Gene Expression Factor Analysis to Differentiate Pathways Linked to Fibromyalgia, Chronic Fatigue Syndrome, and Depression in a Diverse Patient Sample

Abstract:

OBJECTIVE: To determine if independent candidate genes can be grouped into meaningful biologic factors, and whether these factors are associated with the diagnosis of chronic fatigue syndrome (CFS) and fibromyalgia syndrome (FMS), while controlling for comorbid depression, sex, and age.

METHODS: We included leukocyte messenger RNA gene expression from a total of 261 individuals, including healthy controls (n = 61), patients with FMS only (n = 15), with CFS only (n = 33), with comorbid CFS and FMS (n = 79), and with medication-resistant (n = 42) or medication-responsive (n = 31) depression. We used exploratory factor analysis (EFA) on 34 candidate genes to determine factor scores and regression analysis to examine whether these factors were associated with specific diagnoses.

RESULTS: EFA resulted in 4 independent factors with minimal overlap of genes between factors, explaining 51% of the variance. We labeled these factors by function as 1) purinergic and cellular modulators, 2) neuronal growth and immune function, 3) nociception and stress mediators, and 4) energy and mitochondrial function. Regression analysis predicting these biologic factors using FMS, CFS, depression severity, age, and sex revealed that greater expression in factors 1 and 3 was positively associated with CFS and negatively associated with depression severity (Quick Inventory for Depression Symptomatology score), but not associated with FMS.

CONCLUSION: Expression of candidate genes can be grouped into meaningful clusters, and CFS and depression are associated with the same 2 clusters, but in opposite directions, when controlling for comorbid FMS. Given high comorbid disease and interrelationships between biomarkers, EFA may help determine patient subgroups in this population based on gene expression.

© 2016, American College of Rheumatology.

 

Source: Iacob E, Light AR, Donaldson GW, Okifuji A, Hughen RW, White AT, Light KC. Gene Expression Factor Analysis to Differentiate Pathways Linked to Fibromyalgia, Chronic Fatigue Syndrome, and Depression in a Diverse Patient Sample. Arthritis Care Res (Hoboken). 2016 Jan;68(1):132-40. doi: 10.1002/acr.22639. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4684820/ (Full article)

 

Chronic fatigue syndrome and fibromyalgia in Canada: prevalence and associations with six health status indicators

Abstract:

INTRODUCTION: Few studies have considered the factors independently associated with chronic fatigue syndrome (CFS) and/or fibromyalgia (FM) or considered the impact of these conditions on health status using population-based data.

METHODS: We used data from the nationally representative 2010 Canadian Community Health Survey (n = 59 101) to describe self-reported health professional-diagnosed CFS and/or FM, and their associations with 6 health status indicators.

RESULTS: In 2010, diagnosed CFS and FM are reported by 1.4% (95% confidence interval [CI]: 1.3%-1.6%) and 1.5% (1.4%-1.7%), respectively, of the Canadian household population aged 12 years and over, with comorbid CFS and FM affecting 0.3% (0.3%-0.4%) of that population. Prevalent CFS and/or FM were more common among women, adults aged 40 years and over, those with lowest income, and those with certain risk factors for chronic disease (i.e. obesity, physical inactivity and smoking). After controlling for differences between the groups, people with CFS and/or FM reported poorer health status than those with neither condition on 5 indicators of health status, but not on the measure of fair/poor mental health. Having both CFS and FM and having multiple comorbid conditions was associated with poorer health status.

CONCLUSION: Co-occurrence of CFS and FM and having other chronic conditions were strongly related to poorer health status and accounted for much of the differences in health status. Understanding factors contributing to improved quality of life in people with CFS and/or FM, particularly in those with both conditions and other comorbidities, may be an important area for future research.

 

Source: Rusu C, Gee ME, Lagacé C, Parlor M. Chronic fatigue syndrome and fibromyalgia in Canada: prevalence and associations with six health status indicators. Health Promot Chronic Dis Prev Can. 2015 Mar;35(1):3-11. [Article in English, French; Abstract available in French from the publisher] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4939456/ (Full article)

 

Chronic fatigue syndrome and non-celiac gluten sensitivity. Association or cause?

To the editor:

In their letter to the editor Response to: Fibromyalgia and chronic fatigue caused by non-celiac gluten sensitivity, Qanneta et al. pose a conceptual problem between the association of chronic fatigue syndrome (CFS) with non-celiac gluten sensitivity (SGNC) from the prevalent conception of considering chronic fatigue as a distinct disease. From this perspective, being chronic fatigue the central disease associated with other processes, they consider NCGS as a comorbid condition and not as an underlying cause.

