Mental illness in metropolitan, urban and rural Georgia populations.

BACKGROUND: Mental illness represents an important public health problem. Local-level data concerning mental illness in different populations (e.g., socio-demographics and residence--metropolitan/urban/rural) provides the evidence-base for public health authorities to plan, implement and evaluate control programs. This paper describes prevalence and covariates of psychiatric conditions in Georgia populations in three defined geographic areas. METHODS: Data came from the Georgia population-based random-digit-dialing study investigating unwellness and chronic fatigue syndrome (CFS) in Georgia populations of three defined geographic areas (metropolitan, urban, and rural). Respondents were screened for symptoms of fatigue, sleep, cognition, and pain at household screening interviews, and a randomly selected sample completed detailed individual phone interviews. Based on the detailed phone interviews, we conducted one-day clinical evaluations of 292 detailed interview participants classified as unwell with a probable CFS (i.e. CFS-like; a functional somatic syndrome), 268 classified as other unwell, and 223 well (matched to CFS-like). Clinical evaluation included psychiatric classification by means of the Structured Clinical Interview for DSM (SCID). To derive prevalence estimates we used sample weighting to account for the complexity of the multistage sampling design. We used 2- and 3-way table analyses to examine socio-demographic and urbanicity specific associations and multiple logistic regression to calculate adjusted odds ratios. RESULTS: Anxiety and mood disorders were the most common psychiatric conditions. Nineteen percent of participants suffered a current anxiety disorder, 18% a mood disorder and 10% had two or more conditions. There was a significant linear trend in occurrence of anxiety or mood disorders from well to CFS-like. The most common anxiety disorders were post-traumatic stress disorder (PTSD) (6.6%) and generalized anxiety disorder (GAD) (5.8%). Logistic regression showed that lower education and female sex contributed significantly to risk for both PTSD and GAD. In addition, rural/urban residence and Hispanic ethnicity were associated with PTSD. We defined moderate to severe depression as Major Depressive Disorder or a Zung score>60 and logistic regression found lower education to be significantly associated but sex, age and urbanicity were not. CONCLUSIONS: Overall occurrence of anxiety and mood disorders in Georgia mirrored national findings. However, PTSD and GAD occurred at twice the published national rates (3.6 and 2.7%, respectively). State and local prevalence and associations with education, sex and urbanicity comprise important considerations for developing control programs. The increased prevalence of anxiety and mood disorders in people with a functional somatic syndrome (or CFS-like illness) is important for primary care providers, who should consider additional psychiatric screening or referral of individuals presenting with somatoform symptoms.

Cumulative life stress in chronic fatigue syndrome.

We studied the impact of cumulative life stress on CFS in a population-based study. We found that exposure to stressors was significantly more common in persons with CFS compared to NF controls; those with CFS reported experiencing significantly higher levels of psychological distress. Also, post-traumatic stress disorder was significantly more common in people with CFS. These results not only corroborate findings from other studies but, importantly, extend those by: a) measuring a comprehensive spectrum of stress variables, b) for the first time presenting data on stress in a population-based study, thus minimizing the effects of recruitment bias, and c) diagnosing CFS by means of standardized, validated scales, thus allowing replication and extension of our findings. Stress may be an important factor in the pathophysiology of CFS. Consequently, future studies should provide a more detailed understanding of the processes that lead from stress to CFS using longitudinal designs.

Absence of evidence of xenotropic murine leukemia virus-related virus infection in persons with chronic fatigue syndrome and healthy controls in the United States.

BACKGROUND: XMRV, a xenotropic murine leukemia virus (MuLV)-related virus, was recently identified by PCR testing in 67% of persons with chronic fatigue syndrome (CFS) and in 3.7% of healthy persons from the United States. To investigate the association of XMRV with CFS we tested blood specimens from 51 persons with CFS and 56 healthy persons from the US for evidence of XMRV infection by using serologic and molecular assays. Blinded PCR and serologic testing were performed at the US Centers for Disease Control and Prevention (CDC) and at two additional laboratories. RESULTS: Archived blood specimens were tested from persons with CFS defined by the 1994 international research case definition and matched healthy controls from Wichita, Kansas and metropolitan, urban, and rural Georgia populations. Serologic testing at CDC utilized a Western blot (WB) assay that showed excellent sensitivity to MuLV and XMRV polyclonal or monoclonal antibodies, and no reactivity on sera from 121 US blood donors or 26 HTLV-and HIV-infected sera. Plasma from 51 CFS cases and plasma from 53 controls were all WB negative. Additional blinded screening of the 51 cases and 53 controls at the Robert Koch Institute using an ELISA employing recombinant Gag and Env XMRV proteins identified weak seroreactivity in one CFS case and a healthy control, which was not confirmed by immunofluorescence. PCR testing at CDC employed a gag and a pol nested PCR assay with a detection threshold of 10 copies in 1 ug of human DNA. DNA specimens from 50 CFS patients and 56 controls and 41 US blood donors were all PCR-negative. Blinded testing by a second nested gag PCR assay at the Blood Systems Research Institute was also negative for DNA specimens from the 50 CFS cases and 56 controls. CONCLUSIONS: We did not find any evidence of infection with XMRV in our U.S. study population of CFS patients or healthy controls by using multiple molecular and serologic assays. These data do not support an association of XMRV with CFS.

