[Do we need polysomnography in insomnia?]. / Brauchen wir die Polysomnographie bei Insomnien?

The elimination of insurance coverage for polysomnography (PSG) in insomnia raised the question about the diagnostic value of this sole objective assessment of sleep. The methodology of PSG is described including the significant criteria for evaluating the recuperative value of sleep. Comparing clinical symptomatology and PSG shows, that the dominating symptoms are neither consistent nor specific, that the subjective evaluation of sleep by the patient is uncertain, and that extreme deviations may occur, especially in sleep state misperception. In the field of differential diagnosis, overlapping of insomnia with other disturbances within and outside the range of sleep medicine is frequent. Special problems arise in chronic non-organic pain. It is clear from all these aspects that PSG is indispensable in insomnia.

Insomnia and alpha sleep in chronic non-organic pain as compared to primary insomnia.

A considerable proportion of chronic non-organic pain patients suffer from insomnia, and alpha sleep has been suggested to be specifically associated with fibromyalgia. However, the clinical significance of those symptoms is not clear. This study was carried out to investigate this question. Twenty-six middle-aged, non-organic pain patients complaining of persistent insomnia were compared with 25 chronic primary insomniacs in a polysomnographic investigation. Alpha sleep was measured by automatic EEG analysis. A postsleep inventory allowed a separation of those pain patients with actual pain in the recording night to examine its possible influence on sleep. Both groups of patients displayed severe disturbance of sleep maintenance. The pain group did not differ in any of the insomnia variables or in sleep stages from chronic primary insomniacs. The occurrence of alpha sleep was high in either group which suggests that this is not a phenomenon specifically related to pain syndromes. A comparison of the pain subgroups revealed no difference between those with or without actual pain in the recording night. It is concluded that insomnia in chronic pain is of the same type and degree as primary insomnia. Apparently, the chronic process made insomnia so persistent that there was no response to actual night-time pain. Our study suggests that the interpretation of insomnia as secondary to pain, as it is usually made by the pain patients themselves, is a misattribution. It is suggested that insomnia in chronic pain patients should be taken seriously and treated by its specific methods.

Sleep, its subjective perception, and daytime performance in insomniacs with a pattern of alpha sleep.

Intrusion of alpha activity, an electroencephalographic (EEG) pattern typical for wakefulness, into sleep stages has repeatedly been described and investigated in various populations. Some studies suggested that it is a less deep and restorative sleep, but others did not support this interpretation. The present study was carried out to collect ample data on neurophysiology and subjective experience of sleep and on daytime cognitive performance to clarify this point. A sample of 128 primary insomniacs was investigated with polysomnography (PSG) that was submitted to a computerized, automatic analysis of alpha activity during sleep. It yielded two groups of 64 Ss each with a normal, that is, nonalpha sleep EEG and with alpha-sleep, respectively. Contrasting the two groups for PSG showed that alpha sleep Ss had significantly more stage 4 and a (nonsignificant) tendency for more awakenings. Subjectively, they largely underestimated intermittent wake time and consequently overestimated sleep duration by 50 min. The performance test battery showed a difference in one test only, that is, a better short-term memory function by alpha sleep Ss. In conclusion, there was no result supporting the assumption that alpha sleep is less restorative, but a significant lack of perception of intermittent awakenings during night sleep by alpha sleep Ss was found. The authors propose an explanation and point to the implications this misperception might have for the clinician.

[Sleep disorders: strategies for managing conflict by insomnia patients]. / Schlafstörungen: Konfliktbewältigungsstrategien von Insomniepatienten.

