Research update: The relation between ME/CFS disease burden and research funding in the USA.

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a debilitating, chronic, multisystem disease that affects an estimated 1 to 2.5 million Americans. It has no widely accepted biomarkers and no FDA-approved treatment. ME/CFS has traditionally been one of the lowest funded diseases by the United States National Institutes of Health (NIH). OBJECTIVES: We provide here an update to our 2016 article, which estimated the disease burden of ME/CFS in the United States in 2013 and its relation to NIH's 2015 analysis of research funding and disease burden. This update incorporates more recent burden data from 2015 and funding data from 2017. METHODS: We perform a regression analysis on funding versus disease burden to determine 2017 funding levels that would be commensurate with burden. Burden figures for 2017 are estimated using population-based extrapolations of earlier data. RESULTS: We find the disease burden of ME/CFS is double that of HIV/AIDS and over half that of breast cancer. We also find that ME/CFS is more underfunded with respect to burden than any disease in NIH's analysis of funding and disease burden, with ME/CFS receiving roughly 7% of that commensurate with disease burden. CONCLUSIONS: To be commensurate with disease burden, NIH funding would need to increase roughly 14-fold.

Trends in the incidence of chronic fatigue syndrome and fibromyalgia in the UK, 2001-2013: a Clinical Practice Research Datalink study.

Objective Trends in recorded diagnoses of chronic fatigue syndrome (CFS, also known as 'myalgic encephalomyelitis' (ME)) and fibromyalgia (FM) in the UK were last reported more than ten years ago, for the period 1990-2001. Our aim was to analyse trends in incident diagnoses of CFS/ME and FM for the period 2001-2013, and to investigate whether incidence might vary by index of multiple deprivation (IMD) score. Design Electronic health records cohort study. Setting NHS primary care practices in the UK. Participants Participants: Patients registered with general practices linked to the Clinical Practice Research Datalink (CPRD) primary care database from January 2001 to December 2013. Main outcome measure Incidence of CFS/ME, FM, post-viral fatigue syndrome (PVFS), and asthenia/debility. Results The overall annual incidence of recorded cases of CFS/ME was 14.8 (95% CI 14.5, 15.1) per 100,000 people. Overall annual incidence per 100,000 people for FM was 33.3 (32.8-33.8), for PVFS 12.2 (11.9, 12.5), and for asthenia/debility 7.0 (6.8, 7.2). Annual incidence rates for CFS/ME diagnoses decreased from 17.5 (16.1, 18.9) in 2001 to 12.6 (11.5, 13.8) in 2013 (annual percent change -2.8% (-3.6%, -2.0%)). Annual incidence rates for FM diagnoses decreased from 32.3 (30.4, 34.3) to 27.1 (25.5, 28.6) in 2007, then increased to 38.2 (36.3, 40.1) per 100,000 people in 2013. Overall annual incidence of recorded fatigue symptoms was 2246 (2242, 2250) per 100,000 people. Compared with the least deprived IMD quintile, incidence of CFS/ME in the most deprived quintile was 39% lower (incidence rate ratio (IRR) 0.61 (0.50, 0.75)), whereas rates of FM were 40% higher (IRR 1.40 (0.95, 2.06)). Conclusion These analyses suggest a gradual decline in recorded diagnoses of CFS/ME since 2001, and an increase in diagnoses of fibromyalgia, with opposing socioeconomic patterns of lower rates of CFS/ME diagnoses in the poorest areas compared with higher rates of FM diagnoses.

Investigating unexplained fatigue in general practice with a particular focus on CFS/ME.