Personality features and personality disorders in chronic fatigue syndrome: a population-based study.

BACKGROUND: Chronic fatigue syndrome (CFS) presents unique diagnostic and management challenges. Personality may be a risk factor for CFS and may contribute to the maintenance of the illness. METHODS: 501 study participants were identified from the general population of Georgia: 113 people with CFS, 264 with unexplained unwellness but not CFS (insufficient fatigue, ISF) and 124 well controls. We used the Personality Diagnostic Questionnaire, 4th edition, to evaluate DSM-IV personality disorders. We used the NEO Five-Factor Inventory to assess personality features (neuroticism, extraversion, openness, agreeableness and conscientiousness). The Multidimensional Fatigue Inventory measured 5 dimensions of fatigue, and the Medical Outcomes Survey Short Form 36 measured 8 dimensions of functional impairment. RESULTS: Twenty-nine percent of the CFS cases had at least 1 personality disorder, compared to 28% of the ISF cases and 7% of the well controls. The prevalence of paranoid, schizoid, avoidant, obsessive-compulsive and depressive personality disorders were significantly higher in CFS and ISF compared to the well controls. The CFS cases had significantly higher scores on neuroticism, and significantly lower scores on extraversion than those with ISF or the well controls. Personality features were correlated with selected composite characteristics of fatigue. CONCLUSIONS: Our results suggest that CFS is associated with an increased prevalence of maladaptive personality features and personality disorders. This might be associated with being noncompliant with treatment suggestions, displaying unhealthy behavioral strategies and lacking a stable social environment. Since maladaptive personality is not specific to CFS, it might be associated with illness per se rather than with a specific condition.

Association of childhood trauma with cognitive function in healthy adults: a pilot study.

BACKGROUND: Animal and human studies suggest that stress experienced early in life has detrimental consequences on brain development, including brain regions involved in cognitive function. Cognitive changes are cardinal features of depression and posttraumatic stress disorder. Early-life trauma is a major risk factor for these disorders. Only few studies have measured the long-term consequences of childhood trauma on cognitive function in healthy adults. METHODS: In this pilot study, we investigated the relationship between childhood trauma exposure and cognitive function in 47 healthy adults, who were identified as part of a larger study from the general population in Wichita, KS. We used the Cambridge Neuropsychological Test Automated Battery (CANTAB) and the Wide-Range-Achievement-Test (WRAT-3) to examine cognitive function and individual achievement. Type and severity of childhood trauma was assessed by the Childhood Trauma Questionnaire (CTQ). Data were analyzed using multiple linear regression on CANTAB measures with primary predictors (CTQ scales) and potential confounders (age, sex, education, income). RESULTS: Specific CTQ scales were significantly associated with measures of cognitive function. Emotional abuse was associated with impaired spatial working memory performance. Physical neglect correlated with impaired spatial working memory and pattern recognition memory. Sexual abuse and physical neglect were negatively associated with WRAT-3 scores. However, the association did not reach the significance level of p < 0.01. CONCLUSIONS: Our results suggest that physical neglect and emotional abuse might be associated with memory deficits in adulthood, which in turn might pose a risk factor for the development of psychopathology.

Validation of ECG-derived sleep architecture and ventilation in sleep apnea and chronic fatigue syndrome.

