Tag: Lloyd

Hit-and-run Injury To The Brain: New Evidence On Chronic Fatigue Causation

Press Release: A seven-year tracking study has prompted scientists to suggest that chronic fatigue syndrome could be the result of brain injuries inflicted during the early stages of glandular fever.

Australian researchers have put the suggestion in this week’s Journal of Infectious Diseases, which reveals new findings from the ‘Dubbo Infection Outcomes Study’. Since 1999, a team led by UNSW Professor Andrew Lloyd have been tracking the long-term health of individuals infected with Epstein-Barr virus (EBV), Ross River virus (RRV) or Q fever infection. Their goal is to discover whether the post-infection fatigue syndrome that may affect up to 100,000 Australians is caused by the persistence of EBV, a weakened immune system, psychological vulnerability, or some combination of these.

Glandular fever — sometimes called ‘the kissing disease’ — is caused by Epstein-Barr virus (EBV). Transmitted via saliva, its acute symptoms include fever, sore throat, tiredness, and swollen lymph glands. Most patients recover within several weeks but one in ten young people will suffer prolonged symptoms, marked by fatigue. When these symptoms persist in disabling degree for six months or more, the illness may be diagnosed as chronic fatigue syndrome (CFS).

The researchers followed the course of illness among 39 people diagnosed with acute glandular fever. Eight patients developed a ‘post-infective fatigue syndrome’ lasting six months or longer, while the remaining 31 recovered uneventfully. Detailed studies of the activity of the Epstein-Barr virus in the blood and the immune response against the virus were conducted on blood samples collected from each individual over 12 months.

Commenting on the findings, Professor Lloyd says: “Our findings reveal that neither the virus nor an abnormal immune response explain the post-infective fatigue syndrome. We now suspect it’s more like a hit and run injury to the brain.

“We believe that the parts of the brain that control perception of fatigue and pain get damaged during the acute infection phase of glandular fever. If you’re still sick several weeks after infection, it seems that the symptoms aren’t being driven by the activity of the virus in body, it’s happening in the brain.”

The research team comprising scientists from the University of New South Wales, the University of Sydney and the Queensland Institute of Medical Research plan to test their ‘brain injury’ hypothesis by doing neurological tests on the study participants.

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About the Dubbo Infection Outcomes Study: this is a major prospective cohort study following individuals from the time of onset of documented infection with Epstein-Barr virus (the cause of glandular fever), Ross River virus (the mosquito-borne infection which causes rash and joint pain) and Q fever (an infection common in meatworkers and those exposed to livestock).

Research Paper:
‘Prolonged illness after infectious mononucleosis is associated with altered immunity but not with increased viral load’, The Journal of Infectious Diseases, vol. 193 (2006), pp 664-671. Authors: Barbara Cameron, Mandvi Bharadwaj, Jacqueline Burrows, Chrysa Fazou, Denis Wakefield, Ian Hickie, Rosemary French, Rajiv Khanna, Andrew Lloyd.

Funding: The Dubbo Infection Outcomes Study is 82 per cent funded by the US Centers for Disease Control. It also receives funding from the National Health and Medical Research Council of Australia.

 

Source: University of New South Wales. “Hit-and-run Injury To The Brain: New Evidence On Chronic Fatigue Causation.” ScienceDaily. ScienceDaily, 1 March 2006. https://www.sciencedaily.com/releases/2006/03/060301092926.htm

 

Chronic Fatigue: Clues In The Blood

Press Release: University of New South Wales, July 8, 2007. Researchers at UNSW believe that blood may hold vital insights into what is happening in the brain of patients with chronic fatigue syndrome (CFS).

In a study unparalleled in its scope, a team led by UNSW Professor Andrew Lloyd of the Centre for Infection and Inflammation Research, has studied the differences in gene expression patterns in the blood of people who either recover promptly after acute glandular fever or develop the prolonged illness called post-infective syndrome.

The researchers examined six million pieces of gene expression information for analysis in the project, known as the Dubbo Infection Outcomes Study. The study is named after the NSW town in which the work was conducted. The team studied the expression of 30,000 genes in the blood, testing each of the 15 individuals between four and five times over a 12-month period.

