Tag: sleep

Decreased tryptophan availability but normal post-synaptic 5-HT2c receptor sensitivity in chronic fatigue syndrome

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS) has been associated with increased prolactin (PRL) responses to the serotonin (5-HT) releasing agent fenfluramine. It is not known whether this abnormality is due to increased 5-HT release or heightened sensitivity of post-synaptic 5-HT receptors.

METHODS: We measured the increase in plasma PRL produced by the directly acting 5-HT receptor agonist, m-chlorophenylpiperazine (mCPP), in patients with CFS and healthy controls. We also compared the ability of mCPP to lower slow wave sleep (SWS) in the sleep polysomnogram of both subject groups. Finally, we measured plasma amino-acid levels to determine whether tryptophan availability differed between CFS subjects and controls.

RESULTS: mCPP elevated plasma PRL equivalently in patients with CFS and controls. Similarly, the decrease in SWS produced by mCPP did not differ between the two subject groups. Plasma-free tryptophan was significantly decreased in CFS.

CONCLUSIONS: The sensitivity of post-synaptic 5-HT2c receptors is not increased in patients with CFS. This suggests that the increased PRL response to fenfluramine in CFS is due to elevated activity of pre-synaptic 5-HT neurones. This change is unlikely to be due to increased peripheral availability of tryptophan.

 

Source: Vassallo CM, Feldman E, Peto T, Castell L, Sharpley AL, Cowen PJ. Decreased tryptophan availability but normal post-synaptic 5-HT2c receptor sensitivity in chronic fatigue syndrome. Psychol Med. 2001 May;31(4):585-91. http://www.ncbi.nlm.nih.gov/pubmed/11352361

 

Sleep and circadian rhythm disorders in fibromyalgia

Abstract:

Fibromyalgia (FM) is a syndrome of generalized muscle pain that is also associated with equally distressing symptoms of sleep disturbance and fatigue. FM shows clinical overlap with other stress-associated disorders, including chronic fatigue syndrome (CFS) and depression. All of these conditions have the features of disrupted sleep patterns and dysregulated biologic circadian rhythms, such as stress hormone secretion. This review focuses on the role of sleep and circadian rhythm disorders in FM and, in the absence of any specific treatment for FM, presents a pragmatic therapeutic approach aimed at identifying and treating comorbid sleep and depressive disorders, optimizing sleep habits, and judicious use of pharmacologic agents.

 

Source: Korszun A. Sleep and circadian rhythm disorders in fibromyalgia. Curr Rheumatol Rep. 2000 Apr;2(2):124-30. http://www.ncbi.nlm.nih.gov/pubmed/11123049

 

Nighttime sleep and daytime functioning (sleepiness and fatigue) in less well-defined chronic rheumatic diseases with particular reference to the ‘alpha-delta NREM sleep anomaly’

Abstract:

For the past 25 years, the ‘alpha-delta NREM sleep abnormality’ has been used by some as a defining or legitimizing marker for poorly defined rheumatic diseases such as fibromyalgia and chronic fatigue syndrome. Comprehensive review of the literature reveals no support for such a conclusion. Most studies involve small numbers of patients. The lack of control subjects, non-standardized recording techniques, and confusion between tonic and phasic alpha frequency activity patterns make comparison difficult.

There is much evidence that this sleep EEG pattern is not only non-specific, but may actually reflect a sleep maintaining process. The ‘sleep fragmentation’ theory of the complaint of non-restorative sleep in this patient population is invalidated by the fact that conditions characterized by severe sleep fragmentation, such as obstructive sleep apnea, are not associated with musculoskeletal symtoms. It is difficult to attribute musculoskeletal symptoms to disorders of sleep in view of the fact that the only organ of the body known to benefit from sleep, or to be adversely affected by lack of sleep, is the brain. It is concluded that fibromyalgia and chronic fatigue syndrome are associated with subjective sleep complaints, but do not represent sleep disorders.

 

Source: Mahowald ML, Mahowald MW. Nighttime sleep and daytime functioning (sleepiness and fatigue) in less well-defined chronic rheumatic diseases with particular reference to the ‘alpha-delta NREM sleep anomaly’. Sleep Med. 2000 Jul 1;1(3):195-207. http://www.ncbi.nlm.nih.gov/pubmed/10828430

 

Prognostic factors for persons with idiopathic chronic fatigue

Abstract:

BACKGROUND: The simultaneous examination of a large number of patient characteristics in a prospective study of patients with chronic fatigue.

