La malveille. Hypersomnie, somnolence, clinophilie

Excessive daytime sleepiness (EDS) is a very frequent symptom and can be considered as a semiotic interface between psychiatry, neurology, pneumology, endocrinology an internal medicine. Whenever a patient enters the psychiatrist office with an EDS complain, the practitioner has to cautiously evaluate the various conditions possibly responsible for this symptom and must integrate the treatment of EDS in his global therapeutic strategy. In both cases, the psychiatrist may find considerably helpful the intervention of a sleep medicine specialist. If clinical investigation is usually sufficient to diagnose the origin of EDS, polysomnography is mandatory to evaluate the severity of an obstructive sleep apnoea syndrome (OSAS) or a narcolepsy. Hypersomnia, frequently mixed up with sleepiness, is so common and its definition is so fuzzy that most of psychiatrists do not further investigate this aspect during the initial assessment. Some differences must be made between hypersomnia (increased sleep time >10 h per day), sleepiness (intermediate state between sleep and wakefulness, occurring usually during daytime), clinophily (the subject does not sleep even lying) and affective withdrawal (the subject is prostrated but can be very anxious or delusional). In the general population the frequency of hypersomnia varies between 0.5 and 8.7% depending on the definition. The best tool to evaluate hypersomnia is the sleep log: sleep time is self-recorded daily during one month. In the psychiatric field it is impossible to simply get rid of the somatic causes of EDS. In fact EDS can be secondary to a depression, but a real depression can commonly be the consequence of an OSAS even if the treatment of respiratory events is rarely sufficient to cure the depression. Moreover, OSAS can be associated to impotence, alcoholism, behaviour or memory disorders that are matters of concern for the psychiatrist. Narcolepsy and idiopathic hypersomnia are both associated to depression due to the decrease of the cognitive and social activities induced by the reduction of wakefulness during daytime. EDS is obviously a symptom of atypical and seasonal affective disorders (SAD). Atypical depression associates personality and mood disorders when SAD associates sadness, hypersomnia and bulimia (mainly for carbo-hydrates). Usually sleep polysomnography reveals less sleep than expected and the symptomatology is intermediary between hypersomnia and clinophily. Here clinophily is associated with an illusion of sleep called “agrypnagnosia”. Last but not least, most of the psychotropic drugs have sedative side effects, especially antidepressants and anxiolytics. The use, and abuse, of these drugs is a common cause of EDS and must be investigated systematically. If the “true” hypersomnia is relatively rare, a reduction of the daytime vigilance and an increase of the time spent in bed are common in psychiatry, although few studies have been specifically dedicated to this topic. These symptoms are frequently associated with resistant depression and decreased quality of life. Moreover, EDS can cause traffic accidents or occupational injuries and the psychiatrist engages his legal responsibility on this point.     

The phylogeny, ethology and nosology of yawning

Charles Darwin would have said that yawning was a useless piece of physiology. If so, then how should the survival of this very stereotyped behavior among the poikilothermal and homoeothermic vertebrates, from the basic brained reptiles to human primates, whether in the air, on the land or in the sea be understand? This issue of the ethnological, neurophysiologic and neuropsychological literature depicts yawning as being associated with an alternation of "awake-sleep" rhythms, sexuality, and nutrition, where it appears as a reference behavior of the mechanisms stimulating the state of vigilance. In pharmacology, yawning is used as an indicator of dopamine-ocytocinergic pathway activity, but in the Parkinson patient the neurologist sees it as an expression of therapeutic dopaminergic activity. J.M. Charcot and his school considered yawning as a clinical sign, long since forgotten. However, many patients complain about excessive yawning. Iatrogenic causes are the most frequent and can be found among many neurological diseases: vasovagal syncope, migraine, epilepsy, hypophyseal tumor, or stroke. Our ability to achieve motor and emotional behavior in resonance with others is deeply rooted in hominid evolution, and probably explains the strange phenomenon of contagious yawning.     