You can read the rest of this letter here: http://www.reumatologiaclinica.org/en/chronic-fatigue-syndrome-non-celiac-gluten/articulo/S2173574314001762/

Comment on

 

Source: Isasi Zaragozá C. Chronic fatigue syndrome and non-celiac gluten sensitivity. Association or cause?Reumatol Clin. 2015 May-Jun;11(3):184. doi: 10.1016/j.reuma.2014.10.010. Epub 2014 Dec 10. http://www.reumatologiaclinica.org/en/chronic-fatigue-syndrome-non-celiac-gluten/articulo/S2173574314001762/ (Full article)

 

Response to: fibromyalgia and chronic fatigue syndrome caused by non-celiac gluten sensitivity

Dear Editor:

We have closely read the article published by Isasi et al.1 in Reumatologia Clínica presenting a case of fibromyalgia (FM) and chronic fatigue syndrome (CFS) caused by non-celiac sensitivity to gluten (NGCD). We would like to comment our experience with this attractive topic regarding patients with FM/CFS, which I hope will contribute to an improved knowledge of this association. The authors have reasonably ruled out celiac disease (CD) and have hypothesized that NGCD is the cause of FM and CFS in their patient; upon complete remission (CR) of symptoms, both digestive and musculoskeletal, with a gluten-free diet (GFD).

You can read the rest of this letter here: http://www.reumatologiaclinica.org/en/response-to-fibromyalgia-chronic-fatigue/articulo/S217357431400166X/

 

Source: Qanneta R, Fontova R, Castel A. Response to: fibromyalgia and chronic fatigue syndrome caused by non-celiac gluten sensitivity. Reumatol Clin. 2015 May-Jun;11(3):185. doi: 10.1016/j.reuma.2014.09.008. Epub 2014 Nov 7. http://www.reumatologiaclinica.org/en/response-to-fibromyalgia-chronic-fatigue/articulo/S217357431400166X/ (Full article)

What is in a name? Comparing diagnostic criteria for chronic fatigue syndrome with or without fibromyalgia

Abstract:

The current study had two objectives. (1) to compare objective and self-report measures in patients with chronic fatigue syndrome (CFS) according to the 1994 Center for Disease Control (CDC) criteria, patients with multiple sclerosis (MS), and healthy controls, and (2) to contrast CFS patients who only fulfill CDC criteria to those who also fulfill the criteria for myalgic encephalomyelitis (ME), the 2003 Canadian criteria for ME/CFS, or the comorbid diagnosis of fibromyalgia (FM).

One hundred six participants (48 CFS patients diagnosed following the 1994 CDC criteria, 19 MS patients, and 39 healthy controls) completed questionnaires assessing symptom severity, quality of life, daily functioning, and psychological factors. Objective measures consisted of activity monitoring, evaluation of maximal voluntary contraction and muscle recovery, and cognitive performance. CFS patients were screened whether they also fulfilled ME criteria, the Canadian criteria, and the diagnosis of FM.

CFS patients scored higher on symptom severity, lower on quality of life, and higher on depression and kinesiophobia and worse on MVC, muscle recovery, and cognitive performance compared to the MS patients and the healthy subjects. Daily activity levels were also lower compared to healthy subjects. Only one difference was found between those fulfilling the ME criteria and those who did not regarding the degree of kinesiophobia (lower in ME), while comorbidity for FM significantly increased the symptom burden.

CFS patients report more severe symptoms and are more disabled compared to MS patients and healthy controls. Based on the present study, fulfillment of the ME or Canadian criteria did not seem to give a clinically different picture, whereas a diagnosis of comorbid FM selected symptomatically worse and more disabled patients.

 

Source: Meeus M, Ickmans K, Struyf F, Kos D, Lambrecht L, Willekens B, Cras P, Nijs J. What is in a name? Comparing diagnostic criteria for chronic fatigue syndrome with or without fibromyalgia. Clin Rheumatol. 2016 Jan;35(1):191-203. doi: 10.1007/s10067-014-2793-x. Epub 2014 Oct 14. https://www.ncbi.nlm.nih.gov/pubmed/25308475

 

Multiple Sclerosis/Chronic Fatigue Syndrome overlap: When two common disorders collide

Abstract:

INTRODUCTION: Fatigue is a major cause of disability and handicap in Multiple Sclerosis (MS) patients. The management of this common problem is often difficult. Chronic Fatigue Syndrome (CFS/ME) is another common cause of fatigue which is prevalent in the same population of middle aged females commonly affected by MS.

AIM: This report aims at examining the potential coexistence of MS and CFS/ME in the same patients.

METHOD: This is a retrospective study examining a cohort of MS patients referred for rehabilitation. The subjects were screened for CFS/ME symptoms.

RESULTS: Sixty-four MS patients (43 females) were screened for CFS/ME. Nine patients (14%) with a mean age 52 (SD 9.7) who were all females fulfilled the Fukuda criteria for diagnosis of CFS/ME. Their symptoms, including muscular and joint pain, malaise and recurrent headaches, were not explained by the pattern of their MS.