Unexplained fatigue is not infrequent in the community. It presents a number of challenges to the primary care physician and particularly if the clinical examination and routine investigations are normal. However, while fatigue is a feature of many common illnesses, it is the main problem in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). This is a poorly understood condition that is accompanied by several additional symptoms which suggest a subtle multisystem dysfunction. Not infrequently it is complicated by sleep disturbance and alterations in attention, memory and mood.Specialised services for the diagnosis and management of CFS/ME are markedly deficient in the UK and indeed in virtually all countries around the world. However, unexplained fatigue and CFS/ME may be confidently diagnosed on the basis of specific clinical criteria combined with the normality of routine blood tests. The latter include those that assess inflammation, autoimmunity, endocrine dysfunction and gluten sensitivity. Early diagnosis and intervention in general practice will do much to reduce patient anxiety, encourage improvement and prevent expensive unnecessary investigations.There is presently an on-going debate as to the precise criteria that best confirms CFS/ME to the exclusion of other medical and psychiatric/psychological causes of chronic fatigue. There is also some disagreement as to best means of investigating and managing this very challenging condition. Uncertainty here can contribute to patient stress which in some individuals can perpetuate and aggravate symptoms. A simple clinical scoring system and a short list of routine investigations should help discriminate CFS/ME from other causes of continued fatigue.

Housebound versus nonhousebound patients with myalgic encephalomyelitis and chronic fatigue syndrome.

OBJECTIVES: The objective of this study was to examine individuals with myalgic encephalomyelitis and chronic fatigue syndrome who are confined to their homes due to severe symptomatology. The existing literature fails to address differences between this group, and less severe, nonhousebound patient populations. METHODS: Participants completed the DePaul Symptom Questionnaire, a measure of myalgic encephalomyelitis and chronic fatigue syndrome symptomology, and the SF-36, a measure of health impact on physical/mental functioning. ANOVAs and, where appropriate, MANCOVAS were used to compare housebound and nonhousebound patients with myalgic encephalomyelitis and chronic fatigue syndrome across areas of functioning, symptomatology, and illness onset characteristics. RESULTS: Findings indicated that the housebound group represented one quarter of the sample, and were significantly more impaired with regards to physical functioning, bodily pain, vitality, social functioning, fatigue, postexertional malaise, sleep, pain, neurocognitive, autonomic, neuroendocrine, and immune functioning compared to individuals who were not housebound. DISCUSSION: Findings indicated that housebound patients have more impairment on functional and symptom outcomes compared to those who were not housebound. Understanding the differences between housebound and not housebound groups holds implications for physicians and researchers as they develop interventions intended for patients who are most severely affected by this chronic illness.

Attention network test: assessment of cognitive function in chronic fatigue syndrome.

Information processing difficulties are common in patients with chronic fatigue syndrome (CFS). It has been shown that the time it takes to process a complex cognitive task, rather than error rate, may be the critical variable underlying CFS patients' cognitive complaints. The Attention Network Task (ANT) developed by Fan and colleagues may be of clinical utility to assess cognitive function in CFS, because it allows for simultaneous assessment of mental response speed, also called information processing speed, and error rate under three conditions challenging the attention system. Comparison of data from two groups of CFS patients (those with and without comorbid major depressive disorder; n = 19 and 22, respectively) to controls (n = 29) consistently showed that error rates did not differ among groups across conditions, but speed of information processing did. Processing time was prolonged in both CFS groups and most significantly affected in response to the most complex task conditions. For simpler tasks, processing time was only prolonged in CFS participants with depression. The data suggest that the ANT may be a task that could be used clinically to assess information processing deficits in individuals with CFS.

The effect of counselling, graded exercise and usual care for people with chronic fatigue in primary care: a randomized trial.

