Category: Cognitive Dysfunction

Increasing orthostatic stress impairs neurocognitive functioning in chronic fatigue syndrome with postural tachycardia syndrome

Abstract:

CFS (chronic fatigue syndrome) is commonly co-morbid with POTS (postural tachycardia syndrome). Individuals with CFS/POTS experience unrelenting fatigue, tachycardia during orthostatic stress and ill-defined neurocognitive impairment, often described as ‘mental fog’. We hypothesized that orthostatic stress causes neurocognitive impairment in CFS/POTS related to decreased CBFV (cerebral blood flow velocity).

A total of 16 CFS/POTS and 20 control subjects underwent graded tilt table testing (at 0, 15, 30, 45, 60 and 75°) with continuous cardiovascular, cerebrovascular, and respiratory monitoring and neurocognitive testing using an n-back task at each angle. The n-back task tests working memory, concentration, attention and information processing. The n-back task imposes increasing cognitive challenge with escalating (0-, 1-, 2-, 3- and 4-back) difficulty levels. Subject dropout due to orthostatic presyncope at each angle was similar between groups.

There were no n-back accuracy or RT (reaction time) differences between groups while supine. CFS/POTS subjects responded less correctly during the n-back task test and had greater nRT (normalized RT) at 45, 60 and 75°. Furthermore, at 75° CFS/POTS subjects responded less correctly and had greater nRT than controls during the 2-, 3- and 4-back tests. Changes in CBFV were not different between the groups and were not associated with n-back task test scores.

Thus we conclude that increasing orthostatic stress combined with a cognitive challenge impairs the neurocognitive abilities of working memory, accuracy and information processing in CFS/POTS, but that this is not related to changes in CBFV. Individuals with CFS/POTS should be aware that orthostatic stress may impair their neurocognitive abilities.

 

Source: Ocon AJ, Messer ZR, Medow MS, Stewart JM. Increasing orthostatic stress impairs neurocognitive functioning in chronic fatigue syndrome with postural tachycardia syndrome. Clin Sci (Lond). 2012 Mar;122(5):227-38. doi: 10.1042/CS20110241. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3368269/ (Full article)

 

Length of illness does not predict cognitive dysfunction in chronic fatigue syndrome

Abstract:

Neuropsychological studies have shown cognitive impairment in chronic fatigue syndrome (CFS), particularly in information-processing speed. The aim of this study was to examine the evolution of cognitive impairment in CFS. The evolution is one of the most disabling aspects of the CFS, and it has received little attention in the literature. Fifty-six women with CFS were assessed with neuropsychological tests. Patients were divided into three groups based on the duration of the disease. There were no differences between groups in terms of cognitive function. The cognitive impairment in CFS was not found to be more severe with longer disease duration. These data suggest that there is no progressive cognitive impairment in patients with CFS. Therefore, the cognitive deficits in CFS should be treated with cognitive rehabilitation programs focused on improving emotional distress associated to the illness and on promoting functional abilities.

 

Source: Santamarina-Perez P, Eiroa-Orosa FJ, Freniche V, Moreno-Mayos A, Alegre J, Saez N, Jacas C. Length of illness does not predict cognitive dysfunction in chronic fatigue syndrome. Appl Neuropsychol. 2011 Jul;18(3):216-22. Doi: 10.1080/09084282.2011.595448. https://www.ncbi.nlm.nih.gov/pubmed/21846221

 

Cognitive dysfunction and mental fatigue in childhood chronic fatigue syndrome–a 6-month follow-up study

Abstract:

OBJECTIVES: Cognitive function was investigated in patients with childhood type chronic fatigue syndrome (CCFS) using the modified advanced trail making test (mATMT).

METHODS: mATMT was performed on 19 patients with CCFS and 25 healthy controls of comparable age and sex. The effectiveness of combined treatment with cognitive behavioral therapy (CBT) and pharmacotherapy and its relationship to cognitive function was investigated by evaluation of Chalder’s fatigue scale and behavior state before and after treatment for 6 consecutive months.

RESULTS: All three tasks (motor skill, selective and alternative attention, and spatial working memory) of the mATMT, especially the difference in reaction time of the alternative attention task, could discriminate CCFS patients from control subjects with 70.5% accuracy (P=0.007). CCFS patients showed significantly lower alternative attention and Chalder’s fatigue score before treatment (P=0.037 and 0.002, respectively). A significant improvement in performance status scores was found during the 6 months follow-up period with combined treatment with CBT and medication (P<0.001). Improvement of their cognitive symptoms was significantly correlated with improvement of alternative attention (r=0.653, P=0.002).