OBJECTIVE: To compare the relative importance of these characteristics as prognostic factors.

METHODS: The data analyzed were from 199 subjects in a registry of persons who were aged 18 years or older and had idiopathic fatigue for at least 6 months. All subjects completed an extensive baseline questionnaire that provided information about fatigue, demographic characteristics, medical conditions, lifestyle, sleeping habits, psychological characteristics, and the presence of criteria for chronic fatigue syndrome. Changes in fatigue severity from baseline to 2-year follow-up were tested for an association with risk factors at baseline and with changes in symptoms other than fatigue during the follow-up period.

RESULTS: The following characteristics at baseline significantly and independently predicted greater fatigue improvement: less unclear thinking, fewer somatoform symptoms not used to define chronic fatigue syndrome, infrequent awakening, fewer hours sleeping, and being married. Of 29 subjects who at baseline reported no somatoform symptoms unrelated to chronic fatigue syndrome and who thought clearly most of the time, 8 substantially improved, compared with 1 of 29 subjects who had more than 2 somatoform symptoms and never thought clearly (P = .01). Improvements in the following symptoms were significantly and independently associated with improvements in fatigue: unclear thinking, depression, muscle aches, and trouble falling asleep.

CONCLUSIONS: This study identified characteristics of subjects that seem to be of prognostic importance for idiopathic chronic fatigue. Symptoms that change concomitantly with changes in fatigue may be intrinsically linked to fatigue.

 

Source: Hartz AJ, Kuhn EM, Bentler SE, Levine PH, London R. Prognostic factors for persons with idiopathic chronic fatigue. Arch Fam Med. 1999 Nov-Dec;8(6):495-501. http://www.ncbi.nlm.nih.gov/pubmed/10575388

 

A 56-Year-Old Woman With Chronic Fatigue Syndrome, 1 Year Later

In June 1997, at the Medicine Grand Rounds, Dr Anthony Komaroff discussed Ms H, an educator unable to work because of debilitating symptoms associated with a 2-year history of chronic fatigue. Her ailment, which began shortly after a flu-like illness, was marked primarily by weakness, fatigue, chronic insomnia, and depression that she felt was in response to her symptoms. In recent years she had felt somewhat less depressed, and wondered also if the disease might be slowly diminishing in its severity.

You can read the rest of this article here: http://jama.jamanetwork.com/article.aspx?articleid=187800

 

Source: Thomas L. Delbanco, MD; Jennifer Daley, MD; Erin E. Hartman, MS. A 56-Year-Old Woman With Chronic Fatigue Syndrome, 1 Year Later. JAMA. 1998;280(4):372. doi:10.1001/jama.280.4.372. http://jama.jamanetwork.com/article.aspx?articleid=187800

Depression and short REM latency in subjects with chronic fatigue syndrome

Abstract:

OBJECTIVE: The hypothesized polysomnographic marker for depression, Rapid Eye Movement Latency (REML), was used to investigate two groups of subjects; Chronic Fatigue Syndrome (CFS)-not depressed and CFS-depressed.

METHOD: CFS subjects were classified into depressed and not depressed groups, using the Diagnostic Interview Schedule (DIS), and subsequently were studied in a sleep laboratory to ascertain REML.

RESULTS: Short REML showed a statistically significant correlation with the depressed state in CFS subjects.

CONCLUSION: Short REM latency is associated with depression in the CFS population.

 

Source: Morehouse RL, Flanigan M, MacDonald DD, Braha D, Shapiro C. Depression and short REM latency in subjects with chronic fatigue syndrome. Psychosom Med. 1998 May-Jun;60(3):347-51. http://www.ncbi.nlm.nih.gov/pubmed/9625223

 

The relation of sleep difficulties to fatigue, mood and disability in chronic fatigue syndrome

Abstract:

The relationship of sleep complaints to mood, fatigue, disability, and lifestyle was examined in 69 chronic fatigue syndrome (CFS) patients without psychiatric disorder, 58 CFS patients with psychiatric disorder, 38 psychiatric out-patients with chronic depressive disorders, and 45 healthy controls. The groups were matched for age and gender.