The investigation compares 136 insomniacs with 102 healthy controls with respect to their coping strategies. Coping strategies are evaluated with the questionnaire FKBS. This questionnaire measures 5 different coping strategies: TAS--turning against subject; TAO--turning against object; REV--reversal; PRN--prinzipialisation; PRO projection. Insomniacs seem to react less aggressive than healthy controls. They also show less projections, i.e. they do not believe in a hostile intention of a situation or a counterpart. These differences could be shown on the level of behaviour as well as experience. With the personality traits of the FPI (Freiburger Persönlichkeitsinventar FPI-R) there are some significant correlations. Finally there exists also a correlation between the strategy TAS and the incidence and intensity of depressive symptoms (i.e. state-variabels).

[The differential diagnostic value of polysomnography]. / Der differentialdiagnostische Wert der Polysomnographie.

Polysomnography (PSG) is a standard procedure for investigating sleep functions including behavior. This technique is described. The diagnostic value of PSG is shown by statistical data from the literature and our own patient sample which includes 442 insomniacs. In one out of five patients, insomnia is related to a known somatic factor, i.e. periodic movements in sleep or sleep apnea, which can only be reliably identified by PSG. A more differentiated analysis shows that PSG yields important diagnostic information in 50 to 75% of insomniacs. Three cases are reported, showing that even patients without clinical indications for sleep disturbance can have deficient sleep functions. If they can be specifically addressed, this may be the turning point of the treatment. Therefore, a wide application of PSG is favored.

Influence of desglycinamide-(arg8) vasopressin on memory in healthy subjects.

In 12 healthy student volunteers the influence on memory, attention and mood of a single dose of 2 mg of the vasopressin analog, desglycinamide-(arg8) vasopressin (DGAVP), given by the nasal route was investigated. On day 1 all subjects received placebo (single-blind), 1 week later they were given either DGAVP or placebo (double-blind). Memory effects were measured with the Buschke restrictive reminding method. DGAVP significantly improved storage processes, with retrieval processes less affected. Attention and mood processes were not influenced. It is suggested that DGAVP has an influence on memory processes.

Why low-dose benzodiazepine-dependent insomniacs can't escape their sleeping pills.

Psychobiological aspects of low-dose benzodiazepine dependence (LBD) and drug withdrawal were investigated in 76 middle-aged and elderly chronic insomniacs in a sleep laboratory. Comparison with drug-free insomniacs showed that LBD leads to a complete loss of hypnotic activity and substantial suppression of delta and REM sleep. Only small differences were found between benzodiazepines with different half-life time. Upon withdrawal, recovery from this suppression, especially in REM sleep, occurred, while insomnia did not increase. The patients, however, reported sleeping longer while taking the drug compared with withdrawal. This misperception seems to be a specific effect of benzodiazepines, and contrasts with the full awareness of insomnia upon withdrawal. It is concluded that these effects play a leading role in the patients' inability to escape their sleeping pills. The response of REM sleep to withdrawal should make this a useful measure to objectively confirm low-dose benzodiazepine dependence.

Twenty-four-hour sleep-wake function and personality patterns in chronic insomniacs and healthy controls.

A comparison was made between 16 middle-aged chronic insomniacs and 16 normal sleepers, matched by age and sex, in a psychophysiological study, including polysomnographic night sleep recordings, MMPI personality profiles, testing of cognitive performance, and relaxation capability during daytime. Both objective and subjective criteria of night sleep demonstrated a clear separation of the two groups. Insomniacs had psychosomatic personality profiles. A test for unintentional sleep suggested that poor sleep function in insomniacs is related to deficient sleep-controlling mechanisms, rather than psychological trait and state factors. Only sleep onset difficulties were susceptible to situational factors. Daytime performance was not generally impaired in insomniacs, but they had greater difficulties in the morning. Subjective daytime sleepiness was significantly higher and might represent a particular psychological problem for active behavior. Interrelations of various deficiencies in sleep-wake behavior seem to delineate specific aspects of the chronic insomniac syndrome.

[The use of DSIP (delta sleep-inducing peptide) in the correction of phase-shifted insomnia]. / Korrektur einer Insomnie mit Phasenverschiebung durch DSIP.

