Category: Symptoms

Periodic K-alpha sleep EEG activity and periodic limb movements during sleep: comparisons of clinical features and sleep parameters

Abstract:

The K-alpha sleep electroencephalographic (EEG) phenomenon is characterized by periodic (approximately 20-40 seconds) K-complexes, immediately followed by alpha-EEG activity (7.5-11 Hz) of 0.5- to 5.0-second duration. A group of 14 subjects with the periodic K-alpha anomaly was found to have a similar distribution pattern of interevent intervals as compared with previously published data for sleep-related periodic limb movements during sleep (PLMS). Sleep parameters and somatic symptoms of 30 patients with K-alpha were compared with 30 patients with PLMS. The periodic K-alpha group was predominantly female, younger, exhibiting more slow-wave sleep, gastrointestinal symptoms and muscular complaints and fewer movement arousals on overnight polysomnography. The K-alpha group presented uniformly with complaints of unrefreshing sleep, often associated with fibromyalgia and chronic fatigue syndrome. The PLMS group was predominantly male, showed greater sleep disruption and presented with a variety of sleep-related symptoms.

 

Source: MacFarlane JG, Shahal B, Mously C, Moldofsky H. Periodic K-alpha sleep EEG activity and periodic limb movements during sleep: comparisons of clinical features and sleep parameters. Sleep. 1996 Apr;19(3):200-4. http://www.ncbi.nlm.nih.gov/pubmed/8723376

 

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

 

Gait abnormalities in chronic fatigue syndrome

Abstract:

To evaluate our clinical impression that patients with the chronic fatigue syndrome (CFS) did not walk normally, we assessed gait kinematics at slow walking speeds (i.e., 0.45, 0.89 and 1.34 m/sec) and 30 m run time speeds on CFS patients and on a comparison group of sedentary controls.

Run time was significantly slower for CFS than control subjects (p < 0.001). There was a significant interaction (p < 0.01) between group and speed for maximum hip angle during stance and swing phase with hip angle being significantly larger at 1.34 m/sec for CFS than controls subjects for both cases (p < 0.05). Knee flexion during stance and swing phases was significantly larger for controls than CFS subjects at 0.45 m/sec (p < 0.01). Ratio of stride length divided by leg length was significantly larger for the control subjects than for the CFS subjects with differences occurring at 0.45 and 0.89 m/sec (p < 0.01) but not 1.34 m/sec.

The data indicate that CFS patients have gait abnormalities when compared to sedentary controls. These could be due to balance problems, muscle weakness, or central nervous system dysfunction; deciding which will require further research. Evaluation of gait may be a useful tool to measure outcome following therapeutic interventions.

 

Source: Boda WL, Natelson BH, Sisto SA, Tapp WN. Gait abnormalities in chronic fatigue syndrome. J Neurol Sci. 1995 Aug;131(2):156-61. http://www.ncbi.nlm.nih.gov/pubmed/7595641

 

The Multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue

Abstract:

The Multidimensional Fatigue Inventory (MFI) is a 20-item self-report instrument designed to measure fatigue. It covers the following dimensions: General Fatigue, Physical Fatigue, Mental Fatigue, Reduced Motivation and Reduced Activity. This new instrument was tested for its psychometric properties in cancer patients receiving radiotherapy, patients with the chronic fatigue syndrome, psychology students, medical students, army recruits and junior physicians. We determined the dimensional structure using confirmatory factor analyses (LISREL’s unweighted least squares method). The hypothesized five-factor model appeared to fit the data in all samples tested (AGFIs > 0.93). The instrument was found to have good internal consistency, with an average Cronbach’s alpha coefficient of 0.84. Construct validity was established after comparisons between and within groups, assuming differences in fatigue based on differences in circumstances and/or activity level. Convergent validity was investigated by correlating the MFI-scales with a Visual Analogue Scale measuring fatigue (0.22 < r < 0.78). Results, by and large, support the validity of the MFI.

 

Source: Smets EM, Garssen B, Bonke B, De Haes JC. The Multidimensional Fatigue Inventory (MFI) psychometric qualities of an instrument to assess fatigue. J Psychosom Res. 1995 Apr;39(3):315-25. http://www.ncbi.nlm.nih.gov/pubmed/7636775

 

Is neurally mediated hypotension an unrecognised cause of chronic fatigue?