The team was able to narrow its findings to the expression of just 35 genes whose pattern of expression correlated closely with the key symptoms of the illness when examined from onset through to recovery. Gene expression is significant because it is the process by which a gene’s DNA sequence is converted into the proteins which ultimately determine the manifestations of disease.

Since 1999, the team has been tracking the long-term health of individuals infected with Ross River virus (RRV), Q fever infection and Epstein-Barr virus, which causes glandular fever.

“These [35] genes might point to the nature of the disease process that underlies CFS, which is currently unknown,” said Professor Lloyd, who is based in the School of Medical Sciences at UNSW. “None of them are ones that I would have predicted, except for those relating to neurotransmitters,” he concedes. “Some of them relate to transport of zinc and other metal ions within the cell, which may suggest a fundamental disturbance in cellular function.”

The researchers now hope to narrow the focus of research onto the expression of these 35 genes in the blood of a much larger group of subjects from the Dubbo Infection Outcomes Study, with varied patterns of illness and recovery.

“There are very few complex diseases which have been comprehensively analysed, with large scale and longitudinal studies, like this,” said Professor Lloyd. “It sets a standard for highly sophisticated, comprehensive gene expression studies in the blood of all sorts of human diseases from rheumatoid arthritis and multiple sclerosis through to schizophrenia.”

The research paper has been published in the Journal of Infectious Diseases.

 

Source: University of New South Wales. “Chronic Fatigue: Clues In The Blood.” ScienceDaily. ScienceDaily, 8 July 2007. https://www.sciencedaily.com/releases/2007/07/070706090020.htm

Gene Expression in Response to Exercise in Patients with Chronic Fatigue Syndrome: A Pilot Study

Abstract:

Chronic fatigue syndrome (CFS) is a debilitating disorder of unknown pathogenesis, characterized by fatigue, which is exacerbated after minimal exercise. We examined the effect of a single bout of aerobic exercise on leucocyte mRNA expression of genes putatively linked to exaggerated afferent signaling as an under-pinning of the fatigue state.

A carefully-characterized sample of patients with CFS (N = 10) and healthy matched control participants (N = 12) were included. Participant ratings of fatigue and other symptoms, as well as blood samples, were obtained at baseline, and five other time-points up to 72 h after 25 min of moderate-intensity cycling exercise. Leucocyte mRNA of 19 metabolite-sensing, adrenergic, immune, and neurotransmission genes was examined using quantitative polymerase chain reaction.

Patients with CFS reported substantial fatigue, functional impairment, and poor sleep at baseline (all p < 0.02), and exercise immediately induced worsened patients’ fatigue (effect size, ES = 1.17).

There were no significant changes in gene expression after exercise and patients did not differ from control participants at any time point. Higher levels of expression of ficolin (FCN1) and a purinergic receptor (P2RX4) in patients with CFS were found when all time points were combined. Patients with CFS did not show significant exercise-induced changes in leucocyte mRNA of 19 metabolite-sensing, adrenergic, immune and neurotransmission genes despite a prominent exacerbation of fatigue.

 

Source: Keech A, Vollmer-Conna U, Barry BK, Lloyd AR. Gene Expression in Response to Exercise in Patients with Chronic Fatigue Syndrome: A Pilot Study. Front Physiol. 2016 Sep 22;7:421. eCollection 2016. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5031769/ (Full article)

 

Neurocognitive improvements after best-practice intervention for chronic fatigue syndrome: Preliminary evidence of divergence between objective indices and subjective perceptions

Abstract:

BACKGROUND: Neurocognitive difficulties are commonly reported by patients suffering from chronic fatigue syndrome (CFS). Moderate improvements from ‘best practice’ therapy are promising, but to date reported efficacy is based entirely on subjective measures. This is problematic, given the well-documented divergence between subjective perceptions and actual neurocognitive performance, including in this patient group.

MATERIAL AND METHODS: Subjective and objective measures of neurocognitive performance were obtained from 25 patients with well-characterized CFS before and after the completion of a 12-week graded-activity program incorporating a cognitive training component. Additionally, self-reported symptoms, cardiac autonomic activity (a relevant biomarker of stress responsivity), and their relation to neurocognitive improvements were examined.

