Wichita Clinical Study

The Wichita Clinical Study was a research study conducted by William Reeves and his chronic fatigue syndrome (CFS) program department at the Centers for Disease Control & Prevention. From December 2002 to July 2003 in Wichita, Kansas, USA, a 2-day in-hospital clinical assessment study was undertaken. The main objective of the study was to characterize the physiologic status of subjects with CFS, and to test the application of the 1994 CFS criteria to standardized reproducible criteria. The study results were published in the BMC Medicine in 2005.

The complete data set is available on the CDC Wichita Clinical Study Data Access website.

Study Groups
The study enrolled 227 people and classified them into five study groups based on specific criteria:


 * CFS group - patients who met the 1994 CFS case definition, also known as the Fukuda criteria case definition - 58 subjects
 * CFS-MDDm group - patients who met the 1994 CFS case definition except that a major depressive disorder with melancholic features was identified - 27 subjects
 * ISF group - patients who are chronically fatigued but not meeting the CFS case definition because of insufficient number of symptoms or fatigue severity - 59 subjects
 * ISF-MDDm group - patients who are chronically fatigued but with an insufficient number of symptoms or fatigue severity and a major depressive disorder with melancholic features - 28 subjects
 * NF group - patients who are non-fatigued controls matched to CFS subjects on age, race/ethnicity, sex, and body mass index - 55 subjects

Each participant's group assignment was blinded (that is, not known) to the researcher performing the evaluations.

Assessment
Testing included:
 * Demographics
 * Multidimensional Fatigue Inventory-20 (MFI)
 * 36-item Short-Form Health Survey (SF-36)
 * CDC 2005 Symptom Inventory for CFS
 * Physical Examination including a 30-minute recumbent blood pressure and heart rate, and 5-minute standing blood pressure and heart rate.
 * Laboratory Tests including a complete blood count with differential, c-reactive protein, alanine aminotransferase, albumin, alkaline phosphatase, asparatate aminotransferase, serum glutamic aminotransferase, total bilirubin, calcium, carbon dioxide, chloride, creatinine, glucose, potassium, total protein, sodium, blood urea nitrogen, and urinalysis.
 * Gynecological History
 * Medication Usage, including current prescribed and over-the-counter medications and dietary supplements
 * Tobacco Questionnaire - smoking status and the use of tobacco products
 * Endocrine and cortisol levels
 * Catecholamines - Plasma basal catecholamine, metanephrine, normetanephrine and neuropeptide; and morning plasma rennin and serum aldosterone
 * Cytokine levels - IL-6 (interleukin 6), TNF-alpha (tumor necrosis factor), and IL-1 beta
 * Cambridge Neuropsychological Test Automated Battery (CANTAB)
 * Wechsler Adult Intelligence Scale – Revised (WAIS-R)
 * Reading Subtest of Wide-Range Achievement Test (WRAT3)
 * Epworth Sleepiness Scale (ESS)
 * Nap Questionnaire- collected information related to four 20-minute naps that were part of the study
 * Sleep Questionnaire - pre-sleep questionnaire and post-sleep questionnaire, which collected information regarding subjects’ first and second overnight sleep study.
 * Polysomnographic and Multiple Sleep Latency Test (MSLT) Published Results, 2006
 * Self-Rating Depression Scale (SDS)
 * Davidson Trauma Scale (DTS)
 * General Health Questionnaire (GHQ-30)
 * Childhood Trauma Questionnaire (CTQ)
 * Traumatic Life Events Questionnaire (TLEQ)
 * Life Experiences Survey (LES)
 * Perceived Stress Scale (PSS)
 * Ways of Coping Questionnaire (WCQ)
 * Spielberger State-Trait Anxiety Inventory (STAI)
 * Single Nucleotide Polymorphism (SNP)- selected polymorphisms in a small set of genes representing immune and central nervous system functions, particularly Hypothalamic-pituitary-adrenal axis (HPA) to identify genetic variants associated with CFS or quantitative measures of major domains of CFS.
 * Gene Expression - Subjects’ peripheral blood mononuclear cells were analyzed to examine global gene expression.

Conclusion
The conclusion of the Wichita Clinical Study published in 2005 stated: "The empirical definition includes all aspects of CFS specified in the 1994 case definition and identifies persons with CFS in a precise manner that can be readily reproduced by both investigators and clinicians."

In 2006, Reeves spoke at The National Press Club as part of a "Chronic Fatigue Syndrome Awareness Campaign". Using results from the Wichita Clinical Study, he stated: "When we completed the medical workups of people in Wichita to confirm that they had CFS, we found that only half of those with the illness had consulted a physician for the illness. We found that only 16 percent had been diagnosed and treated for CFS...We found that a quarter of the people with CFS are either unemployed or receiving disability...We’ve documented, as have others, that the level of functional impairment in people who suffer from CFS is comparable to multiple sclerosis, AIDS, end-stage renal failure, [or] chronic obstructive pulmonary disease. The disability is equivalent to that of some well-known, very severe medical conditions.”