Leonard Jason, Ph.D., is among the most prolific of all CFIDS researchers. For more than a decade, Jason and his team at DePaul University’s Center for Community Research have worked to define the scope and impact of CFIDS worldwide.
In recognition of his contribution to the CFIDS community, Jason received the Dutch ME-Foundation International ME-Award for 2003 for outstanding work in the past 10 years in the field of chronic fatigue syndrome (CFS). The award came with a prize of 5,000 Euros as well as specially commissioned piece of artwork by Marika Meershoek.
Q: How did you get involved in CFS research?
A: In the early 1990s, Judy Richman, a sociologist at the University of Illinois–Chicago, and I began discussing the prevalence data for CFS (then believed to be about 4–9 cases per 100,000 people), which suggested that CFS was a relatively rare disorder that affected primarily white, middle-class, women. When we looked closely at the way the data were collected, we realized that there were serious methodological problems with this research.
The epidemiological studies derived their samples from physician referrals in hospital and community-based clinics. These studies under-represented low-income and under-served minorities, people who manifest higher levels of chronic illness while also being less likely to have access to the health care system — and who are thus less likely to be counted in prevalence rates derived from treatment sources.
These studies also underestimated the prevalence of CFS in the general population because they depended on diagnoses by healthcare providers who discounted the existence of the illness and would thus fail to diagnose it.
Q. How did you go about finding the real prevalence figures?
A: We began our work in this area in 1991. In our first epidemiology study, we directly surveyed nurses. Out of a sample of 3,400,202 nurses (6 percent) indicated that they had experienced debilitating fatigue for six months or longer. Thirty-seven nurses met case criteria for current CFS, yielding a prevalence rate of 1,088 per 100,000.
In 1993, we collected pilot data for the presence of CFS in a random community sample of 1,031 people (with funding from The CFIDS Association of America). Sixty-four percent of the fatigued group indicated that they had no current medical doctor overseeing their illness. The DePaul University research team found a prevalence rate of 200 per 100,000, a number higher than one would have expected, given rates from past epidemiological studies.
After many efforts to get funding, we finally were successful in obtaining a National Institutes of Health (NIH) grant. From 1995 until 1998, we attempted to contact a sample of 28,673 households in Chicago by telephone. Of that sample, 18,675 individuals were screened for CFS symptomatology. The sample was stratified to ensure that it reflected the diverse ethnic and socioeconomic groups comprising the Chicago general population.
Approximately 420 per 100,000 of the sample were determined to have CFS, and rates of CFS were higher among Latino and African-American respondents when compared to white respondents. These data suggested that there might be as many as 800,000 adults in the U.S. with this syndrome, suggesting that it is one of the more common chronic health conditions. Data were also collected for youth, and the findings indicated a CFS prevalence of .06 percent, or 60 cases per 100,000.
Q: Epidemiological studies are not always seen as “sexy” by a patient community eager for treatments and a cure. Why are they so important?
A: Quite simply, if there are few cases of CFS in the population, it is more difficult to generate funds for research and treatment. Without funding, progress is difficult if not impossible.
It’s easier to make the case for funding when you’re dealing with a patient population of 800,000 people than it is when you’re talking about a rare disorder affecting a fraction of that figure.
Epidemiological studies also aid the design of other research. The better we know the patient population, the better the overall science will be. Most existing prevalence studies have had poor sampling plans and systematic biases that excluded certain people (i.e., studies were conducted in medical settings, so that they likely excluded people of lower socioeconomic status and people of color who were less likely to have access to health care).
In addition, there is a vital need to examine the incidence and course of CFS over time, particularly in random, community-based, multi-ethnic populations.
A recent technical report issued by the Agency for Healthcare Research and Quality (Defining and Managing Chronic Fatigue Syndrome, 2001) concluded that estimates of recovery/improvement or relapse from CFS are not possible because there are so few natural history studies and those that are available have involved selected referral populations. This report recommended that there was a need for studies to properly determine the long-term natural history of CFS.
This report clearly indicated the need to conduct epidemiologic studies that provide estimates of CFS incidence in community-based samples, and to identify risk factors for prognosis and onset of CFS in socioeconomically diverse samples.
Q: What is your research team focusing on now?
A: We believe that the most important work that is now needed in the field is to develop sub-types within the CFS population, and our research group is currently working on this topic.
Individuals with CFS have been found to differ with respect to many characteristics. As a result of this heterogeneity, findings emerging from studies in a number of areas are, at best, discrepant, and at worst, contradictory. Heterogeneity among participant groups can also contribute to a lack of observable abnormalities in some laboratory studies.
One central, methodological explanation for observations of discrepant findings across studies involves issues related to sampling and participant selection. A majority of investigations have employed non-random, medically-referred samples. There probably are different types of illnesses now contained within the CFS construct, which makes it even more difficult to identify commonalities in all people with this diagnosis.
Q: Other than funding and better study design, what does the CFS research field need most?
A: Given the prevalence and seriousness of this disorder, there is a clear need for advocacy, in which the general public and the medical community become better educated about the problems and difficulties associated with CFS.
Some patients with CFS need assistance from others in order to complete daily living tasks, while others need basic medical services and housing. Unfortunately, there are few funding opportunities for these more innovative types of social and community interventions.
Given that this syndrome is one of the more common chronic health conditions, and the documented personal and familial costs associated with this condition, there is a clear need for public policy officials to devote more resources to developing a better infrastructure of support for individuals with CFS.
Dr. Jason is co-author of the new “Handbook of Chronic Fatigue Syndrome” (Jason, Patricia A. Fennell, Renee R. Taylor; 2003; John Wiley & Sons). It is available through Amazon.com and bookstores.
This article originally appeared in the Summer 2003 issue of The CFIDS Chronicle. It has been reprinted with the permission of The CFIDS Association of America. For more information, call the Association at 800-442-3437 or visit www.cfids.org.