RESULTS: Substantive post-intervention improvements in subjective (p=0.006) and objective (including faster responses speeds and greater accuracy, p’s<0.001) neurocognitive performance were documented. Participants also demonstrated reduced autonomic reactivity to the cognitive challenge at follow-up (p’s≤0.01). These improvements were accompanied by improvements in symptom ratings (p’s≤0.01). However, subjective ratings of neurocognitive difficulties, and CFS-related symptoms were not linked to objective performance improvements.

CONCLUSIONS: These initial data provide the first evidence of objective neurocognitive performance improvements accompanied by a significant reduction in responsiveness in stress-related neural pathways consequent to cognitive-behavioral/graded exercise therapy programs. These findings provide support for the effectiveness of such programs in remediating clinical status. These promising findings warrant further investigation, including replication in a larger sample utilizing more controlled study designs.

Copyright © 2016 Elsevier Inc. All rights reserved.

 

Source: Cvejic E, Lloyd AR, Vollmer-Conna U. Neurocognitive improvements after best-practice intervention for chronic fatigue syndrome: Preliminary evidence of divergence between objective indices and subjective perceptions. Compr Psychiatry. 2016 Apr;66:166-75. doi: 10.1016/j.comppsych.2016.02.002. Epub 2016 Feb 9. https://www.ncbi.nlm.nih.gov/pubmed/26995250

 

Capturing the post-exertional exacerbation of fatigue following physical and cognitive challenge in patients with chronic fatigue syndrome

Abstract:

OBJECTIVE: To design and validate an instrument to capture the characteristic post-exertional exacerbation of fatigue in patients with chronic fatigue syndrome (CFS).

METHODS: Firstly, patients with CFS (N=19) participated in five focus group discussions to jointly explore the nature of fatigue and dynamic changes after activity, and inform development of a self-report instrument – the Fatigue and Energy Scale (FES). The psychometric properties of the FES were then examined in two case-control challenge studies: a physically-demanding challenge (moderate-intensity aerobic exercise; N=10 patients), and a cognitively-demanding challenge (simulated driving; N=11 patients). Finally, ecological validity was evaluated by recording in association with tasks of daily living (N=9).

RESULTS: Common descriptors for fatigue included ‘exhaustion’, ‘tiredness’, ‘drained of energy’, ‘heaviness in the limbs’, and ‘foggy in the head’. Based on the qualitative data, fatigue was conceptualised as consisting of ‘physical’ and ‘cognitive’ dimensions. Analysis of the psychometric properties of the FES showed good sensitivity to the changing symptoms during a post-exertional exacerbation of fatigue following both physical exercise and driving simulation challenges, as well as tasks of daily living.

CONCLUSION: The ‘fatigue’ experienced by patients with CFS covers both physical and cognitive components. The FES captured the phenomenon of a post-exertional exacerbation of fatigue commonly reported by patients with CFS. The characteristics of the symptom response to physical and cognitive challenges were similar. Both the FES and the challenge paradigms offer key tools to reliably investigate biological correlates of the dynamic changes in fatigue.

Copyright © 2015 Elsevier Inc. All rights reserved.

 

Source: Keech A, Sandler CX, Vollmer-Conna U, Cvejic E, Lloyd AR, Barry BK. Capturing the post-exertional exacerbation of fatigue following physical and cognitive challenge in patients with chronic fatigue syndrome. J Psychosom Res. 2015 Dec;79(6):537-49. doi: 10.1016/j.jpsychores.2015.08.008. Epub 2015 Sep 2. https://www.ncbi.nlm.nih.gov/pubmed/26359713

 

Characterization of fatigue states in medicine and psychiatry by structured interview

Abstract:

CONTEXT: Unexplained fatigue states are prevalent, with uncertain diagnostic boundaries.

OBJECTIVE: Patients with fatigue-related illnesses were investigated by questionnaire and a novel semistructured interview to identify discriminatory features.