DISCUSSION: MS and CFS/ME are two common conditions with increased prevalence in middle aged females. As the diagnosis of CFS/ME is clinical with no positive clinical signs or investigations; it can be made with difficulty in the presence of another clear explanation for the disabling fatigue. Our results suggest that the two conditions may co-exist. Considering CFS/ME as a potential co-morbidity may lead to more focused and appropriate management.

 

Source: Gaber TA, Oo WW, Ringrose H. Multiple Sclerosis/Chronic Fatigue Syndrome overlap: When two common disorders collide. NeuroRehabilitation. 2014;35(3):529-34. doi: 10.3233/NRE-141146. https://www.ncbi.nlm.nih.gov/pubmed/25238862

 

Endogenous pain modulation in response to exercise in patients with rheumatoid arthritis, patients with chronic fatigue syndrome and comorbid fibromyalgia, and healthy controls: a double-blind randomized controlled trial

Abstract:

OBJECTIVE: Temporal summation (TS) of pain, conditioned pain modulation (CPM), and exercise-induced analgesia (EIA) are often investigated in chronic pain populations as an indicator for enhanced pain facilitation and impaired endogenous pain inhibition, respectively, but interactions are not yet clear both in healthy controls and in chronic pain patients. Therefore, the present double-blind randomized placebo-controlled study evaluates pains cores, TS, and CPM in response to exercise in healthy controls, patients with chronic fatigue syndrome and comorbid fibromyalgia (CFS/FM), and patients with rheumatoid arthritis (RA), both under placebo and paracetamol condition.

METHODS: Fifty-three female volunteers – of which 19 patients with CFS/FM, 16 patients with RA, and 18 healthy controls – underwent a submaximal exercise test on a bicycle ergometer on 2 different occasions (paracetamol vs. placebo), with an interval of 7 days. Before and after exercise, participants rated pain intensity during TS and CPM.

RESULTS: Patients with rheumatoid arthritis showed decreased TS after exercise, both after paracetamol and placebo (P < 0.05). In patients with CFS/FM, results were less univocal. A nonsignificant decrease in TS was only observed after taking paracetamol. CPM responses to exercise are inconclusive, but seem to worsen after exercise. No adverse effects were seen.

CONCLUSION: This study evaluates pain scores, TS, and CPM in response to submaximal exercise in 2 different chronic pain populations and healthy controls. In patients with RA, exercise had positive effects on TS, suggesting normal EIA. In patients with CFS/FM, these positive effects were only observed after paracetamol and results were inconsistent.

TRIAL REGISTRATION: ClinicalTrials.gov NCT01154647.

 

Source: Meeus M, Hermans L, Ickmans K, Struyf F, Van Cauwenbergh D, Bronckaerts L, De Clerck LS, Moorken G, Hans G, Grosemans S, Nijs J. Endogenous pain modulation in response to exercise in patients with rheumatoid arthritis, patients with chronic fatigue syndrome and comorbid fibromyalgia, and healthy controls: a double-blind randomized controlled trial. Pain Pract. 2015 Feb;15(2):98-106. doi: 10.1111/papr.12181. Epub 2014 Feb 17. https://www.ncbi.nlm.nih.gov/pubmed/24528544

 

Comorbidity of postural orthostatic tachycardia syndrome and chronic fatigue syndrome in an Australian cohort

Abstract:

OBJECTIVE: Patients with chronic fatigue syndrome (CFS) are frequently diagnosed with comorbid postural orthostatic tachycardia syndrome (POTS), suggesting a shared pathogenesis. The aim of this study was to examine the relationship between demographic characteristics, autonomic functioning and fatigue levels amongst CFS patients with and without comorbid POTS.

DESIGN AND SETTING: All patients presenting to the CFS Discovery Clinic between 2009 and 2012 completed a 20-min standing task as part of their initial assessment. Heart rate and pulse pressure were recorded at baseline, at 2-min intervals poststanding, at the end of the task and following a recovery period. Average heart rate and pulse pressure variability were calculated from this data. Age, gender, length of illness and self-reported fatigue scores were also recorded. POTS patients were diagnosed by an orthostatic increase in heart rate >30 beats per min, concomitant symptoms of orthostatic intolerance and no orthostatic hypotension. Differences in autonomic functioning between POTS and CFS patients were compared using independent samples t-tests, whilst logistic and linear regressions were performed to examine the contribution of autonomic functioning to task completion and perceived fatigue, respectively.