BACKGROUND: To evaluate the effectiveness of graded exercise therapy (GET), counselling (COUNS) and usual care plus a cognitive behaviour therapy (CBT) booklet (BUC) for people presenting with chronic fatigue in primary care. METHOD: A randomized controlled trial in general practice. The main outcome measure was the change in the Chalder fatigue score between baseline and 6 months. Secondary outcomes included a measure of global outcome, including anxiety and depression, functional impairment and satisfaction. RESULTS: The reduction in mean Chalder fatigue score at 6 months was 8.1 [95% confidence interval (CI) 6.6-10.4] for BUC, 10.1 (95% CI 7.5-12.6) for GET and 8.6 (95% CI 6.5-10.8) for COUNS. There were no significant differences in change scores between the three groups at the 6- or 12-month assessment. Dissatisfaction with care was high. In relation to the BUC group, the odds of dissatisfaction at the 12-month assessment were less for the GET [odds ratio (OR) 0.11, 95% CI 0.02-0.54, p=0.01] and COUNS groups (OR 0.13, 95% CI 0.03-0.53, p=0.004). CONCLUSIONS: Our evidence suggests that fatigue presented to general practitioners (GPs) tends to remit over 6 months to a greater extent than found previously. Compared to BUC, those treated with graded exercise or counselling therapies were not significantly better with respect to the primary fatigue outcome, although they were less dissatisfied at 1 year. This evidence is generalizable nationally and internationally. We suggest that GPs ask patients to return at 6 months if their fatigue does not remit, when therapy options can be discussed further.

Psychometric characteristics of the short form 36 health survey and functional assessment of chronic illness Therapy-Fatigue subscale for patients with ankylosing spondylitis.

BACKGROUND: We evaluated the psychometric characteristics of the Short Form 36 (SF-36) Health Survey and the Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue subscale in patients with ankylosing spondylitis (AS). METHODS: We analyzed clinical and patient-reported outcome (PRO) data collected during 12-week, double-blind, placebo-controlled periods of two randomized controlled trials comparing adalimumab and placebo for the treatment of active AS. The Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, and other clinical measures were collected during the clinical trial. We evaluated internal consistency/reliability, construct validity, and responsiveness to change for the SF-36 and FACIT-Fatigue. RESULTS: The SF-36 (Cronbach alpha, 0.74-0.92) and FACIT-Fatigue (Cronbach alpha, 0.82-0.86) both had good internal consistency/reliability. At baseline, SF-36 and FACIT-Fatigue scores correlated significantly with Ankylosing Spondylitis Quality of Life scores (r = -0.36 to -0.66 and r = -0.70, respectively; all p < 0.0001). SF-36 scores varied by indicators of clinical severity, with greater impairment observed for more severe degrees of clinical activity (all p < 0.0001). FACIT-Fatigue scores correlated significantly with SF-36 scores (r = 0.42 to 0.74; all p < 0.0001) and varied by clinical severity (p < 0.05 to p < 0.0001). CONCLUSIONS: The SF-36 is a reliable, valid, and responsive measure of health-related quality of life and the FACIT-Fatigue is a brief and psychometrically sound measure of the effects of fatigue on patients with AS. These PROs may be useful in evaluating effectiveness of new treatments for AS.

Evaluation of health-related quality of life, fatigue and depression in neuromyelitis optica.

BACKGROUND: The burden of multiple sclerosis (MS) includes fatigue, depression and worsening of health-related quality of life (HRQOL). These changes have not been yet measured in neuromyelitis optica (NMO). Our aim was to assess the HRQOL, fatigue and depression in NMO. METHODS: We administered French validated self-questionnaires on HRQOL (SEP-59), fatigue (EMIF-SEP) and depression (EHD) to 40 patients followed up in two centres. We assessed the relationship of these parameters with gender, age, disability, disease duration, visual acuity and NMO-antibody status and also compared our results with equivalent data in MS and normal subjects derived from previous studies. RESULTS: Health-related quality of life scores were lower (P < 0.01) in patients with NMO when compared to normal subjects. No significant difference was noted between patients with NMO and MS for most scores, the exceptions being HRQOL related to cognitive function (better in NMO than in MS), HRQOL related to sphincter dysfunction (worse in NMO than in MS) and the psychological dimension of fatigue (milder in NMO than in MS). Disability was the main predictive factor of an unfavourable evolution. DISCUSSION: This study reveals the strong impact of NMO on HRQOL, fatigue and depression and the importance of screening patients, especially the more disabled, so as to initiate suitable treatment.

An assessment of prospective memory retrieval in women with chronic fatigue syndrome using a virtual-reality environment: an initial study.