PURPOSE: Newly developed algorithms putatively derive measures of sleep, wakefulness, and respiratory disturbance index (RDI) through detailed analysis of heart rate variability (HRV). Here, we establish levels of agreement for one such algorithm through comparative analysis of HRV-derived values of sleep-wake architecture and RDI with those calculated from manually scored polysomnographic (PSG) recordings. METHODS: Archived PSG data collected from 234 subjects who participated in a 3-day, 2-night study characterizing polysomnographic traits of chronic fatigue syndrome were scored manually. The electrocardiogram and pulse oximetry channels were scored separately with a novel scoring algorithm to derive values for wakefulness, sleep architecture, and RDI. RESULTS: Four hundred fifty-four whole-night PSG recordings were acquired, of which, 410 were technically acceptable. Comparative analyses demonstrated no difference for total minutes of sleep, wake, NREM, REM, nor sleep efficiency generated through manual scoring with those derived through HRV analyses. When NREM sleep was further partitioned into slow-wave sleep (stages 3-4) and light sleep (stages 1-2), values calculated through manual scoring differed significantly from those derived through HRV analyses. Levels of agreement between RDIs derived through the two methods revealed an R = 0.89. The Bland-Altman approach for determining levels of agreement between RDIs generated through manual scoring with those derived through HRV analysis revealed a mean difference of -0.7 +/- 8.8 (mean +/- two standard deviations). CONCLUSION: We found no difference between values of wakefulness, sleep, NREM, REM sleep, and RDI calculated from manually scored PSG recordings with those derived through analyses of HRV.

U.S. healthcare providers' knowledge, attitudes, beliefs, and perceptions concerning Chronic Fatigue Syndrome.

BACKGROUND: Chronic fatigue syndrome (CFS) is a debilitating illness with particular difficulties for healthcare providers because there are no diagnostic signs or laboratory tests and because management aims to merely improve symptoms. Further complicating management, healthcare providers' awareness concerning CFS has not been rigorously assessed. The present study aimed to ascertain United States (U.S.) healthcare providers' awareness of CFS and to assess their knowledge, attitudes, and beliefs (KAB) related to diagnosis and management of the illness. This information forms the foundation for developing CFS educational strategies. METHODS: We combined convenience and probability samples to measure CFS KAB among healthcare providers. In the convenience sample, 1,255 healthcare providers (81% response rate) from 13 professional conferences completed a 12-item form. Descriptive statistics were reported for 9 KAB item responses and chi-square tests were performed for examining their association with giving a diagnosis of CFS. We used principal component analysis to construct multidimensional subscales and perform a general linear model to examine factors associated with subscales. The probability sample involved data on 15 CFS-specific questions from 2006 and 2007 DocStyles web-based panel surveys collected from 2,750 physicians (average response rate 55%). We calculated descriptive and chi-square statistics. The significance was set at two-tailed with the alpha level of 0.05. RESULTS: Healthcare providers in both samples were aware of CFS and exhibited a high level of knowledge. Overall, 96% of respondents in the DocStyles (probability) sample had heard about CFS. Healthcare providers in the conference (convenience) sample demonstrated good KAB scores; physicians' scores were highest on KAB scales and lowest in perception. Nurses' scores were lowest in knowledge. More than 40% of physicians reported ever giving a CFS diagnosis and in the DocStyles (probability) sample more than 80% of physicians correctly identified CFS symptoms. Physicians reported professional journals, the Internet, and continuing education programs as the top 3 sources from which they obtain CFS information. CONCLUSIONS: Findings from these combined samples fill a gap in the evidence-base of U.S. healthcare providers' and knowledge, attitudes, and beliefs concerning CFS. Importantly, respondents in both samples expressed similar knowledge, attitudes, beliefs and perceptions. Awareness was high and negative attitudes were low. The primary areas for future education should address diagnosis and management of CFS and should be delivered through those venues providers indicated they primarily use. Data from this study provide a benchmark for evaluation the success of these future efforts.

Hypersomnolence and sleep-related complaints in metropolitan, urban, and rural Georgia.

Persistent daytime hypersomnolence is associated with significant morbidity and mortality, but its prevalence in the population has been poorly documented. This study sought to characterize the prevalence of persistent daytime hypersomnolence, difficulties initiating and maintaining sleep, unrefreshing sleep, snoring, and the presence of physician-diagnosed sleep disorders in metropolitan, urban, and rural US Georgia populations. Between September 2004 and July 2005, a total of 6,530 randomly selected well and unwell adults, identified by screening interviews of 10,837 households (contacted by random digit dialing), completed a detailed phone interview. Sixteen percent reported persistent problems staying awake during the day; 26% reported persistent problems falling asleep at night; 31% experienced problems sleeping through the night; 34% were bothered by unrefreshing sleep; and 33% reported that they snored. In spite of the high occurrence of reported persistent sleep problems, only 10% of the survey participants reported having been diagnosed with a sleep disorder. These study findings highlight the need for increased public and clinician awareness with respect to proactively identifying signs and symptoms of sleep disorders, a better understanding of their adverse impact upon morbidity and mortality, and their negative impact upon socioeconomic and academic potential.