There were few differences between the prevalence or nature of sleep complaints of CFS patients with or without current DSM-IIIR depression, anxiety or somatization disorder. CFS patients reported significantly more naps and waking by pain, a similar prevalence of difficulties in maintaining sleep, and significantly less difficulty getting off to sleep compared to depressed patients.

Sleep continuity complaints preceded fatigue in only 20% of CFS patients, but there was a strong association between relapse and sleep disturbance. Certain types of sleep disorder were associated with increased disability or fatigue in CFS patients. Disrupted sleep appears to complicate the course of CFS. For the most part, sleep complaints are either attributable to the lifestyle of CFS patients or seem inherent to the underlying condition of CFS. They are generally unrelated to depression or anxiety in CFS.

 

Source: Morriss RK, Wearden AJ, Battersby L. The relation of sleep difficulties to fatigue, mood and disability in chronic fatigue syndrome. J Psychosom Res. 1997 Jun;42(6):597-605. http://www.ncbi.nlm.nih.gov/pubmed/9226607

 

Dissociation of body-temperature and melatonin secretion circadian rhythms in patients with chronic fatigue syndrome

Abstract:

Many patients with chronic fatigue syndrome (CFS) display features of hypothalamic dysfunction. We have investigated aspects of circadian rhythmicity, an important hypothalamic function, in 20 CFS patients and in 17 age- and sex-matched healthy control subjects.

There were no differences between the two groups in the amplitude, mesor (mean value) or timing of the peak (acrophase) of the circadian rhythm of core temperature, or in the timing of the onset of melatonin secretion.

However, the CFS patients showed no significant correlation between the timing of the temperature acrophase and the melatonin onset (P < 0.5), whereas the normal significant correlation was observed in the controls (P < 0.05). Dissociation of circadian rhythms could be due to the sleep deprivation and social disruption, and/or the reduction in physical activity which typically accompany CFS.

By analogy with jet-lag and shift-working, circadian dysrhythmia could be an important factor in initiating and perpetuating the cardinal symptoms of CFS, notably tiredness, impaired concentration and intellectual impairment.

 

Source: Williams G, Pirmohamed J, Minors D, Waterhouse J, Buchan I, Arendt J, Edwards RH. Dissociation of body-temperature and melatonin secretion circadian rhythms in patients with chronic fatigue syndrome. Clin Physiol. 1996 Jul;16(4):327-37. http://www.ncbi.nlm.nih.gov/pubmed/8842569

 

Short-term night-shift working mimics the pituitary-adrenocortical dysfunction in chronic fatigue syndrome

Abstract:

The purpose of this study was to determine whether a short period (5 days) of night-shift work affected the pituitary-adrenal responses to CRH. Ten nurses (8 female and 2 male; age 28.1 +/- 1.7 yr: mean +/- SEM) working at the Royal Liverpool University Hospital, and who regularly undertook periods of night and day shift work were enrolled.

Measurements were made of basal ACTH and cortisol concentrations, and their responses to iv ovine CRH (1 microgram.kg-1). Basal ACTH concentrations were higher during the night shift than during the day shift (12.9 +/- 5.1 pmol.L-1 vs. 4.7 +/- 1.2 pmol.L-1, P < 0.01) whereas cortisol concentrations were lower (551 +/- 48 nmol.L – 1 vs. 871 +/- 132 nmol.L – 1, P < 0.01). After CRH injection, ACTH concentrations remained consistently higher during the night shift, but the integrated increase in ACTH concentration was lower (P < 0.05) than during the day shift. Conversely, the increase in cortisol concentration was greater during the night shift than the day shift (283 +/- 53 nmol.L-1 vs. 134 +/- 41 nmol.L-1, P < 0.05).

We conclude that the pituitary-adrenal responses to CRH are markedly disrupted after only 5 days of nighttime work. These abnormalities mimic those previously observed in patients with chronic fatigue syndrome. Neuroendocrine abnormalities reported to be characteristic of chronic fatigue syndrome may be merely the consequence of disrupted sleep and social routine.

 

Source: Leese G, Chattington P, Fraser W, Vora J, Edwards R, Williams G. Short-term night-shift working mimics the pituitary-adrenocortical dysfunction in chronic fatigue syndrome. J Clin Endocrinol Metab. 1996 May;81(5):1867-70. http://www.ncbi.nlm.nih.gov/pubmed/8626849

 

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