A 47-year old woman patient suffering from chronic delayed sleep phase insomnia and low-dose benzodiazepine dependence was treated as an inpatient under close polygraphic control using DSIP (delta sleep inducing peptide) on an intensive-care basis for one week. This treatment resulted in advancing the main sleep phase by 5 hours, in an abrupt and complete withdrawal of flunitrazepam and restitution of a normal sleep profile. Actographic control during an after treatment week confirmed that the success was maintained.

Effects of delta-sleep-inducing peptide on 24-hour sleep-wake behaviour in severe chronic insomnia.

Impaired daytime functions are a significant part of chronic insomnia besides sleep disturbance. Therefore, the effects of intermediate-term delta-sleep-inducing peptide (DSIP) administration on sleep and daytime performance were investigated in 14 middle-aged chronic insomniacs. DSIP was administered under placebo-controlled, double-blind conditions for 7 successive nights. Polysomnograms were obtained for placebo baseline, beginning and end of DSIP treatment, and one placebo posttreatment night; daytime psychological state and mental performance were extensively tested before and after 6 DSIP injections. The treatment substantially improved night sleep with the first and additionally with repeated doses. These effects were maintained for the first posttreatment (placebo) night. Efficiency of night sleep and daytime rest reached the levels of normal controls. Alertness and performance at daytime increased significantly. The study demonstrates the efficacy of DSIP for the treatment of impaired sleep and daytime functions as well.

Efficacy of DSIP to normalize sleep in middle-aged and elderly chronic insomniacs.

The immediate effects of one week of Delta Sleep-Inducing Peptide (DSIP) administration (6 X 30 nmol/kg b.w., i.v.) and late effects after a follow-up period of one week were investigated in a sleep laboratory study. The population of 18 chronic psychophysiological insomniacs was subdivided into two groups of middle-aged (29-59) and older (60-83) insomniacs. In the middle-aged insomniacs, improvement of sleep to normal values occurred by the end of DSIP administration and was maintained during the follow-up week. In the elderly insomniacs, who showed an initial sleep disturbance double as severe as the middle-aged group, the immediate effect was larger, but full normalization of sleep was only obtained by the end of the follow-up period. Although there was an interaction of sleep pathology and age, a regression analysis yielded clear evidence that the effects of DSIP were correlated to the degree of sleep disturbance. The whole sample of insomniacs showed normal sleep patterns at the end of the investigation.

DSIP in sleep disturbances.

The effects of DSIP on night sleep and on waking functions are demonstrated in double-blind studies in insomniacs, presenting influences of single dose treatments as well as of repeated injections. Moreover, a single case study describes the efficiency of DSIP on narcolepsy.

Evaluation of L-tryptophan for treatment of insomnia: a review.

Sleep laboratory and outpatient studies of the hypnotic efficacy of the amino acid L-tryptophan are reviewed, with particular emphasis on evaluation of therapeutic effectiveness in the treatment of insomnia. In younger situational insomniacs, whose sleep problem consists solely of longer than usual sleep latencies, L-tryptophan is effective in reducing sleep onset time on the first night of administration in doses ranging from 1 to 15 g. In more chronic, well-established sleep-onset insomnia or in more severe insomnias characterized by both sleep onset and sleep maintenance problems, repeated administration of low doses of L-tryptophan over time may be required for therapeutic improvement. In these patients, hypnotic effects appear late in the treatment period or, as shown in some studies, even after discontinuation of treatment. The improvement in sleep measures post-treatment has given rise to use of a treatment regimen known as "interval therapy", in which L-tryptophan treatment alternates with an L-tryptophan-free interval until improvement occurs. The absence of side effects and lack of development of tolerance in long-term use are important factors in the decision to embark upon a trial of L-tryptophan treatment. In addition, L-tryptophan administration is not associated with impairment of visuomotor, cognitive, or memory performance, nor does it elevate threshold for arousal from sleep.