An evaluation of exclusionary medical/psychiatric conditions in the definition of chronic fatigue syndrome.

BACKGROUND: The diagnosis of chronic fatigue syndrome (CFS) in research studies requires the exclusion of subjects with medical and psychiatric conditions that could confound the analysis and interpretation of results. This study compares illness parameters between individuals with CFS who have and those who do not have exclusionary conditions. METHODS: We used a population-based telephone survey of randomly selected individuals, followed by a clinical evaluation in the study metropolitan, urban, and rural counties of Georgia, USA. The medical and psychiatric histories of the subjects were examined and they underwent physical and psychiatric examinations and laboratory screening. We also employed the multidimensional fatigue inventory (MFI), the medical outcomes survey short form-36 (SF-36) and the US Centres for Disease Control and Prevention symptom inventory (SI). RESULTS: Twenty-nine percent (1,609) of the 5623 subjects who completed the detailed telephone interview reported exclusionary diagnoses and we diagnosed an exclusionary condition in 36% of 781 clinically evaluated subjects. Both medical and psychiatric exclusionary conditions were more common in women, blacks and participants from rural areas. Subjects with and without exclusions had similar levels of fatigue and impairment as measured by the MFI and SF-36; those with CFS-like illness (not meeting the formal CFS definition) were more likely to have an exclusionary diagnosis. After adjusting for demographics, body mass index, fatigue subscales, SF-36 subscales and CFS symptoms, CFS-like illness did not remain significantly associated with having an exclusionary diagnosis. CONCLUSION: Medical and psychiatric illnesses associated with fatigue are common among the unwell. Those who fulfill CFS-like criteria need to be evaluated for potentially treatable conditions. Those with exclusionary conditions are equally impaired as those without exclusions.

Chronic fatigue syndrome and high allostatic load: results from a population-based case-control study in Georgia.

OBJECTIVE: To confirm the association of chronic fatigue syndrome (CFS) with high allostatic load (AL) level, examine the association of subsyndromal CFS with AL level, and investigate the effect of depression on these relationships and the association of AL with functional impairment, fatigue, symptom severity, fatigue duration, and type of CFS onset. AL represents the cumulative physiologic effect of demands to adapt to stress. METHODS: Population-based case-control study of 83 persons with CFS, 202 persons with insufficient symptoms or fatigue for CFS (ISF), and 109 well controls living in Georgia. Unconditional logistic regression was used to generate odds ratios (ORs) as measures of the association of AL with CFS. RESULTS: Relative to well controls, each 1-point increase in allostatic load index (ALI) was associated with a 26% increase in likelihood of having CFS (OR(adjusted) = 1.26, 95% Confidence Interval (CI) = 1.00, 1.59). This association remained in the presence and absence of depression (OR(adjusted) = 1.35, CI = 1.07, 1.72; OR(adjusted) = 1.35, CI = 1.10, 1.65). Compared with the ISF group, each 1-point increase in ALI was associated with a 10% increase in likelihood of having CFS (OR(adjusted) = 1.10, CI = 0.93, 1.31). Among persons with CFS, the duration of fatigue was inversely correlated with ALI (r = -.26, p = .047). CONCLUSIONS: Compared with well controls, persons with CFS were significantly more likely to have a high AL. AL increased in a gradient across well, ISF, and CFS groups.

Psychiatric comorbidity in persons with chronic fatigue syndrome identified from the Georgia population.

OBJECTIVE: To compare the prevalence of psychiatric disorders in persons with chronic fatigue syndrome (CFS) identified from the general population and a chronically ill group of people presenting with subsyndromic CFS-like illness ("insufficient symptoms or fatigue" (ISF)). Previous studies in CFS patients from primary and tertiary care clinics have found high rates of psychiatric disturbance, but this may reflect referral bias rather than true patterns of comorbidity with CFS. METHODS: We used random digit dialing to identify unwell individuals. A detailed telephone interview identified those with CFS-like illness. These individuals participated in a 1-day clinical evaluation to confirm CFS or ISF status. We identified 113 cases of CFS and 264 persons with ISF. To identify current and lifetime psychiatric disorders, participants completed the Structured Clinical Interview for DSM-IV. RESULTS: Sixty-four persons (57%) with CFS had at least one current psychiatric diagnosis, in contrast to 118 persons (45%) with ISF. One hundred one persons (89%) with CFS had at least one lifetime psychiatric diagnosis compared with 208 persons (79%) with ISF. Of note, only 11 persons (9.8%) with CFS and 25 persons (9.5%) with ISF reported having seen a mental healthcare specialist during the past 6 months. CONCLUSIONS: Our findings indicate that current and lifetime psychiatric disorders commonly accompany CFS in the general population. Most CFS cases with comorbid psychiatric conditions had not sought appropriate help during the past 6 months. These results demonstrate an urgent need to address psychiatric disorders in the clinical care of CFS cases.

