more minor symptoms, greater than 50% reduction in activities for 6 months or more).

In terms of reaching our sample, it took an average of three times to contact them (range 1-8). Thirty-one percent were reached on the first call, 10% on the second call, 28% on the third call, 5% on the fourth call, 8% on the fifth call, 5% on the sixth call, and 13% on the eighth call. We reached an answering machine on at least one telephone call to 51% of our sample. Fifty-six percent of the respondents said that they screened their telephone calls. Seventy-seven percent said there were times during the day and evening that they did not answer the telephone, with the usual reason being feeling tired or sick.

Eighty-seven percent of the respondents said that they would have responded to the survey if it had been sent in the mail. When asked about their preferences for a mail versus a telephone survey, 64% mentioned a preference for a telephone survey, 10% for a mail survey, and 15% felt comfortable with both approaches. Four individuals (10%) responded that the combination of being sent a mail questionnaire to inspect, and then having this followed up with a telephone interview, was preferable. The most common reason given for a mail preference was that the respondent could fill it out when it was convenient. On the other hand, a number of the respondents indicated that a telephone survey was preferable because it would be more personal and less energy consuming.

If the respondents had been asked to participate in a study on CFS, which involved a physical exam and a psychiatric interview, 85% said they would agree to have it done in their homes and 72% said that they would agree to have it done in a hospital setting. Altogether, 89% indicated that they would have been willing to participate in such a study in their homes and/or at a hospital setting.

342 JASON, FITZGIBBON, TAYLOR, JOHNSON, AND SALINA

Table 1 Demographic and Symptom Variables for Sample

Variable Percentage

Gender Females Males

Age 18-29 30-39 40-49 50-56

Race Caucasian

Marital status Married Divorced Separated Never married

Work status On disability On disability/working part-time Not workingho disability Working part-time Working full-time

I year 2 years 3 years 4-5 years 6-10 years 11 or more years

Length of time sick with CFS

Reduction in activity level greater than 50% for 6 months or more Minor symptoms

Mild fever Sore throat Painful lymph nodes Unexplained generalized muscle weakness Muscle pain Prolonged fatigue after levels of exercise Generalized headaches Migratory pain in joints without swelling or redness Sleep disturbance Main symptom complex developing over a few hours or a few days

Neuropsychologic complaints Abnormal sensitivity to light Transient visual scotomata Excessive irritability Inability to concentrate Difficulty thinking Depression Confusion Forgetfulness

71 23

18 26 46 10

100

44 10 8

39

36 21 26 13

5

8 18 10 26 18 21 92

11 85 85 81 85

100 14 74 91 14

64 39 77 92 81 80 80 81

STRATEGIES IDENTIFYING CFS 343

Over the past 3 years, two of the respondents had not been to any medical doctors. The remaining 37 respondents had been to a total of 251 physicians for CFS diagnostic evaluation or treatment (M = 6.4) (range 0-30) over the past 3 years. Eighty-one of these physicians (or 32%) did not believe that the respondents had CFS (M = 2.1) (range 0-19). In addition, 59% of the respondents visited at least one medical doctor during the past 3 years who did not believe the respondents had CFS.

Discussion

There were several principal findings from this study. First, it is possible to reach the majority of CFS-afflicted people through the use of telephone calls. It is important to recognize that a high percentage of these individuals do have answering machines, and they often do screen their calls. Still, within eight attempts to reach the individuals, it was possible to reach the vast majority of the sample. Therefore, the use of the telephone for contacting CFS-afflicted people seems to be an effective method.

A second important finding was that the CFS-afflicted individuals had been to 251 physicians over the past 3 years, and 81 (or 32%) of these doctors did not feel that the respondents had CFS. In addition, 59% of the respondents had at least one medical doctor not believe that they had CFS. Many of the respondents informed us that they were not satisfied with the medical care they received or that their physicians frequently did not believe in their illness. Some individuals mentioned to us that they did not have the economic resources needed to access medical care. Others were reluc- tant to use medical personnel, particularly when their physicians had been skeptical of the authenticity of their disease. In addition, medical personnel who are skeptical of the evidence of CFS might not identify cases among their clients. These reasons might account for the lower rates of prevalence found within those studies that relied on medical personnel referral.

There were a number of methodological problems with the present study. The sample size was small, and clearly, the issues probed by this preliminary investigation need further study with larger samples. The lack of independent confirmation of medical and psychiatric status represents a serious shortcoming of the present study. In other words, it is possible that at least some of the individuals in our sample did not have CFS. However, the fact that all individuals had been diagnosed by at least one physician sug- gests that most in our sample probably had CFS. It could also be argued that the study should have been limited to only those participants who met Holmes et ale’s (1988) strict criteria for CFS. There is considerable controversy about this definition, and it is probable that in the future a less stringent definition will be employed using fewer minor symptoms, as in the British and Australian definitions (Katon & Russo, 1992; Straus, 1992). We did evaluate the data using the stringent criteria of Holmes et al. (1988), and findings similar to those reported in this paper were found.

Our research leads us to the conclusion that although it is very difficult to contact all CFS-afflicted individuals in prevalence studies, repeated telephone calls can be used to contact the large majority of cases. The need for a community-based epidemiological study would help in clarifying the discrepant CFS prevalence rates that were mentioned in the introduction. We believe that sole reliance on physician referral might have led to an underrepresentation of cases, but firm conclusions will need to wait until a community-based epidemiological study is conducted.

344 JASON, FITZGIBBON, TAYLOR, JOHNSON, AND SALINA

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