Tag: alpha-wave intrusion

High slow-wave sleep and low-light sleep: chronic fatigue syndrome is not likely to be a primary sleep disorder

Abstract:

The status of chronic fatigue syndrome (CFS) is still under debate. Mainstream views still often consider it as an undetected primary sleep disorder or as the psychosomatic expression of a related anxiety or depression syndrome. Both primary sleep disorder and CFS are often related to unrefreshing sleep and affective daytime symptoms.

The present study compares nonrapid eye movement sleep distribution between patients with a primary sleep disorder and “pure” CFS patients without sleep or mood disorders. Intensity measures of affective symptoms are also analyzed. Sleep variables of 32 pure CFS (mean age, 41.9 +/- 8.7 years; 25 women), 30 Sleep Apnea Hypopnea Syndrome patients (mean age, 43.7 +/- 6.7 years; 13 women), and 14 healthy controls (mean age, 40.2 +/- 7.6 years; 9 women) were compared. Related affective symptoms were assessed using the self-reported Zung anxiety and depression scales.

The study confirms previous reports on increased slow-wave sleep in CFS patients. Both patient groups showed similar sleep duration and efficiency. Sleep efficiency was lower in both patient groups compared with controls. CFS patients showed a higher microarousal index than controls. Anxiety, but not depression symptoms were more intense in the CFS group. The distribution of nonrapid eye movement sleep in CFS differs sizeably from what can be observed in a primary sleep disorder.

 

Source: Neu D, Cappeliez B, Hoffmann G, Verbanck P, Linkowski P, Le Bon O. High slow-wave sleep and low-light sleep: chronic fatigue syndrome is not likely to be a primary sleep disorder. J Clin Neurophysiol. 2009 Jun;26(3):207-12. doi: 10.1097/WNP.0b013e3181a1841b. https://www.ncbi.nlm.nih.gov/pubmed/19424087

 

Determination of observer-rated alpha activity during sleep

Abstract:

Patients suffering from chronic fatigue syndrome (CFS) have been described as having alpha intrusion into sleep. In a separate study of the relationship between depression and CFS, we investigated the sleep of CFS patients.

We could not detect any observable alpha anomaly in our group of CFS patients. It is possible that there is a subgroup of CFS patients in whom no alpha anomaly is present. However, the sleep electroencephalogram (EEG) montage used in our study was different to that employed by previous researchers.

This paper investigates the influence of electrode derivations on the outcome of observable alpha ratings. We compared simultaneous recordings of sleep EEG using three commonly employed montages.

Our results indicate that use of the mastoid reference (montage 1) results in the highest observer-related alpha. This may suggest that data regarding alpha intrusion should always be collected using montage 1.

However, there is a possibility that the mastoid electrode is not electrically silent and is contaminating the data of the referenced channels. The implications of these findings are discussed in relation to the validity of alpha intrusion measurement of CFS and fibromyalgia.

 

Source: Flanigan MJ, Morehouse RL, Shapiro CM. Determination of observer-rated alpha activity during sleep. Sleep. 1995 Oct;18(8):702-6. http://www.ncbi.nlm.nih.gov/pubmed/8560138

 

ABC of sleep disorders. Sleep problems in patients with medical illness

Sleep complaints are ubiquitous in patients with medical illness. A recent survey of outpatients attending hospital clinics indicated that the vast majority of patients reported sleep disruption concomitant with their condition. The proportion with complaints (> 70%) was more than twice that among control subjects. Doctors rarely ask about sleep problems in the context of medical illness despite the fact that the patient’s first complaint disruption of sleep architecture in may be that a particular symptom caused sleep disruption.

There are specific reasons for sleep disruptions in patients with medical illness-for example, people are often deprived of sleep before an operation. Polysomnography has shown that there is a preoperative of sleep) reduction in slow wave sleep and that this is related to the anticipated importance of surgery. The increase in deep sleep that occurs after an operation is thought to facilitate the healing process.

A variety of sleep variables may be influenced by specific disorders and each of these effects is likely to differ. A decrease in deep (slow wave) sleep, for example, may lead to a sensation of having low energy, whereas repeated interruption of sleep may lead to daytime sleepiness.

Drugs may also disrupt sleep architecture by suppressing rapid eye movement (REM) sleep or by causing a withdrawal effect during the night. In both cases the drug clearly alters sleep, but the impact on health and recovery may differ.

Fatigue is common in several medical conditions. Clinicians, researchers, and patients themselves claim that the fatigue experienced in certain medical conditions differs qualitatively from the experience of tiredness or sleepiness. However, there have been few attempts to separate these states. In this article we provide an overview of the impact of medical disorders on sleep.