CONCLUSIONS: Higher-order level cognitive dysfunction affects CCFS pathogenesis. Alternative attention performance evaluated by the mATMT may be used to monitor improvement in patients with CCFS. Combined treatment with CBT and medication may be effective to improve poor attention characteristics associated with CCFS.

Copyright © 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

 

Source: Kawatani J, Mizuno K, Shiraishi S, Takao M, Joudoi T, Fukuda S, Watanabe Y, Tomoda A. Cognitive dysfunction and mental fatigue in childhood chronic fatigue syndrome–a 6-month follow-up study. Brain Dev. 2011 Nov;33(10):832-41. doi: 10.1016/j.braindev.2010.12.009. Epub 2011 May 6. https://www.ncbi.nlm.nih.gov/pubmed/21530119

 

Cognitive deficits in patients with chronic fatigue syndrome compared to those with major depressive disorder and healthy controls

Abstract:

OBJECT: Chronic fatigue syndrome (CFS) patients report usually cognitive complaints. They also have frequently comorbid depression that can be considered a possible explanation for their cognitive dysfunction. We evaluated the cognitive performance of patients with CFS in comparison with a control group of healthy volunteers and a group of patients with MDD.

PATIENTS AND METHODS: Twenty-five patients with CFS, 25 patients with major depressive disorder (MDD), and 25 healthy control subjects were given standardized tests of attention, working memory, and verbal and visual episodic memory, and were also tested for effects related to lack of effort/simulation, suggestibility, and fatigue.

RESULTS: Patients with CFS had slower phasic alertness, and also had impaired working, visual and verbal episodic memory compared to controls. They were, however, no more sensitive than the other groups to suggestibility or to fatigue induced during the cognitive session. Cognitive impairments in MDD patients were strongly associated with depression and subjective fatigue; in patients with CFS, there was a weaker correlation between cognition and depression (and no correlation with fatigue).

CONCLUSIONS: This study confirms the presence of an objective impairment in attention and memory in patients with CFS but with good mobilization of effort and without exaggerated suggestibility.

Copyright © 2011 Elsevier B.V. All rights reserved.

 

Source: Constant EL, Adam S, Gillain B, Lambert M, Masquelier E, Seron X. Cognitive deficits in patients with chronic fatigue syndrome compared to those with major depressive disorder and healthy controls. Clin Neurol Neurosurg. 2011 May;113(4):295-302. doi: 10.1016/j.clineuro.2010.12.002. Epub 2011 Jan 20. https://www.ncbi.nlm.nih.gov/pubmed/21255911

 

Cognitive impairment in fatigue and sleepiness associated conditions

Abstract:

Although relating to very different concepts, sleepiness and fatigue are often confounded. However, both fatigue-associated conditions such as the chronic fatigue syndrome (CFS) and sleepiness-associated conditions such as the sleep apnea-hypopnea syndrome (SAHS) are associated with cognitive impairment with impaired attention, concentration and memory performances.

Fifteen pure CFS patients, without primary sleep disorders or clinically relevant sleepiness, were compared to 15 untreated SAHS patients, without clinically relevant fatigue, and to 16 healthy controls of similar age. The auditory verbal learning test (AVLT), digit span, digit symbol and finger tapping test (FTT) were used as cognitive and behavioural measures. In addition we assessed daytime EEG spectral power and P300 evoked potentials.

With exception for the digit span, all tests showed lower performances in patient groups. Recall on the AVLT did not differ between the two patient groups, but the digit and symbol spans showed more severe impairment in SAHS patients. Psychomotor performance on the FTT presented with slower hit rates in SAHS than in CFS. EEG theta power was highest in CFS patients. P300 latencies and amplitudes did not differ between groups.

Fatigue- and sleepiness-associated conditions can both present with significant and objective impairment of cognitive functioning and behavioural motor performance. In our sample cognitive impairment and psychomotor performance were worse when associated to sleepiness in SAHS than with fatigue in CFS.

Copyright © 2010 Elsevier Ltd. All rights reserved.

 

Source: Neu D, Kajosch H, Peigneux P, Verbanck P, Linkowski P, Le Bon O. Cognitive impairment in fatigue and sleepiness associated conditions. Psychiatry Res. 2011 Aug 30;189(1):128-34. doi: 10.1016/j.psychres.2010.12.005. Epub 2010 Dec 31. https://www.ncbi.nlm.nih.gov/pubmed/21196050

 

The role of depression in cognitive impairment in patients with chronic fatigue syndrome

Abstract:

BACKGROUND AND OBJECTIVE: To analyze the role of depression in cognitive deficits of patients with chronic fatigue syndrome (CFS).