Abstract:

Neurally mediated hypotension is now recognised as a common cause of otherwise unexplained recurrent syncope, but has not been reported in association with chronic fatigue. We describe seven consecutive non-syncopal adolescents with chronic post-exertional fatigue, four of whom satisfied strict criteria for chronic fatigue syndrome. Upright tilt-table testing induced significant hypotension in all seven (median systolic blood pressure 65 mm Hg, range 37-75), consistent with the physiology of neurally mediated hypotension. Four had prompt improvement in their chronic fatigue when treated with atenolol or disopyramide. These observations suggest an overlap in the symptoms of chronic fatigue syndrome and neurally mediated hypotension.

Comment in:

Is neurally mediated hypotension an unrecognised cause of chronic fatigue? [Lancet. 1995]

Is neurally mediated hypotension an unrecognised cause of chronic fatigue? [Lancet. 1995]

Is neurally mediated hypotension an unrecognised cause of chronic fatigue? [Lancet. 1995]

 

Source: Rowe PC, Bou-Holaigah I, Kan JS, Calkins H. Is neurally mediated hypotension an unrecognised cause of chronic fatigue? Lancet. 1995 Mar 11;345(8950):623-4. http://www.ncbi.nlm.nih.gov/pubmed/7898182

 

Sleep disturbances and fatigue in women with fibromyalgia and chronic fatigue syndrome

Abstract:

OBJECTIVE: To determine the relationship between sleep disturbances and fatigue in women with fibromyalgia (FM) and those with chronic fatigue syndrome (CFS) and to assess whether any differences existed between the two groups.

DESIGN: Descriptive comparative.

SETTING: Community program on chronic fatigue syndrome and related disorders.

PARTICIPANTS: Sixty-three women who attended the program; 13 had CFS, and 50 had FM.

MAIN OUTCOME MEASURES: A moderately strong relationship between fatigue and sleepiness was found (r = .63, p < .01). Trouble staying asleep was the highest rated sleep disturbance, and fatigue was the most common subjective feeling reported. Women with CFS reported significantly more trouble staying asleep than women with FM, t(61) = 1.81, p < .03.

CONCLUSIONS: Data from this study support that women with FM and CFS encounter problems sleeping. Clinicians are encouraged to assess women with FM and CFS for their quality of sleep rather than amount of sleep. Researchers are encouraged to continue study of sleep disturbances in women with FM and CFS to improve understanding of the disturbances and to test the effectiveness of sleep interventions.

 

Source: Schaefer KM. Sleep disturbances and fatigue in women with fibromyalgia and chronic fatigue syndrome. J Obstet Gynecol Neonatal Nurs. 1995 Mar-Apr;24(3):229-33. http://www.ncbi.nlm.nih.gov/pubmed/7782955

 

Serum levels of carnitine in chronic fatigue syndrome: clinical correlates

Abstract:

Carnitine is essential for mitochondrial energy production. Disturbance in mitochondrial function may contribute to or cause the fatigue seen in chronic fatigue syndrome (CFS) patients. One previous investigation has reported decreased acylcarnitine levels in 38 CFS patients.

We investigated 35 CFS patients (27 females and 8 males); our results indicate that CFS patients have statistically significantly lower serum total carnitine, free carnitine and acylcarnitine levels, not only lower acylcarnitine levels as previously reported. We also found a statistically significant correlation between serum levels of total and free carnitine and clinical symptomatology. Higher serum carnitine levels correlated with better functional capacity.

These findings may be indicative of mitochondrial dysfunction, which may contribute to or cause symptoms of fatigue in CFS patients.

 

Source: Plioplys AV, Plioplys S. Serum levels of carnitine in chronic fatigue syndrome: clinical correlates. Neuropsychobiology. 1995;32(3):132-8. http://www.ncbi.nlm.nih.gov/pubmed/8544970

 

Sleep, neuroimmune and neuroendocrine functions in fibromyalgia and chronic fatigue syndrome

Abstract:

The justification for disordered chronobiology for fibromyalgia and chronic fatigue syndrome (CFS) is based on the following evidence: The studies on disordered sleep physiology and the symptoms of fibromyalgia and CFS; the experimental studies that draw a link between interleukin-1 (IL-1), immune-neuroendocrine-thermal systems and the sleep-wake cycle; studies and preliminary data of the inter-relationships of sleep-wakefulness, IL-1, and aspects of peripheral immune and neuroendocrine functions in healthy men and in women during differing phases of the menstrual cycle; and the observations of alterations in the immune-neuroendocrine functions of patients with fibromyalgia and CFS (Moldofsky, 1993b, d). Time series analyses of measures of the circadian pattern of the sleep-wake behavioural system, immune, neuroendocrine and temperature functions in patients with fibromyalgia and CFS should determine whether alterations of aspects of the neuro-immune-endocrine systems that accompany disordered sleep physiology result in nonrestorative sleep, pain, fatigue, cognitive and mood symptoms in patients with fibromyalgia and CFS.

 

Source: Moldofsky H. Sleep, neuroimmune and neuroendocrine functions in fibromyalgia and chronic fatigue syndrome. Adv Neuroimmunol. 1995;5(1):39-56. http://www.ncbi.nlm.nih.gov/pubmed/7795892

 

Vestibular function test anomalies in patients with chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is distinguished by the new onset of debilitating fatigue that lasts at least 6 months, concomitant with other symptoms to be described later. Many CFS patients complain of disequilibrium, yet the exact type of the balance dysfunction and its function and its location (peripheral vs. central) have not been described.

Herein we report results of vestibular function testing performed on 11 CFS patients. These results revealed no predominant pattern of abnormalities. Patients typically performed below average in dynamic posturography testing, with a significant number of falls in the tests requiring subjects to depend heavily on the vestibular system. One patient had abnormal caloric testing, while 3 had abnormally low earth vertical axis rotation (EVA) gains at the higher frequencies tested.

As a group, the average gain of EVA was significantly lower than normals in the 0.1 – 1.0 Hz range (p < 0.05). In earth horizontal axis rotation, the CFS group had a higher than normal bias value for the optokinetic (OKN) and eyes open in the dark conditions (p < 0.05), but had normal scores during visual vestibular reflex testing. Five of the 11 subjects had an abnormal OKN bias build up over the course of the run, equal to or actually exceeding the 60 degrees/s target velocity by as much as 14 degrees/s.

Altogether, these results are more suggestive of central nervous system deficits than of peripheral vestibular disfunction.

 

Source: Ash-Bernal R, Wall C 3rd, Komaroff AL, Bell D, Oas JG, Payman RN, Fagioli LR. Vestibular function test anomalies in patients with chronic fatigue syndrome. Acta Otolaryngol. 1995 Jan;115(1):9-17. http://www.ncbi.nlm.nih.gov/pubmed/7762393

 

Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS), fibromyalgia (FM), and multiple chemical sensitivities (MCS) are conditions associated with fatigue and a variety of other symptoms that appear to share many clinical and demographic features. Our objectives were to describe the similarities and differences among patients with CFS, FM, and MCS. Additional objectives were to determine how frequently patients with MCS and FM met the criteria for CFS and if they differed in their health locus of control.

METHODS: Demographic, clinical, and psychosocial measures were prospectively collected in 90 patients, 30 each with CFS, FM, and MCS. Patients were recruited from a university-based referral clinic devoted to the evaluation and treatment of chronic fatigue and three private practices. Variables included demographic features, symptoms characteristic of each condition, psychological complaints, a measure of health locus of control, and information on health care use.

RESULTS: Overall, the three patient groups were remarkably similar in demographic characteristics and the presence of specific symptoms. Patients with CFS and FM frequently reported symptoms compatible with MCS. Likewise, 70% of patients with FM and 30% of those with MCS met the criteria for CFS. Health care use was substantial among patients with CFS, FM, and MCS, with an average of 22.1, 39.7, and 23.3 visits, respectively, to a medical provider during the prior year. Health locus of control did not differ among the three populations.

CONCLUSIONS: In general, demographic and clinical factors and health locus of control do not clearly distinguish patients with CFS, FM, and MCS. Symptoms typical of each disorder are prevalent in the other two conditions.

Comment in: Chronic fatigue, fibromyalgia, and chemical sensitivity: overlapping disorders. [Arch Intern Med. 1995]

 

Source: Buchwald D, Garrity D. Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities. Arch Intern Med. 1994 Sep 26;154(18):2049-53. http://www.ncbi.nlm.nih.gov/pubmed/8092909