Association of peripheral inflammatory markers with chronic fatigue in a population-based sample.

Alterations in the innate immune response may contribute to the pathogenesis of chronic fatigue syndrome (CFS). However, studies have been limited by small sample sizes, use of patients from tertiary care settings, inappropriate selection of controls, and failure to control for confounding demographic, medical and behavioral factors independently associated with immune activity. It is also not known whether specific symptoms account for observed associations between CFS and the innate immune response. To address these limitations, the current study examined plasma concentrations of high-sensitivity c-reactive protein (hs-CRP), white blood cell count (WBC) and a combined inflammation factor in a large population-based sample. Log-transformed mean plasma concentrations of hs-CRP were increased in subjects with CFS (n=102) and in subjects with unwellness symptoms that did not meet diagnostic criteria for CFS (defined as "insufficient fatigue" [ISF]) (n=240) when compared to subjects who were well (n=115). Log transformed WBC was increased in ISF and was increased at a trend level in CFS. The combined inflammation factor was increased in both CFS and ISF. Subjects with CFS and ISF did not differ on any of the inflammation measures. In the entire subject population, the physical component summary score (PCS), but not the mental component summary score (MCS), from the Medical Outcomes Study Short Form-36 (SF-36) was negatively associated with each of the inflammation measures. Depressive symptoms were also associated with increased log hs-CRP. After adjustment for age, sex, race, location of residence, BMI, depressive status and immune-modulating medications, subjects classified as ISF continued to demonstrate increased log hs-CRP, WBC and elevations on the inflammation factor when compared to well controls; however, associations between CFS and log hs-CRP and the inflammation factor were no longer statistically significant. After adjustment, PCS score also remained independently associated with each of the inflammation measures. These findings support a role for innate immune activation in unexplained fatigue and unwellness, but do not suggest that immune activation is specific to CFS.

Electroencephalographic correlates of Chronic Fatigue Syndrome.

BACKGROUND: Unremitting fatigue and unrefreshing sleep, hallmark traits of Chronic Fatigue Syndrome (CFS), are also pathognomonic of sleep disorders. Yet, no reproducible perturbations of sleep architecture, multiple sleep latency times or Epworth Sleepiness Scores are found to be associated consistently with CFS. This led us to hypothesize that sleep homeostasis, rather than sleep architecture, may be perturbed in CFS. To probe this hypothesis, we measured and compared EEG frequencies associated with restorative sleep between persons with CFS and matched controls, both derived from a population-based sample. METHODS: We evaluated overnight polysomnography (PSG) in 35 CFS and 40 control subjects. PSG records were manually scored and epochs containing artifact removed. Fast Fourier Transformation was utilized to deconstruct individual EEG signals into primary frequency bands of alpha, delta, theta, sigma, and beta frequency domains. The spectral power of each frequency domain for each sleep state was compared between persons with CFS and matched controls. RESULTS: In persons with CFS, delta power was diminished during slow wave sleep, but elevated during both stage 1 and REM. Alpha power was reduced during stage 2, slow wave, and REM sleep. Those with CFS also had significantly lower theta, sigma, and beta spectral power during stage 2, Slow Wave Sleep, and REM. DISCUSSION: Employing quantitative EEG analysis we demonstrate reduced spectral power of cortical delta activity during SWS. We also establish reduced spectral power of cortical alpha activity, with the greatest reduction occurring during REM sleep. Reductions in theta, beta, and sigma spectral power were also apparent. CONCLUSION: Unremitting fatigue and unrefreshing sleep, the waking manifestations of CFS, may be the consequence of impaired sleep homeostasis rather than a primary sleep disorder.

Replication of an empirical approach to delineate the heterogeneity of chronic unexplained fatigue.