RESULTS:Comorbidity of CFS and POTS (CFS-POTS) was observed in 11% (33/306) of patients. CFS-POTS patients were significantly younger (P < 0.001), had a shorter length of illness (P = 0.034), experienced greater task difficulty (P = 0.002) and were able to stand for significantly shorter periods compared to the CFS-only patients (P < 0.001). CFS-POTS patients experienced significantly lower baseline diastolic blood pressure (P = 0.002), significantly higher heart rate and lower pulse pressures at each standing measurement. Early heart rate changes (P = 0.002) and overall heart rate change (P < 0.001) were significant predictors of completion status, whereas heart rate variability (P < 0.001) and female gender (P < 0.001) were significant predictors of increased perceived task difficulty.

CONCLUSIONS:Haemodynamic and demographic differences between CFS-POTS and CFS-only patients suggest that the former group reflects a distinct subgroup of the CFS population. The findings highlight the utility of screening younger patients with fatigue for POTS, and identified heart rate variability as an important marker of fatigue for CFS patients in general.

© 2013 The Association for the Publication of the Journal of Internal Medicine.

 

Source: Reynolds GK, Lewis DP, Richardson AM, Lidbury BA. Comorbidity of postural orthostatic tachycardia syndrome and chronic fatigue syndrome in an Australian cohort. J Intern Med. 2014 Apr;275(4):409-17. doi: 10.1111/joim.12161. Epub 2013 Nov 29. http://onlinelibrary.wiley.com/doi/10.1111/joim.12161/full (Full article)

 

Undiagnosed and comorbid disorders in patients with presumed chronic fatigue syndrome

Abstract:

OBJECTIVE: To assess undiagnosed and comorbid disorders in patients referred to a tertiary care center with a presumed diagnosis of chronic fatigue syndrome (CFS).

METHODS: Patients referred for chronic unexplained fatigue entered an integrated diagnostic pathway, including internal medicine assessment, psychodiagnostic screening, physiotherapeutic assessment and polysomnography+multiple sleep latency testing. Final diagnosis resulted from a multidisciplinary team discussion. Fukuda criteria were used for the diagnosis of CFS, DSM-IV-TR criteria for psychiatric disorders, ICSD-2 criteria for sleep disorders.

RESULTS: Out of 377 patients referred, 279 (74.0%) were included in the study [84.9% female; mean age 38.8years (SD 10.3)]. A diagnosis of unequivocal CFS was made in 23.3%. In 21.1%, CFS was associated with a sleep disorder and/or psychiatric disorder, not invalidating the diagnosis of CFS. A predominant sleep disorder was found in 9.7%, 19.0% had a psychiatric disorder and 20.8% a combination of both. Only 2.2% was diagnosed with a classical internal disease. In the total sample, a sleep disorder was found in 49.8%, especially obstructive sleep apnea syndrome, followed by psychophysiologic insomnia and periodic limb movement disorder. A psychiatric disorder was diagnosed in 45.2%; mostly mood and anxiety disorder.

CONCLUSIONS: A multidisciplinary approach to presumed CFS yields unequivocal CFS in only a minority of patients, and reveals a broad spectrum of exclusionary or comorbid conditions within the domains of sleep medicine and psychiatry. These findings favor a systematic diagnostic approach to CFS, suitable to identify a wide range of diagnostic categories that may be subject to dedicated care.

© 2013. Published by Elsevier Inc. All rights reserved.

 

Source: Mariman A, Delesie L, Tobback E, Hanoulle I, Sermijn E, Vermeir P, Pevernagie D, Vogelaers D. Undiagnosed and comorbid disorders in patients with presumed chronic fatigue syndrome. J Psychosom Res. 2013 Nov;75(5):491-6. doi: 10.1016/j.jpsychores.2013.07.010. Epub 2013 Aug 20. https://www.ncbi.nlm.nih.gov/pubmed/24182640

 

Examining the impact of obesity on individuals with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a complex disorder affecting multiple body systems. The most commonly used definition of CFS is 6 or more months of fatigue and the presence of at least four of eight minor symptoms. In addition, many health and psychological conditions, including severe obesity-body mass index (BMI) of 40 kg/m(2) or greater-exclude individuals from a diagnosis of CFS. Obesity has been correlated with fatigue, sleep problems, and less satisfaction with general health, functioning, and vitality.

The current study investigated weight trends over time in a community-based sample of individuals with CFS and healthy controls. The study further investigated the impact of comorbid weight issues on several health and disability outcomes in a subset of overweight individuals.

Overweight and obese individuals with CFS demonstrated poorer functioning than controls who were similarly weighted. One participant was excluded because she had gained weight at a monitoring visit and her BMI was greater than 40 kg/m(2). The implications of these findings for health care workers are discussed.

Copyright 2013, SLACK Incorporated.

 

Source: Flores S, Brown A, Adeoye S, Jason LA, Evans M. Examining the impact of obesity on individuals with chronic fatigue syndrome.Workplace Health Saf. 2013 Jul;61(7):299-307. doi: 10.3928/21650799-20130617-12. Epub 2013 Jun 24. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3899694/ (Full article)