People with chronic fatigue syndrome (CFS) have increased rates of depression, anxiety, and illness intrusiveness; they may also suffer from cognitive problems such as retrospective memory (RM) deficits and concentration difficulties that can stem from diminished information-processing capability. We predicted that this diminished capacity may also lead to deficits in other cognitive functions, such as prospective memory (ProM). Event-, time-, and activity-based ProM was assessed in 11 women with CFS and 12 healthy women using a computer-generated virtual environment (VE). RM was assessed using a free-recall test, and subjective assessment of both ProM and RM was assessed by questionnaire. Groups were equivalent in age and measures of IQ. People with CFS performed slightly worse than healthy controls on both the event- and time-based ProM measures, although these were not statistically significant. However, the CFS group performed significantly worse than the healthy controls on both the free recall-task and on subjective assessment of both RM and ProM. Women with CFS do have some subtle decrements in memory, particularly RM. However, it is possible that the decrements found in the present sample would be greater in real life. Further studies utilizing both healthy controls and illness controls are now needed to ascertain how sensitive the VE measure is and to inform the development of tasks in the VE that place progressively increasing demands on working memory capacity.

Assessment of fibromyalgia & chronic fatigue syndrome: a new protocol designed to determine work capability--chronic pain abilities determination (CPAD).

The objective was to design a protocol to assess work ability in people suffering ill-defined painful and disabling disorders, the outstanding prototype of which is fibromyalgia/chronic fatigue syndrome (FM/CSF).Following an extensive literature search, the mos appropriate components of current methods of assessment of physical and cognitive abilities were incorporated into the protocol, occasionally with appropriate modification to suit the specific requirements of the individual. The initial part of the assessment consists of a standard history taking, principally focusing on the patient's self-reported physical and cognitive abilities and disabilities, as well as the completion of established pain and fatigue scales, and relevant disability questionnaires. Following this, physical and cognitive abilities are objectively assessed on two separate occasions, utilizing computerized hand-held dynamometers, inclinometers, algometers, and force dynamometers. Specific work simulation tests using the industrial standards Methods-Time-Measurement testing are availed of, as is aerobic testing using the Canadian Aerobic Fitness Test (CAFT). Objective computerised neuro-cognitive testing are also utilised as an integral component of the assessment. All results are then subject to specific computerized analysis and compared to normative and standardised work-based databases. The designed system produces reliable, consistent and reproducible results. It also proves capable of detecting any inconsistencies in patient input and results, in addition to being independent of any possible assessor bias. A new protocol has been designed to determine the working capability of individuals who suffer from various chronic disabling conditions, and represents a significant step forward in a difficult but rapidly expanding area of medical practice.

Actigraphic assessment of sleep disorders in children with chronic fatigue syndrome.

UNLABELLED: Children with chronic fatigue syndrome (CFS) often suffer from sleep disorders, which cause many physiological and psychological problems. Understanding sleep characteristics in children with CFS is important for establishing a therapeutic strategy. We conducted an actigraphic study to clarify the problems in sleep/wake rhythm and physical activity in children with CFS. METHODS: Actigraphic recordings were performed for 1-2 weeks in 12 CFS children. The obtained data were compared with those of healthy age-matched children used as the control. RESULTS: Sleep patterns were divided into two groups based on subjects' sleep logs: irregular sleep type and delayed sleep phase type. Compared to the control group, total sleep time was longer and physical activity was lower in both groups of CFS. Continuous sleep for more than 10h was not uncommon in CFS. In the irregular sleep type, impaired daily sleep/wake rhythms and disrupted sleep were observed. CONCLUSION: Using actigraphy, we could identify several characteristics of the sleep patterns in CFS children. Actigraphic analysis proved to be useful in detecting sleep/wake problems in children with CFS.

Objective assessment of personality disorder in chronic fatigue syndrome.