PATIENTS AND METHODS: 57 women with CFS were assessed by neuropsychological tests that included measures of attention: CalCap, Mental control of the WMS-III, PASAT, forward and backward digits (WAIS-III), symbol digit modalities test (SDMT); executive functions: Stroop Test, Trail Making Test (TMT A y B), FAS, Tower of London; memory: Auditory-Verbal Learning Test (AVL), Rey Complex Figure (RCF), and psychomotor skills: Grooved Pegboard. The raw scores on the tests were adjusted according to normative data and transformed to T scores. The sample was divided into two groups based on the presence or absence of depression, assessed by clinical interview and administration of the Hospital Anxiety and Depression Scale (HADS). This study compared neuropsychological test scores between the two groups.

RESULTS: CFS patients showed cognitive deficit in attention and executive functions, regardless of the presence of depression. There were no significant differences between the two CFS groups.

CONCLUSIONS: The cognitive impairments in patients with CFS are not secondary to the presence of depression. These results should be taken into account in the implementation of therapeutic programs in these patients.

Copyright © 2010 Elsevier España, S.L. All rights reserved.

 

Source: Santamarina-Pérez P, Freniche V, Eiroa-Orosa FJ, Llobet G, Sáez N, Alegre J, Jacas C. The role of depression in cognitive impairment in patients with chronic fatigue syndrome. Med Clin (Barc). 2011 Mar 12;136(6):239-43. doi: 10.1016/j.medcli.2010.07.022. Epub 2010 Dec 9. [Article in Spanish] https://www.ncbi.nlm.nih.gov/pubmed/21145567

 

Psychomotor function and response inhibition in chronic fatigue syndrome

Abstract:

Most research points to cognitive slowing in chronic fatigue syndrome (CFS), although there have been negative reports. The present study is one of few that examines fine motor processing and the inhibition of automatic responses in a well-characterised CFS population.

A total of 35 female CFS patients without current major depression and 25 female controls performed two computerised figure-copying tasks. The cognitive and fine motor processing of visual-spatial information was measured by recording reaction time (RT) and movement time (MT), respectively. The inhibition of automatic responses was assessed by introducing ‘conflicting patterns’ (i.e., patterns that were difficult to draw from the preferred left to right).

A multivariate general linear model was adopted for the statistical analysis of the movement recordings. As a result, CFS was significantly associated with longer RT and MT in the pooled and in the task-specific analyses. However, there was no interaction between disease status and conflicting character of the patterns.

In conclusion, these performance data on the figure-copying tasks provide confirmatory evidence for psychomotor slowing in CFS, but not for a disturbed inhibition of automatic responses. Computerised figure-copying tasks may be promising tools for use in neurobiological research and clinical trials in CFS.

Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

 

Source: Van Den Eede F, Moorkens G, Hulstijn W, Maas Y, Schrijvers D, Stevens SR, Cosyns P, Claes SJ, Sabbe BG. Psychomotor function and response inhibition in chronic fatigue syndrome. Psychiatry Res. 2011 Apr 30;186(2-3):367-72. doi: 10.1016/j.psychres.2010.07.022. Epub 2010 Aug 24. https://www.ncbi.nlm.nih.gov/pubmed/20797797

 

Autonomic hyper-vigilance in post-infective fatigue syndrome

Abstract:

This study examined whether post-infective fatigue syndrome (PIFS) is associated with a disturbance in bidirectional autonomic signalling resulting in heightened perception of symptoms and sensations from the body in conjunction with autonomic hyper-reactivity to perceived challenges.

We studied 23 patients with PIFS and 25 healthy matched control subjects. A heartbeat discrimination task and a pressure pain threshold test were used to assess interoceptive sensitivity. Cardiac response was assessed over a 4-min Stroop task. PIFS was associated with higher accuracy in heartbeat discrimination and a lower pressure pain threshold. Increased interoceptive sensitivity correlated strongly with current symptoms and potentiated differences in the cardiac response to the Stroop task, which in PIFS was characterized by insensitivity to task difficulty and lack of habituation.

Our results provide the first evidence of heightened interoceptive sensitivity in PIFS. Together with the distinct pattern in cardiac responsivity these findings present a picture of physiological hyper-vigilance and response inflexibility.

Copyright (c) 2010 Elsevier B.V. All rights reserved.