METHODS: Cross-sectional samples of women from specialist practices with chronic fatigue syndrome (n = 20), postcancer fatigue (PCF; n = 20), or major depression (n = 16) were recruited. Additionally, two longitudinal samples were studied: women with fatigue associated with acute infection who subsequently developed postinfective fatigue syndrome (n = 20) or recovered uneventfully (n = 21), and women undergoing adjuvant therapy for breast cancer experiencing treatment-related fatigue who subsequently developed PCF (n = 16) or recovered uneventfully (n = 16). Patients completed self-report questionnaires, and trained interviewers applied the Semi-structured Clinical Interview for Neurasthenia. The receiver operating characteristics curves of the interview were measured against clinician-designated diagnoses. Cluster analyses were performed to empirically partition participants by symptom characteristics.

RESULTS: The interview had good internal consistency (Cronbach alpha “fatigue” = .83), and diagnostic sensitivity and specificity for chronic fatigue syndrome (100% and 83%) and major depression (100% and 72%), with reasonable parameters for PCF (72% and 58%). Empirical clustering by “fatigue” or “neurocognitive difficulties” items allocated most patients to one group, whereas “mood disturbance” items correctly classified patients with depression only.

CONCLUSIONS: The Semi-structured Clinical Interview for Neurasthenia offers reliable diagnostic use in assessing fatigue-related conditions. The symptom domains of fatigue and neurocognitive difficulties are shared across medical and psychiatric boundaries, whereas symptoms of depression such as anhedonia are distinguishing.

 

Source: Bennett BK, Goldstein D, Chen M, Davenport TA, Vollmer-Conna U, Scott EM, Hickie IB, Lloyd AR. Characterization of fatigue states in medicine and psychiatry by structured interview. Psychosom Med. 2014 Jun;76(5):379-88. https://www.ncbi.nlm.nih.gov/pubmed/25076512

 

Apology

Dear Sir,

In our commentary [1] on paper by Broderick et al. regarding diagnostic criteria for CFS [2], Professor van Der Meer and I inadvertently cited a letter by Stouten et al. in a section of our correspondence suggesting that their response to the publication of the PACE [3] trial for patients with CFS was unscientific and included personal attacks on the authors of that study, as it was interspersed with a series of letters that met those descriptors. However, it is clear that the letter by Stouten et al. raised valid scientific concerns about the trial. We wish to note that this letter should not have been included as an example in our correspondence and apologize to the authors for any distress caused.

Comment on: A controversial consensus–comment on article by Broderick et al. [J Intern Med. 2012]

 

Source: Lloyd AR. Apology. J Intern Med. 2013 Jun;273(6):628. doi: 10.1111/joim.12074. Epub 2013 May 6. http://onlinelibrary.wiley.com/doi/10.1111/joim.12074/full (Full article)

 

Reduced cardiac vagal modulation impacts on cognitive performance in chronic fatigue syndrome

Abstract:

BACKGROUND: Cognitive difficulties and autonomic dysfunction have been reported separately in patients with chronic fatigue syndrome (CFS). A role for heart rate variability (HRV) in cognitive flexibility has been demonstrated in healthy individuals, but this relationship has not as yet been examined in CFS. The objective of this study was to examine the relationship between HRV and cognitive performance in patients with CFS.

METHODS: Participants were 30 patients with CFS and 40 healthy controls; the groups were matched for age, sex, education, body mass index, and hours of moderate exercise/week. Questionnaires were used to obtain relevant medical and demographic information, and assess current symptoms and functional impairment. Electrocardiograms, perceived fatigue/effort and performance data were recorded during cognitive tasks. Between-group differences in autonomic reactivity and associations with cognitive performance were analysed.

RESULTS: Patients with CFS showed no deficits in performance accuracy, but were significantly slower than healthy controls. CFS was further characterized by low and unresponsive HRV; greater heart rate (HR) reactivity and prolonged HR-recovery after cognitive challenge. Fatigue levels, perceived effort and distress did not affect cognitive performance. HRV was consistently associated with performance indices and significantly predicted variance in cognitive outcomes.

CONCLUSIONS: These findings reveal for the first time an association between reduced cardiac vagal tone and cognitive impairment in CFS and confirm previous reports of diminished vagal activity.