OBJECTIVES: This study aims to objectively assess the prevalence and nature of personality disorders in depressed and nondepressed chronic fatigue syndrome (CFS) patients and compare this to depressed and healthy control groups. METHODS: Sixty-one patients attending a tertiary referral clinic with chronic fatigue syndrome, 40 psychiatric inpatients with depressive disorder and 45 healthy medical students completed the Structured Clinical Interview for DSM-III-R Diagnoses (SCID-II) in addition to providing routine clinical and demographic information. RESULTS: Thirty-nine percent of the CFS group, 73% of the depressed group and 4% of the healthy group were diagnosed with personality disorders. Cluster C disorders were the most common in both the CFS and depressed group. The depressed CFS patients had more Cluster B personality disorders than nondepressed CFS patients. Overall for CFS patients there was no association between mood state and personality disorder. CONCLUSIONS: High levels of personality disorder are found on objective assessment of CFS patients attending a teaching hospital clinic. This cannot be accounted for by comorbid depression.

[Disability retirement pension for patients with syndrome diagnoses. A registry study on the basis of data from the Social Appeal Board]. / Førtidspension til patienter med syndromesygdomme. En registerundersøgelse på basis of oplysninger fra Den Sociale Ankestyrelse.

INTRODUCTION: Since the early 1990s, disability retirement pension may be granted on the basis of a syndrome diagnosis. Before the pension can be granted, local public authorities collect information on health and social matters and report to The Social Appeal Board. In 1998, a new diagnostic tool was introduced based on the International Statistical Classification of Diseases and Related Health Problems (ICD-10) diagnoses. The information available in The Social Appeal Board has made it possible to study the social consequences of a syndrome diagnosis. The purpose of the study was: 1) To estimate the incidence of patients granted disability retirement pension with the diagnoses whiplash, fibromyalgia, chronic pain disorder, chronic fatigue syndromee, chronic strain syndromee, and pelvic syndromee. 2) To estimate changes in the level of pension granted to patients with syndromee diagnosis. 3) To compare differences between patients with syndromee diagnosis granted disability retirement pension to patients with other diagnoses on the following parameters: sex, civil status, income when applying for pension, and attempts of rehabilitation. 4) To estimate comorbidity of psychiatric diagnosis in patients with syndromee diagnosis. MATERIAL AND METHODS: A register study of data on pension reported to The National Social Appeal Board in the period July 1st 1998 to December 31st, 2000. RESULTS: Of all patients granted pension in the period 8.3 per cent had a syndromee diagnosis, 11 per cent of the women and 5 per cent of the men. Both the relative and the absolute number of patients with syndromee diagnosis granted a pension were increasing. Comorbidity of psychiatric disorders was 3 per cent in the group with syndromee diagnosis. More patients with syndromee diagnosis than with other diagnoses had received sickness benefits and rehabilitation when pension was granted. DISCUSSION: The large number of patients with syndromee diagnosis granted pension calls for multidisciplinary prophylactic and treatment initiatives in order to reduce the number of patients in need of public support. The results are discussed in view of the new Pension's Act which will become effective as from January 1st, 2003.

Assessment of cardiovascular reactivity by fractal and recurrence quantification analysis of heart rate and pulse transit time.

Methods used for the assessment of cardiovascular reactivity are flawed by nonlinear dynamics of the cardiovascular responses to stimuli. In an attempt to address this issue, we utilized a short postural challenge, recorded beat-to-beat heart rate (HR) and pulse transit time (PTT), assessed the data by fractal and recurrence quantification analysis, and processed the obtained variables by multivariate statistics. A 10-min supine phase of the head-up tilt test was followed by recording 600 cardiac cycles on tilt, that is, 5-10 min. Three groups of patients were studied, each including 20 subjects matched for age and gender--healthy subjects, patients with essential hypertension (HT), and patients with chronic fatigue syndrome (CFS). The latter group was studied on account of the well-known dysautonomia of CFS patients, which served as contrast against the cardiovascular reactivity of the healthy population. A total of 52 variables of the HR and PTT were determined in each subject. The multivariate model identified the best predictors for the assessment of reactivity of healthy subjects vs CFS. Based on these predictors, the "Fractal & Recurrence Analysis-based Score" (FRAS) was calculated: FRAS=76.2+0.04*HR-supine-DET -12.9*HR-tilt-R/L -0.31*HR-tilt-s.d. -19.27*PTT-tilt-R/L -9.42*PTT-tilt-WAVE. The median values and IQR of FRAS in the groups were: healthy=-1.85 (IQR 1.89), hypertensives=+0.52 (IQR 5.78), and CFS=-24.2 (5.34) (HT vs healthy subjects: P=0.0036; HT vs CFS: P<0.0001). Since the FRAS differed significantly between the three groups, it appears likely that the FRAS may recognize phenotypes of cardiovascular reactivity.