Corticocerebellar unit activity and ocular movements: saccadic-related changes during sleep and waking (author's transl)

Single unit activity of vermian oculomotor cortex (Lobules V, VI, VII) and conjugated horizontal rapid eye movements were recorded in the cat, during wakefulness (W) and paradoxical sleep (PS). Correlation between cerebellar and oculomotor events showed the following findings. During PS the units — mostly Purkinje (P) cells — all increased their rate of discharge (mossy fiber activation for P cells) in coincidence with saccadic movements. Two kinds of movement related cells were observed: (i) Most of the units showed an increase of their discharge rate together with occasional bursts. These events were related to magnitude and rate of the saccades without accurate synchronization. (ii) Some cells showed a burst type activation strictly synchronized with the rapid eye movements of sleep. During W, two thirds of the units changed their pattern of discharge (mossy fiber activation for P cells) with waking ocular activity. Modifications of discharge patterns were very different from cells to cells (activation or suppression, increase or decrease in the rate of discharge). Many cells had an accurately synchronized response with the saccades. Some units had a directional reactivity, others gave a similar response for opposite eye movements. P cells showed an increase of their climbing fiber driven activity during PS with eye movements compared with PS without saccades. During PS and W, complex spikes discharges of P cells evidently showed no accurate relation to saccadic eye movements. Functional significations of the above described events are also discussed.     

The effect of twelve weeks of tai chi exercises on sleep quality,pain perception,and death anxiety in elderly women

Physical activity has protective effects against mental illness, especially in the elderly. This study aimed to investigate the effects of 12 weeks of tai chi exercises on sleep quality, pain perception, and death anxiety in elderly women. The present study was semi-experimental, with a pretest-posttest design and a control group. The participants were 80 elderly women who were referred to the Health Center of Urmia University. Seventy subjects (35 in the control group and 15 in the experimental group) were selected purposefully and based on their accessibility. The experimental group practiced Tai Chi with 55–70% intensity for about12 weeks, three 60-minute sessions each week. Data gathered using three questionnaires including the Pittsburg Sleep Quality Index (PSQI), McGill Pain Perception Questionnaire, and Templer Death Anxiety Questionnaire (1970). SPSS software version 22 was employed to obtain the analysis of covariance of data. Results indicated that after 12 weeks of Tai Chi exercises, the sleep quality of the experimental group improved (P < 0.01) as opposed to that of the control group. Furthermore, the pain perception and death anxiety rate in the experimental group decreased (P < 0.01) compared to that of the control group. Finding revealed that performing Tai Chi exercises improved sleep quality, reduced pain perception, and protected elders from death anxiety as well.     

Troubles du sommeil : caractéristiques sociodémographiques et comorbidités anxiodépressives. Étude (Baromètre santé INPES) chez 14 734 adultes en France

Aim

Several studies have identified a high prevalence of sleep disorders and insomnia in the French population; however these studies especially focused on sleep did not give enough details on the sociodemographic and occupational characteristics of subjects with sleep disorders. The aim of this study was to characterize adults complaining of sleep disorders in a vast population-based health demographics study (Baromètre Santé, Institut national pour l’éducation à la santé [INPES]).

Method

Fourteen thousand seven hundred and thirty-four adults aged from 18 to 65 years old were interviewed by telephone and “subjects with severe sleep disorders in the last 8 days” were isolated and compared with the others regarding sociodemographic and occupational aspects and with regard to psychiatric disorders. The sleep items were extracted from the Duke and WHOQOL (brief form) questionnaires. Depressive disorders were recognized based on the Composite International Diagnostic Interview (CIDI) Short-Form (CIDI-SF) and the ISD 10.

Results

Among the subjects, 12.5% were concerned. Women, young or subjects after 45, low income, employees and unemployed categories had significantly more sleep disorders. Sleep disorders in the last 8 days were also significantly linked to previous depressive episodes, anxiety disorders and history of suicide.

Conclusion

Assessing sleep disorders in the last 8 days seems to be a good method to identify severely affected subjects in general population surveys.