 

Source: Beaumont A, Burton AR, Lemon J, Bennett BK, Lloyd A, Vollmer-Conna U. Reduced cardiac vagal modulation impacts on cognitive performance in chronic fatigue syndrome. PLoS One. 2012;7(11):e49518. doi: 10.1371/journal.pone.0049518. Epub 2012 Nov 14. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3498107/ (Full article)

 

Family-focused cognitive behaviour therapy versus psycho-education for adolescents with chronic fatigue syndrome: long-term follow-up of an RCT

Abstract:

The aim of this study was to investigate the long term efficacy of family-focused cognitive behaviour therapy (CBT) compared with psycho-education in improving school attendance and other secondary outcomes in adolescents with chronic fatigue syndrome (CFS). A 24 month follow-up of a randomised controlled trial was carried out.

Participants received either 13 one-hour sessions of family-focused CBT or four one-hour sessions of psycho-education. Forty-four participants took part in the follow-up study. The proportion of participants reporting at least 70% school attendance (the primary outcome) at 24 months was 90% in CBT group and 84% in psycho-education group; the difference between the groups was not statistically significant (OR = 1.29, p = 0.80).

The proportion of adolescents who had recovered in the family-focused CBT group was 79% compared with 64% in the psycho-education, according to a definition including fatigue and school attendance. This difference was not statistically significant (Fisher’s exact test, p = 0.34). Family-focused CBT was associated with significantly better emotional and behavioural adjustment at 24 month follow-up compared to psycho-education, as reported by both adolescents (F = 6.49, p = 0.02) and parents (F = 4.52, P = 0.04). Impairment significantly decreased in both groups between six and 24 month follow-ups, with no significant group difference in improvement over this period. Gains previously observed for other secondary outcomes at six month follow-up were maintained at 24 month follow-up with no further significant improvement or group differences in improvement.

In conclusion, gains achieved by adolescents with CFS who had undertaken family-focused CBT and psycho-education generally continued or were maintained at two-year follow-up. The exception was that family-focused CBT was associated with maintained improvements in emotional and behavioural difficulties whereas psycho-education was associated with deterioration in these outcomes between six and 24-month follow-up.

Copyright © 2012 Elsevier Ltd. All rights reserved.

 

Source: Lloyd S, Chalder T, Rimes KA. Family-focused cognitive behaviour therapy versus psycho-education for adolescents with chronic fatigue syndrome: long-term follow-up of an RCT. Behav Res Ther. 2012 Nov;50(11):719-25. doi: 10.1016/j.brat.2012.08.005. Epub 2012 Aug 31. https://www.ncbi.nlm.nih.gov/pubmed/22985998

 

Peripheral blood gene expression in postinfective fatigue syndrome following from three different triggering infections

Abstract:

BACKGROUND: Several infections trigger postinfective fatigue syndromes, which share key illness characteristics with each other and with chronic fatigue syndrome (CFS). Previous cross-sectional case-control studies of CFS have suggested that unique gene expression signatures are evident in peripheral blood samples.

METHODS: Peripheral blood transcriptomes in samples collected longitudinally, in 18 subjects with a fatigue syndrome lasting ≥ 6 months after acute infection due to Epstein-Barr virus, Ross River virus, or Coxiella burnetii (Q fever), and 18 matched control subjects who had recovered promptly, were studied by microarray (n = 127) and confirmatory quantitative polymerase chain reaction (PCR). Gene expression patterns associated with CFS were sought by univariate statistics and regression modeling.

RESULTS: There were 23 genes with modest differential expression (0.6-2.3-fold change) in within-subject comparisons of early, symptomatic time points with late, recovered time points. There were modest differences found in 63 genes, either in cross-sectional comparison of cases and controls at 6 months after infection onset or in the regression model. There were 223 genes significantly correlated with individual symptom domains. Quantitative PCR confirmed 33 (73%) of 45 genes-none were consistent across cohorts.

CONCLUSIONS: Although the illness characteristics of patients with postinfective fatigue syndromes have more similarities than differences, no reliable peripheral blood gene expression correlate is evident.

 

Source: Galbraith S, Cameron B, Li H, Lau D, Vollmer-Conna U, Lloyd AR. Peripheral blood gene expression in postinfective fatigue syndrome following from three different triggering infections. J Infect Dis. 2011 Nov 15;204(10):1632-40. doi: 10.1093/infdis/jir612. Epub 2011 Sep 29. http://jid.oxfordjournals.org/content/204/10/1632.long (Full article)