You can read the rest of this article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1677972/pdf/bmj00023-0050.pdf

 

Source: Shapiro CM, Devins GM, Hussain MR. ABC of sleep disorders. Sleep problems in patients with medical illness. BMJ. 1993 Jun 5;306(6891):1532-5. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1677972/

 

Fibromyalgia, sleep disorder and chronic fatigue syndrome

Abstract:

Various research studies show that the amalgam of disordered sleep physiology, chronic fatigue, diffuse myalgia, and cognitive and behavioural symptoms constitutes a non-restorative sleep syndrome that may follow a febrile illness, as in the chronic fatigue syndrome. Where rheumatic complaints are prominent such a constellation of disturbed sleep physiology and symptoms also characterizes the fibromyalgia disorder.

In contrast to the chronic fatigue syndrome, fibromyalgia is associated with a variety of initiating or perpetuating factors such as psychologically distressing events, primary sleep disorders (e.g. sleep apnoea, periodic limb movement disorder) and inflammatory rheumatic disease, as well as an acute febrile illness.

The chronic fatigue syndrome and fibromyalgia have similar disordered sleep physiology, namely an alpha rhythm disturbance (7.5-11 Hz) in the electroencephalogram (EEG) within non-rapid eye movement (NREM) sleep that accompanies increased nocturnal vigilance and light, unrefreshing sleep. Aspects of cytokine and cellular immune functions are shown to be related to the sleep-wake system.

The evidence suggests a reciprocal relationship of the immune and sleep-wake systems. Interference either with the immune system (e.g. by a viral agent or by cytokines such as alpha-interferon or interleukin 2) or with the sleeping-waking brain system (e.g. by sleep deprivation) has effects on the other system and will be accompanied by the symptoms of the chronic fatigue syndrome.

 

Source: Moldofsky H. Fibromyalgia, sleep disorder and chronic fatigue syndrome. Ciba Found Symp. 1993;173:262-71; discussion 272-9. http://www.ncbi.nlm.nih.gov/pubmed/8491102

 

Neuro-psychiatric aspects of chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is easily differentiated from various neurological organic disorders by conventional clinical examinations. The most important disease for distinguishment from CFS is fibromyalgia syndrome, in which the prominent and cardinal feature is a deprivation of stage 4 slow wave sleep.

Experimentally, the sleep disturbance in controls can induce general myalgia, muscle tender points, severe fatigue and stiffness on awakening. The EEG abnormality is slow alpha wave contaminants on slow wave background, which is identical to EEG of CFS. The results clearly imply that CFS is not a hysterical or psychogenic disease, and that fibromyalgia may be a central fundamental of CFS.

Fibromyalgia, however, has distinct features such as no antecedent inflammatory process and no endemics. Therefore, the syndrome has features distinct from, in addition to common features to CFS. It is also very difficult to distinguish CFS from depression. The above-mentioned features can be observed in depression. Now, study of brain blood flow or metabolism by PET or SPECT can be a possible tool for establishment of the CFS identity.

 

Source: Shimizu T. Neuro-psychiatric aspects of chronic fatigue syndrome. Nihon Rinsho. 1992 Nov;50(11):2630-4. [Article in Japanese] http://www.ncbi.nlm.nih.gov/pubmed/1287239

 

Sleep, Epstein-Barr virus infection, musculoskeletal pain, and depressive symptoms in chronic fatigue syndrome

Abstract:

Sleep physiology, viral serology and symptoms of 14 patients with chronic fatigue syndrome (CFS) were compared with 12 healthy controls. All patients described unrefreshing sleep and showed a prominent alpha electroencephalographic nonrapid eye movement (7.5-11.0 Hz) sleep anomaly (p less than or equal to 0.001), but had no physiologic daytime sleepiness.

There were no group differences in Epstein-Barr virus (EBV) antibody titers. The patient group had more fibrositis tender points (p less than 0.0001), described more somatic complaints (p less than 0.0001), and more depressive symptoms (p less than 0.0001). Patients with CFS do not show evidence for a specific chronic EBV infection, but show altered sleep physiology, numerous tender points, diffuse pain, and depressive symptoms. These features are similar to those found in fibromyalgia syndrome.

 

Source: Whelton CL, Salit I, Moldofsky H. Sleep, Epstein-Barr virus infection, musculoskeletal pain, and depressive symptoms in chronic fatigue syndrome. J Rheumatol. 1992 Jun;19(6):939-43. http://www.ncbi.nlm.nih.gov/pubmed/1328633

 

Fibromyalgia and parvovirus infection

Abstract:

An infectious cause of fibromyalgia (FM) has been hypothesized based upon the observed similarity of this entity and chronic fatigue syndrome. Three patients developed symptoms of FM after documented episodes of acute parvovirus B19 infections. B19 antibody determinations were obtained approximately 1 month after the symptoms began; both IgM and IgG titers were positive at that time. All 3 patients met criteria for FM. Polysomnography performed on 2 of the patients revealed profound alpha-wave intrusion throughout nonrapid eye movement sleep. A more careful search for viral infections in FM patients whose symptoms appear following a “flu-like” illness appears warranted.

 

Source: Leventhal LJ, Naides SJ, Freundlich B. Fibromyalgia and parvovirus infection. Arthritis Rheum. 1991 Oct;34(10):1319-24. http://www.ncbi.nlm.nih.gov/pubmed/1657005