BACKGROUND: Chronic fatigue syndrome (CFS) is defined by self-reported symptoms. There are no diagnostic signs or laboratory markers, and the pathophysiology remains inchoate. In part, difficulties identifying and replicating biomarkers and elucidating the pathophysiology reflect the heterogeneous nature of the syndromic illness CFS. We conducted this analysis of people from defined metropolitan, urban, and rural populations to replicate our earlier empirical delineation of medically unexplained chronic fatigue and CFS into discrete endophenotypes. Both the earlier and current analyses utilized quantitative measures of functional impairment and symptoms as well as laboratory data. This study and the earlier one enrolled participants from defined populations and measured the internal milieu, which differentiates them from studies of clinic referrals that examine only clinical phenotypes. METHODS: This analysis evaluated 386 women identified in a population-based survey of chronic fatigue and unwellness in metropolitan, urban, and rural populations of the state of Georgia, USA. We used variables previously demonstrated to effectively delineate endophenotypes in an attempt to replicate identification of these endophenotypes. Latent class analyses were used to derive the classes, and these were compared and contrasted to those described in the previous study based in Wichita, Kansas. RESULTS: We identified five classes in the best fit analysis. Participants in Class 1 (25%) were polysymptomatic, with sleep problems and depressed mood. Class 2 (24%) was also polysymptomatic, with insomnia and depression, but participants were also obese with associated metabolic strain. Class 3 (20%) had more selective symptoms but was equally obese with metabolic strain. Class 4 (20%) and Class 5 (11%) consisted of nonfatigued, less symptomatic individuals, Class 4 being older and Class 5 younger. The classes were generally validated by independent variables. People with CFS fell equally into Classes 1 and 2. Similarities to the Wichita findings included the same four main defining variables of obesity, sleep problems, depression, and the multiplicity of symptoms. Four out of five classes were similar across both studies. CONCLUSION: These data support the hypothesis that chronic medically unexplained fatigue is heterogeneous and can be delineated into discrete endophenotypes that can be replicated. The data do not support the current perception that CFS represents a unique homogeneous disease and suggests broader criteria may be more explanatory. This replication suggests that delineation of endophenotypes of CFS and associated ill health may be necessary in order to better understand etiology and provide more patient-focused treatments.

Further validation of the Multidimensional Fatigue Inventory in a US adult population sample.

BACKGROUND: The Multidimensional Fatigue Inventory (MFI-20) was developed in 1995. Since then, it has been widely used in cancer research and cancer-related illnesses but has never been validated in fatiguing illnesses or in a large US population-selected sample. In this study, we sought to examine the reliability and validity of the MFI-20 in the population of the state of Georgia, USA. Further, we assessed whether the MFI-20 could serve as a complementary diagnostic tool in chronically fatigued and unwell populations. METHODS: The data derive from a cross-sectional population-based study investigating the prevalence of chronic fatigue syndrome (CFS) in Georgia. The study sample was comprised of three diagnostic groups: CFS-like (292), chronically unwell (269), and well (222). Participants completed the MFI-20 along with several other measures of psychosocial functioning, including the Medical Outcomes Survey Short Form-36 (SF-36), the Zung Self-Rating Depression Scale (SDS), and the Spielberger State-Trait Anxiety Inventory (STAI). We assessed the five MFI-20 subscales using several criteria: inter-item correlations, corrected item-total correlations, internal consistency reliability (Cronbach's alpha coefficients), construct validity, discriminant (known-group) validity, floor/ceiling effects, and convergent validity through correlations with the SF-36, SDS, and STAI instruments. RESULTS: Averaged inter-item correlations ranged from 0.38 to 0.61, indicating no item redundancy. Corrected item-total correlations for all MFI-20 subscales were greater than 0.30, and Cronbach's alpha coefficients achieved an acceptable level of 0.70. No significant floor/ceiling effect was observed. Factor analysis demonstrated factorial complexity. The MFI-20 also distinguished clearly between three diagnostic groups on all subscales. Furthermore, correlations with depression (SDS), anxiety (STAI), and functional impairment (SF-36) demonstrated strong convergent validity. CONCLUSIONS: This study provides support for the MFI-20 as a valuable tool when used in chronically unwell and well populations. It also suggests that the MFI-20 could serve as a complementary diagnostic tool in fatiguing illnesses, such as CFS.

Use of medications by people with chronic fatigue syndrome and healthy persons: a population-based study of fatiguing illness in Georgia.