Quantitative assessment of cerebral ventricular volumes in chronic fatigue syndrome.

Previous qualitative volumetric assessment of lateral ventricular enlargement in chronic fatigue syndrome (CFS) has provided evidence for subtle structural changes in the brains of some individuals with CFS. The aim of this pilot study was to determine whether a more sensitive quantitative assessment of the lateral ventricular system would support the previous qualitative findings. In this study, we compared the total lateral ventricular volume, as well as the right and left hemisphere subcomponents in 28 participants with CFS and 15 controls. Ventricular volumes in the CFS group were larger than in control groups, a difference that approached statistical significance. Group differences in ventricular asymmetry were not observed. The results of this study provide further evidence of subtle pathophysiological changes in the brains of participants with CFS.

Longitudinal assessment of neuropsychological functioning, psychiatric status, functional disability and employment status in chronic fatigue syndrome.

The longitudinal course of subjective and objective neuropsychological functioning, psychological functioning, disability level, and employment status in chronic fatigue syndrome (CFS) was examined. The relations among several key outcomes at follow-up, as well as the baseline characteristics that predict change (e.g., improvement), were also evaluated. The study sample consisted of 35 individuals who met the 1988 and 1994 CFS case definition criteria of the Centers for Disease Control (CDC) at intake. Participants were evaluated a mean of 41.9 (SEM = 1.7) months following their initial visit (range = 24-63 months). Results indicated that objective and subjective attention abilities, mood, level of fatigue, and disability improve over time in individuals with CFS. Moreover, improvements in these areas were found to be interrelated at follow-up. Finally, psychiatric status, age, and between-test duration were significant predictors of outcome. Overall, the prognosis for CFS appears to be poor, as the majority of participants remained functionally impaired over time and were unemployed at follow-up, despite the noted improvements.

Assessment of depression in patients with chronic fatigue syndrome.

Assessment of the relationship of depression to chronic fatigue syndrome (CFS) is a complicated but important topic. This relationship may range from the misdiagnostic (i.e., depression misidentified as CFS) to the etiologic (i.e., CFS causes an organic affective syndrome). Assessment should focus on the symptoms and syndromes of depressive disorder, utilization of a single rating scale to assess presumed depression is discouraged, and alternate approaches to classification that allow for symptomatic overlap of a major depressive disorder and CFS are suggested. Careful attention needs to be given to the use of external validating criteria in empiric studies, such as natural history, clinical course (including treatment response), and family history.

Testing of vestibular function: an adjunct in the assessment of chronic fatigue syndrome.

Patients with chronic fatigue syndrome (CFS) often complain of dysequilibrium that is nonspecific. The basis of this complaint is unknown but may be related to vestibular system abnormalities, in that an association between inner-ear deficits and infectious mononucleosis has been established in the medical literature. An overview of quantitative vestibular function testing is given, including vestibulo-ocular and vestibulospinal tests. The basic principles of caloric and rotational testing are provided, including the interaction between vision and the vestibular system. Moving-platform posturography is described. Preliminary results from quantitative vestibular function testing of a small group of individuals with CFS are provided.

Methodologic considerations in assessment of cognitive function in chronic fatigue syndrome.

Rigorous and standardized assessment of cognitive function is an important component of any multidisciplinary study of chronic fatigue syndrome. The present paper describes some methodologic issues that need to be addressed to maximize the yield from any neuropsychiatric evaluation of the syndrome.