 

Source: Kadota Y, Cooper G, Burton AR, Lemon J, Schall U, Lloyd A, Vollmer-Conna U/ Autonomic hyper-vigilance in post-infective fatigue syndrome. Biol Psychol. 2010 Sep;85(1):97-103. doi: 10.1016/j.biopsycho.2010.05.009. Epub 2010 Jun 2. https://www.ncbi.nlm.nih.gov/pubmed/20678991

 

Cognitive functioning in chronic fatigue syndrome: a meta-analysis

Abstract:

BACKGROUND: Cognitive problems are commonly reported in persons with chronic fatigue syndrome (CFS) and are one of the most disabling symptoms of this condition. A number of cognitive deficits have been identified, although the findings are inconsistent and hindered by methodological differences. The current study therefore conducted a meta-analysis of research examining cognitive functioning in persons with CFS in order to identify the pattern and magnitude of any deficits that are associated with this condition.

METHOD: A comprehensive search of the PubMed and PsycINFO databases for studies that examined cognitive functioning in CFS between 1988 and 2008 identified 50 eligible studies. Weighted Cohen’s d effect sizes, 95% confidence intervals and fail-safe Ns were calculated for each cognitive score.

RESULTS: Evidence of cognitive deficits in persons with CFS was found primarily in the domains of attention, memory and reaction time. Deficits were not apparent on tests of fine motor speed, vocabulary, reasoning and global functioning.

CONCLUSIONS: Persons with CFS demonstrate moderate to large impairments in simple and complex information processing speed and in tasks requiring working memory over a sustained period of time.

Comment in: Letter to the Editor: Plausible explanations for neurocognitive deficits in ME/CFS, aggravation of neurocognitive impairment induced by exertion. [Psychol Med. 2010]

 

Source: Cockshell SJ, Mathias JL. Cognitive functioning in chronic fatigue syndrome: a meta-analysis. Psychol Med. 2010 Aug;40(8):1253-67. doi: 10.1017/S0033291709992054. Epub 2010 Jan 5. https://www.ncbi.nlm.nih.gov/pubmed/20047703

 

Coenzyme Q10 deficiency in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is related to fatigue, autonomic and neurocognitive symptoms and is another risk factor explaining the early mortality in ME/CFS due to cardiovascular disorder

Abstract:

INTRODUCTION: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a medical illness characterized by disorders in inflammatory and oxidative and nitrosative (IO&NS) pathways.

METHODS: This paper examines the role of Coenzyme Q10 (CoQ10), a mitochondrial nutrient which acts as an essential cofactor for the production of ATP in mitochondria and which displays significant antioxidant activities. Plasma CoQ10 has been assayed in 58 patients with ME/CFS and in 22 normal controls; the relationships between CoQ10 and the severity of ME/CFS as measured by means of the FibroFatigue (FF) scale were measured.

RESULTS: Plasma CoQ10 was significantly (p=0.00001) lower in ME/CFS patients than in normal controls. Up to 44.8% of patients with ME/CFS had values beneath the lowest plasma CoQ10 value detected in the normal controls, i.e. 490 microg/L. In ME/CFS, there were significant and inverse relationships between CoQ10 and the total score on the FF scale, fatigue and autonomic symptoms. Patients with very low CoQ10 (<390 microg/L) suffered significantly more from concentration and memory disturbances.

DISCUSSION: The results show that lowered levels of CoQ10 play a role in the pathophysiology of ME/CFS and that symptoms, such as fatigue, and autonomic and neurocognitive symptoms may be caused by CoQ10 depletion. Our results suggest that patients with ME/CFS would benefit from CoQ10 supplementation in order to normalize the low CoQ10 syndrome and the IO&NS disorders. The findings that lower CoQ10 is an independent predictor of chronic heart failure (CHF) and mortality due to CHF may explain previous reports that the mean age of ME/CFS patients dying from CHF is 25 years younger than the age of those dying from CHF in the general population. Since statins significantly decrease plasma CoQ10, ME/CFS should be regarded as a relative contraindication for treatment with statins without CoQ10 supplementation.

 

Source: Maes M, Mihaylova I, Kubera M, Uytterhoeven M, Vrydags N, Bosmans E. Coenzyme Q10 deficiency in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is related to fatigue, autonomic and neurocognitive symptoms and is another risk factor explaining the early mortality in ME/CFS due to cardiovascular disorder. Neuro Endocrinol Lett. 2009;30(4):470-6. https://www.ncbi.nlm.nih.gov/pubmed/20010505