BACKGROUND: Chronic fatigue syndrome (CFS) is a debilitating condition of unknown etiology and no definitive pharmacotherapy. Patients are usually prescribed symptomatic treatment or self-medicate. We evaluated prescription and non-prescription drug use among persons with CFS in Georgia and compared it to that in non-fatigued Well controls and also to chronically Unwell individuals not fully meeting criteria for CFS. METHODS: A population-based, case-control study. To identify persons with possible CFS-like illness and controls, we conducted a random-digit dialing telephone screening of 19,807 Georgia residents, followed by a detailed telephone interview of 5,630 to identify subjects with CFS-like illness, other chronically Unwell, and Well subjects. All those with CFS-like illness (n = 469), a random sample of chronically Unwell subjects (n = 505), and Well individuals (n = 641) who were age-, sex-, race-, and geographically matched to those with CFS-like illness were invited for a clinical evaluation and 783 participated (48% overall response rate). Clinical evaluation identified 113 persons with CFS, 264 Unwell subjects with insufficient symptoms for CFS (named ISF), and 124 Well controls; the remaining 280 subjects had exclusionary medical or psychiatric conditions, and 2 subjects could not be classified. Subjects were asked to bring all medications taken in the past 2 weeks to the clinic where a research nurse viewed and recorded the name and the dose of each medication. RESULTS: More than 90% of persons with CFS used at least one drug or supplement within the preceding two weeks. Among users, people with CFS used an average of 5.8 drugs or supplements, compared to 4.1 by ISF and 3.7 by Well controls. Persons with CFS were significantly more likely to use antidepressants, sedatives, muscle relaxants, and anti-acids than either Well controls or the ISF group. In addition, persons with CFS were significantly more likely to use pain-relievers, anti-histamines and cold/sinus medications than were Well controls. CONCLUSION: Medical care providers of patients with chronic fatigue syndrome should be aware of polypharmacy as a problem in such patients, and the related potential iatrogenic effects and drug interactions.

Are chronic fatigue and chronic fatigue syndrome valid clinical entities across countries and health-care settings?

OBJECTIVE: The validity of the diagnosis of chronic fatigue syndrome and related chronic fatigue states remains controversial, particularly in psychiatry. This project utilized international epidemiological and clinical research data to test construct validity across diagnostic categories, health-care settings and countries. Relevant demographic, symptom and diagnostic data were obtained from 33 studies in 21 countries. The subjects had fatigue lasting 1-6 months (prolonged fatigue), or >6 months (chronic fatigue), or met diagnostic criteria for chronic fatigue syndrome. METHOD: Common symptom domains were derived by factor analytic techniques. Mean scores on each symptom factor were compared across diagnostic categories, health-care settings and countries. RESULTS: Data were obtained on 37,724 subjects (n = 20,845 female, 57%), including from population-based studies (n = 15,749, 42%), studies in primary care (n = 19 472, 52%), and secondary or specialist tertiary referral clinics (n = 2503, 7%). The sample included 2013 subjects with chronic fatigue, and 1958 with chronic fatigue syndrome. A five-factor model of the key symptom domains was preferred ('musculoskeletal pain/fatigue', 'neurocognitive difficulties', 'inflammation', 'sleep disturbance/fatigue' and 'mood disturbance') and was comparable across subject groups and settings. Although the core symptom profiles were similar, some differences in symptoms were observed across diagnostic categories, health-care settings and between countries. CONCLUSIONS: The construct validity of chronic fatigue and chronic fatigue syndrome is supported by an empirically derived factor structure from existing international datasets.

Barriers to healthcare utilization in fatiguing illness: a population-based study in Georgia.

BACKGROUND: The purpose of this study was to determine the prevalence of barriers to healthcare utilization in persons with fatiguing illness and describe its association with socio-demographics, the number of health conditions, and frequency of healthcare utilization. Furthermore, we sought to identify what types of barriers interfered with healthcare utilization and why they occurred. METHODS: In a cross-sectional population-based survey, 780 subjects, 112 of them with chronic fatigue syndrome (CFS), completed a healthcare utilization questionnaire. Text analysis was used to create the emerging themes from verbatim responses regarding barriers to healthcare utilization. Multiple logistic regression was performed to examine the association between barriers to healthcare utilization and other factors. RESULTS: Forty percent of subjects reported at least one barrier to healthcare utilization. Of 112 subjects with CFS, 55% reported at least one barrier to healthcare utilization. Fatiguing status, reported duration of fatigue, insurance, and BMI were significant risk factors for barriers to healthcare utilization. After adjusting for socio-demographics, medication use, the number of health problems, and frequency of healthcare utilization, fatiguing status remained significantly associated with barriers to healthcare utilization. Subjects with CFS were nearly 4 times more likely to forego needed healthcare during the preceding year than non-fatigued subjects while those with insufficient fatigue (ISF) were nearly 3 times more likely.Three domains emerged from text analysis on barriers to healthcare utilization: 1) accessibility; 2) knowledge-attitudes-beliefs (KABs); and, 3) healthcare system. CFS and reported duration of fatigue were significantly associated with each of these domains. Persons with CFS reported high levels of healthcare utilization barriers for each domain: accessibility (34%), healthcare system (25%), and KABs (19%). In further examination of barrier domains to healthcare utilization, compared to non-fatigued persons adjusted ORs for CFS having "accessibility", "KAB" and "Healthcare System" barrier domains decreased by 40%, 30%, and 19%, respectively. CONCLUSION: Barriers to healthcare utilization pose a significant problem in persons with fatiguing illnesses. Study results suggested two-fold implications: a symptom-targeted model focusing on symptoms associated with fatigue; and an interactive model requiring efforts from patients and providers to improve interactions between them by reducing barriers in accessibility, KABs, and healthcare system.

Web usage data as a means of evaluating public health messaging and outreach.

BACKGROUND: The Internet is increasingly utilized by researchers, health care providers, and the public to seek medical information. The Internet also provides a powerful tool for public health messaging. Understanding the needs of the intended audience and how they use websites is critical for website developers to provide better services to the intended users. OBJECTIVE: The aim of the study was to examine the utilization of the chronic fatigue syndrome (CFS) website at the Centers for Disease Control and Prevention (CDC). We evaluated (1) CFS website utilization, (2) outcomes of a CDC CFS public awareness campaign, and (3) user behavior related to public awareness campaign materials and CFS continuing medical education courses. METHODS: To describe and evaluate Web utilization, we collected Web usage data over an 18-month period and extracted page views, visits, referring domains, and geographic locations. We used page views as the primary measure for the CFS awareness outreach effort. We utilized market basket analysis and Markov chain model techniques to describe user behavior related to utilization of campaign materials and continuing medical education courses. RESULTS: The CDC CFS website received 3,647,736 views from more than 50 countries over the 18-month period and was the 33rd most popular CDC website. States with formal CFS programs had higher visiting density, such as Washington, DC; Georgia; and New Jersey. Most visits (71%) were from Web search engines, with 16% from non-search-engine sites and 12% from visitors who had bookmarked the site. The public awareness campaign was associated with a sharp increase and subsequent quick drop in Web traffic. Following the campaign, user interest shifted from information targeting consumer basic knowledge to information for health care professionals. The market basket analysis showed that visitors preferred the 60-second radio clip public service announcement over the 30-second one. Markov chain model results revealed that most visitors took the online continuing education courses in sequential order and were less likely to drop out after they reached the Introduction pages of the courses. CONCLUSIONS: The utilization of the CFS website reflects a high level of interest in the illness by visitors to the site. The high utilization shows the website to be an important online resource for people seeking basic information about CFS and for those looking for professional health care and research information. Public health programs should consider analytic methods to further public health by understanding the characteristics of those seeking information and by evaluating the outcomes of public health campaigns. The website was an effective means to provide health information about CFS and serves as an important public health tool for community outreach.

Continuing medical education challenges in chronic fatigue syndrome.

BACKGROUND: Chronic fatigue syndrome (CFS) affects at least 4 million people in the United States, yet only 16% of people with CFS have received a diagnosis or medical care for their illness. Educating health care professionals about the diagnosis and management of CFS may help to reduce population morbidity associated with CFS. METHODS: This report presents findings over a 5-year period from May 2000 to June 2006 during which we developed and implemented a health care professional educational program. The objective of the program was to distribute CFS continuing education materials to providers at professional conferences, offer online continuing education credits in different formats (e.g., print, video, and online), and evaluate the number of accreditation certificates awarded. RESULTS: We found that smaller conference size (OR = 80.17; 95% CI 8.80, 730.25), CFS illness related target audiences (OR = 36.0; 95% CI 2.94, 436.34), and conferences in which CFS research was highlighted (OR = 4.15; 95% CI 1.16, 14.83) significantly contributed to higher dissemination levels, as measured by visit rates to the education booth. While print and online courses were equally requested for continuing education credit opportunities, the online course resulted in 84% of the overall award certificates, compared to 14% for the print course. This remained consistent across all provider occupations: physicians, nurses, physician assistants, and allied health professionals. CONCLUSION: These findings suggest that educational programs promoting materials at conferences may increase dissemination efforts by targeting audiences, examining conference characteristics, and promoting online continuing education forums.